ref-parser.js

/*!
 * JSON Schema $Ref Parser v6.1.0 (February 21st 2019)
 * 
 * https://apidevtools.org/json-schema-ref-parser/
 * 
 * @author  James Messinger (https://jamesmessinger.com)
 * @license MIT
 */
(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.$RefParser = f()}})(function(){var define,module,exports;return (function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
"use strict";

var $Ref = require("./ref"),
    Pointer = require("./pointer"),
    url = require("./util/url");

module.exports = bundle;

/**
 * Bundles all external JSON references into the main JSON schema, thus resulting in a schema that
 * only has *internal* references, not any *external* references.
 * This method mutates the JSON schema object, adding new references and re-mapping existing ones.
 *
 * @param {$RefParser} parser
 * @param {$RefParserOptions} options
 */
function bundle (parser, options) {
  // console.log('Bundling $ref pointers in %s', parser.$refs._root$Ref.path);

  // Build an inventory of all $ref pointers in the JSON Schema
  var inventory = [];
  crawl(parser, "schema", parser.$refs._root$Ref.path + "#", "#", 0, inventory, parser.$refs, options);

  // Remap all $ref pointers
  remap(inventory);
}

/**
 * Recursively crawls the given value, and inventories all JSON references.
 *
 * @param {object} parent - The object containing the value to crawl. If the value is not an object or array, it will be ignored.
 * @param {string} key - The property key of `parent` to be crawled
 * @param {string} path - The full path of the property being crawled, possibly with a JSON Pointer in the hash
 * @param {string} pathFromRoot - The path of the property being crawled, from the schema root
 * @param {object[]} inventory - An array of already-inventoried $ref pointers
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 */
function crawl (parent, key, path, pathFromRoot, indirections, inventory, $refs, options) {
  var obj = key === null ? parent : parent[key];

  if (obj && typeof obj === "object") {
    if ($Ref.isAllowed$Ref(obj)) {
      inventory$Ref(parent, key, path, pathFromRoot, indirections, inventory, $refs, options);
    }
    else {
      // Crawl the object in a specific order that's optimized for bundling.
      // This is important because it determines how `pathFromRoot` gets built,
      // which later determines which keys get dereferenced and which ones get remapped
      var keys = Object.keys(obj)
        .sort(function (a, b) {
          // Most people will expect references to be bundled into the the "definitions" property,
          // so we always crawl that property first, if it exists.
          if (a === "definitions") {
            return -1;
          }
          else if (b === "definitions") {
            return 1;
          }
          else {
            // Otherwise, crawl the keys based on their length.
            // This produces the shortest possible bundled references
            return a.length - b.length;
          }
        });

      keys.forEach(function (key) {
        var keyPath = Pointer.join(path, key);
        var keyPathFromRoot = Pointer.join(pathFromRoot, key);
        var value = obj[key];

        if ($Ref.isAllowed$Ref(value)) {
          inventory$Ref(obj, key, path, keyPathFromRoot, indirections, inventory, $refs, options);
        }
        else {
          crawl(obj, key, keyPath, keyPathFromRoot, indirections, inventory, $refs, options);
        }
      });
    }
  }
}

/**
 * Inventories the given JSON Reference (i.e. records detailed information about it so we can
 * optimize all $refs in the schema), and then crawls the resolved value.
 *
 * @param {object} $refParent - The object that contains a JSON Reference as one of its keys
 * @param {string} $refKey - The key in `$refParent` that is a JSON Reference
 * @param {string} path - The full path of the JSON Reference at `$refKey`, possibly with a JSON Pointer in the hash
 * @param {string} pathFromRoot - The path of the JSON Reference at `$refKey`, from the schema root
 * @param {object[]} inventory - An array of already-inventoried $ref pointers
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 */
function inventory$Ref ($refParent, $refKey, path, pathFromRoot, indirections, inventory, $refs, options) {
  var $ref = $refKey === null ? $refParent : $refParent[$refKey];
  var $refPath = url.resolve(path, $ref.$ref);
  var pointer = $refs._resolve($refPath, options);
  var depth = Pointer.parse(pathFromRoot).length;
  var file = url.stripHash(pointer.path);
  var hash = url.getHash(pointer.path);
  var external = file !== $refs._root$Ref.path;
  var extended = $Ref.isExtended$Ref($ref);
  indirections += pointer.indirections;

  var existingEntry = findInInventory(inventory, $refParent, $refKey);
  if (existingEntry) {
    // This $Ref has already been inventoried, so we don't need to process it again
    if (depth < existingEntry.depth || indirections < existingEntry.indirections) {
      removeFromInventory(inventory, existingEntry);
    }
    else {
      return;
    }
  }

  inventory.push({
    $ref: $ref,                   // The JSON Reference (e.g. {$ref: string})
    parent: $refParent,           // The object that contains this $ref pointer
    key: $refKey,                 // The key in `parent` that is the $ref pointer
    pathFromRoot: pathFromRoot,   // The path to the $ref pointer, from the JSON Schema root
    depth: depth,                 // How far from the JSON Schema root is this $ref pointer?
    file: file,                   // The file that the $ref pointer resolves to
    hash: hash,                   // The hash within `file` that the $ref pointer resolves to
    value: pointer.value,         // The resolved value of the $ref pointer
    circular: pointer.circular,   // Is this $ref pointer DIRECTLY circular? (i.e. it references itself)
    extended: extended,           // Does this $ref extend its resolved value? (i.e. it has extra properties, in addition to "$ref")
    external: external,           // Does this $ref pointer point to a file other than the main JSON Schema file?
    indirections: indirections,   // The number of indirect references that were traversed to resolve the value
  });

  // Recursively crawl the resolved value
  crawl(pointer.value, null, pointer.path, pathFromRoot, indirections + 1, inventory, $refs, options);
}

/**
 * Re-maps every $ref pointer, so that they're all relative to the root of the JSON Schema.
 * Each referenced value is dereferenced EXACTLY ONCE.  All subsequent references to the same
 * value are re-mapped to point to the first reference.
 *
 * @example:
 *  {
 *    first: { $ref: somefile.json#/some/part },
 *    second: { $ref: somefile.json#/another/part },
 *    third: { $ref: somefile.json },
 *    fourth: { $ref: somefile.json#/some/part/sub/part }
 *  }
 *
 * In this example, there are four references to the same file, but since the third reference points
 * to the ENTIRE file, that's the only one we need to dereference.  The other three can just be
 * remapped to point inside the third one.
 *
 * On the other hand, if the third reference DIDN'T exist, then the first and second would both need
 * to be dereferenced, since they point to different parts of the file. The fourth reference does NOT
 * need to be dereferenced, because it can be remapped to point inside the first one.
 *
 * @param {object[]} inventory
 */
function remap (inventory) {
  // Group & sort all the $ref pointers, so they're in the order that we need to dereference/remap them
  inventory.sort(function (a, b) {
    if (a.file !== b.file) {
      // Group all the $refs that point to the same file
      return a.file < b.file ? -1 : +1;
    }
    else if (a.hash !== b.hash) {
      // Group all the $refs that point to the same part of the file
      return a.hash < b.hash ? -1 : +1;
    }
    else if (a.circular !== b.circular) {
      // If the $ref points to itself, then sort it higher than other $refs that point to this $ref
      return a.circular ? -1 : +1;
    }
    else if (a.extended !== b.extended) {
      // If the $ref extends the resolved value, then sort it lower than other $refs that don't extend the value
      return a.extended ? +1 : -1;
    }
    else if (a.indirections !== b.indirections) {
      // Sort direct references higher than indirect references
      return a.indirections - b.indirections;
    }
    else if (a.depth !== b.depth) {
      // Sort $refs by how close they are to the JSON Schema root
      return a.depth - b.depth;
    }
    else {
      // Determine how far each $ref is from the "definitions" property.
      // Most people will expect references to be bundled into the the "definitions" property if possible.
      var aDefinitionsIndex = a.pathFromRoot.lastIndexOf("/definitions");
      var bDefinitionsIndex = b.pathFromRoot.lastIndexOf("/definitions");

      if (aDefinitionsIndex !== bDefinitionsIndex) {
        // Give higher priority to the $ref that's closer to the "definitions" property
        return bDefinitionsIndex - aDefinitionsIndex;
      }
      else {
        // All else is equal, so use the shorter path, which will produce the shortest possible reference
        return a.pathFromRoot.length - b.pathFromRoot.length;
      }
    }
  });

  var file, hash, pathFromRoot;
  inventory.forEach(function (entry) {
    // console.log('Re-mapping $ref pointer "%s" at %s', entry.$ref.$ref, entry.pathFromRoot);

    if (!entry.external) {
      // This $ref already resolves to the main JSON Schema file
      entry.$ref.$ref = entry.hash;
    }
    else if (entry.file === file && entry.hash === hash) {
      // This $ref points to the same value as the prevous $ref, so remap it to the same path
      entry.$ref.$ref = pathFromRoot;
    }
    else if (entry.file === file && entry.hash.indexOf(hash + "/") === 0) {
      // This $ref points to a sub-value of the prevous $ref, so remap it beneath that path
      entry.$ref.$ref = Pointer.join(pathFromRoot, Pointer.parse(entry.hash.replace(hash, "#")));
    }
    else {
      // We've moved to a new file or new hash
      file = entry.file;
      hash = entry.hash;
      pathFromRoot = entry.pathFromRoot;

      // This is the first $ref to point to this value, so dereference the value.
      // Any other $refs that point to the same value will point to this $ref instead
      entry.$ref = entry.parent[entry.key] = $Ref.dereference(entry.$ref, entry.value);

      if (entry.circular) {
        // This $ref points to itself
        entry.$ref.$ref = entry.pathFromRoot;
      }
    }

    // console.log('    new value: %s', (entry.$ref && entry.$ref.$ref) ? entry.$ref.$ref : '[object Object]');
  });
}

/**
 * TODO
 */
function findInInventory (inventory, $refParent, $refKey) {
  for (var i = 0; i < inventory.length; i++) {
    var existingEntry = inventory[i];
    if (existingEntry.parent === $refParent && existingEntry.key === $refKey) {
      return existingEntry;
    }
  }
}

function removeFromInventory (inventory, entry) {
  var index = inventory.indexOf(entry);
  inventory.splice(index, 1);
}

},{"./pointer":11,"./ref":12,"./util/url":18}],2:[function(require,module,exports){
"use strict";

var $Ref = require("./ref"),
    Pointer = require("./pointer"),
    ono = require("ono"),
    url = require("./util/url");

module.exports = dereference;

/**
 * Crawls the JSON schema, finds all JSON references, and dereferences them.
 * This method mutates the JSON schema object, replacing JSON references with their resolved value.
 *
 * @param {$RefParser} parser
 * @param {$RefParserOptions} options
 */
function dereference (parser, options) {
  // console.log('Dereferencing $ref pointers in %s', parser.$refs._root$Ref.path);
  var dereferenced = crawl(parser.schema, parser.$refs._root$Ref.path, "#", [], parser.$refs, options);
  parser.$refs.circular = dereferenced.circular;
  parser.schema = dereferenced.value;
}

/**
 * Recursively crawls the given value, and dereferences any JSON references.
 *
 * @param {*} obj - The value to crawl. If it's not an object or array, it will be ignored.
 * @param {string} path - The full path of `obj`, possibly with a JSON Pointer in the hash
 * @param {string} pathFromRoot - The path of `obj` from the schema root
 * @param {object[]} parents - An array of the parent objects that have already been dereferenced
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 * @returns {{value: object, circular: boolean}}
 */
function crawl (obj, path, pathFromRoot, parents, $refs, options) {
  var dereferenced;
  var result = {
    value: obj,
    circular: false
  };

  if (obj && typeof obj === "object") {
    parents.push(obj);

    if ($Ref.isAllowed$Ref(obj, options)) {
      dereferenced = dereference$Ref(obj, path, pathFromRoot, parents, $refs, options);
      result.circular = dereferenced.circular;
      result.value = dereferenced.value;
    }
    else {
      Object.keys(obj).forEach(function (key) {
        var keyPath = Pointer.join(path, key);
        var keyPathFromRoot = Pointer.join(pathFromRoot, key);
        var value = obj[key];
        var circular = false;

        if ($Ref.isAllowed$Ref(value, options)) {
          dereferenced = dereference$Ref(value, keyPath, keyPathFromRoot, parents, $refs, options);
          circular = dereferenced.circular;
          obj[key] = dereferenced.value;
        }
        else {
          if (parents.indexOf(value) === -1) {
            dereferenced = crawl(value, keyPath, keyPathFromRoot, parents, $refs, options);
            circular = dereferenced.circular;
            obj[key] = dereferenced.value;
          }
          else {
            circular = foundCircularReference(keyPath, $refs, options);
          }
        }

        // Set the "isCircular" flag if this or any other property is circular
        result.circular = result.circular || circular;
      });
    }

    parents.pop();
  }

  return result;
}

/**
 * Dereferences the given JSON Reference, and then crawls the resulting value.
 *
 * @param {{$ref: string}} $ref - The JSON Reference to resolve
 * @param {string} path - The full path of `$ref`, possibly with a JSON Pointer in the hash
 * @param {string} pathFromRoot - The path of `$ref` from the schema root
 * @param {object[]} parents - An array of the parent objects that have already been dereferenced
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 * @returns {{value: object, circular: boolean}}
 */
function dereference$Ref ($ref, path, pathFromRoot, parents, $refs, options) {
  // console.log('Dereferencing $ref pointer "%s" at %s', $ref.$ref, path);

  var $refPath = url.resolve(path, $ref.$ref);
  var pointer = $refs._resolve($refPath, options);

  // Check for circular references
  var directCircular = pointer.circular;
  var circular = directCircular || parents.indexOf(pointer.value) !== -1;
  circular && foundCircularReference(path, $refs, options);

  // Dereference the JSON reference
  var dereferencedValue = $Ref.dereference($ref, pointer.value);

  // Crawl the dereferenced value (unless it's circular)
  if (!circular) {
    // Determine if the dereferenced value is circular
    var dereferenced = crawl(dereferencedValue, pointer.path, pathFromRoot, parents, $refs, options);
    circular = dereferenced.circular;
    dereferencedValue = dereferenced.value;
  }

  if (circular && !directCircular && options.dereference.circular === "ignore") {
    // The user has chosen to "ignore" circular references, so don't change the value
    dereferencedValue = $ref;
  }

  if (directCircular) {
    // The pointer is a DIRECT circular reference (i.e. it references itself).
    // So replace the $ref path with the absolute path from the JSON Schema root
    dereferencedValue.$ref = pathFromRoot;
  }

  return {
    circular: circular,
    value: dereferencedValue
  };
}

/**
 * Called when a circular reference is found.
 * It sets the {@link $Refs#circular} flag, and throws an error if options.dereference.circular is false.
 *
 * @param {string} keyPath - The JSON Reference path of the circular reference
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 * @returns {boolean} - always returns true, to indicate that a circular reference was found
 */
function foundCircularReference (keyPath, $refs, options) {
  $refs.circular = true;
  if (!options.dereference.circular) {
    throw ono.reference("Circular $ref pointer found at %s", keyPath);
  }
  return true;
}

},{"./pointer":11,"./ref":12,"./util/url":18,"ono":64}],3:[function(require,module,exports){
(function (Buffer){
"use strict";

var Options = require("./options"),
    $Refs = require("./refs"),
    parse = require("./parse"),
    normalizeArgs = require("./normalize-args"),
    resolveExternal = require("./resolve-external"),
    bundle = require("./bundle"),
    dereference = require("./dereference"),
    url = require("./util/url"),
    maybe = require("call-me-maybe"),
    ono = require("ono");

module.exports = $RefParser;
module.exports.YAML = require("./util/yaml");

/**
 * This class parses a JSON schema, builds a map of its JSON references and their resolved values,
 * and provides methods for traversing, manipulating, and dereferencing those references.
 *
 * @constructor
 */
function $RefParser () {
  /**
   * The parsed (and possibly dereferenced) JSON schema object
   *
   * @type {object}
   * @readonly
   */
  this.schema = null;

  /**
   * The resolved JSON references
   *
   * @type {$Refs}
   * @readonly
   */
  this.$refs = new $Refs();
}

/**
 * Parses the given JSON schema.
 * This method does not resolve any JSON references.
 * It just reads a single file in JSON or YAML format, and parse it as a JavaScript object.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed
 * @param {function} [callback] - An error-first callback. The second parameter is the parsed JSON schema object.
 * @returns {Promise} - The returned promise resolves with the parsed JSON schema object.
 */
$RefParser.parse = function (path, schema, options, callback) {
  var Class = this; // eslint-disable-line consistent-this
  var instance = new Class();
  return instance.parse.apply(instance, arguments);
};

/**
 * Parses the given JSON schema.
 * This method does not resolve any JSON references.
 * It just reads a single file in JSON or YAML format, and parse it as a JavaScript object.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed
 * @param {function} [callback] - An error-first callback. The second parameter is the parsed JSON schema object.
 * @returns {Promise} - The returned promise resolves with the parsed JSON schema object.
 */
$RefParser.prototype.parse = function (path, schema, options, callback) {
  var args = normalizeArgs(arguments);
  var promise;

  if (!args.path && !args.schema) {
    var err = ono("Expected a file path, URL, or object. Got %s", args.path || args.schema);
    return maybe(args.callback, Promise.reject(err));
  }

  // Reset everything
  this.schema = null;
  this.$refs = new $Refs();

  // If the path is a filesystem path, then convert it to a URL.
  // NOTE: According to the JSON Reference spec, these should already be URLs,
  // but, in practice, many people use local filesystem paths instead.
  // So we're being generous here and doing the conversion automatically.
  // This is not intended to be a 100% bulletproof solution.
  // If it doesn't work for your use-case, then use a URL instead.
  var pathType = "http";
  if (url.isFileSystemPath(args.path)) {
    args.path = url.fromFileSystemPath(args.path);
    pathType = "file";
  }

  // Resolve the absolute path of the schema
  args.path = url.resolve(url.cwd(), args.path);

  if (args.schema && typeof args.schema === "object") {
    // A schema object was passed-in.
    // So immediately add a new $Ref with the schema object as its value
    var $ref = this.$refs._add(args.path);
    $ref.value = args.schema;
    $ref.pathType = pathType;
    promise = Promise.resolve(args.schema);
  }
  else {
    // Parse the schema file/url
    promise = parse(args.path, this.$refs, args.options);
  }

  var me = this;
  return promise
    .then(function (result) {
      if (!result || typeof result !== "object" || Buffer.isBuffer(result)) {
        throw ono.syntax('"%s" is not a valid JSON Schema', me.$refs._root$Ref.path || result);
      }
      else {
        me.schema = result;
        return maybe(args.callback, Promise.resolve(me.schema));
      }
    })
    .catch(function (e) {
      return maybe(args.callback, Promise.reject(e));
    });
};

/**
 * Parses the given JSON schema and resolves any JSON references, including references in
 * externally-referenced files.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed and resolved
 * @param {function} [callback]
 * - An error-first callback. The second parameter is a {@link $Refs} object containing the resolved JSON references
 *
 * @returns {Promise}
 * The returned promise resolves with a {@link $Refs} object containing the resolved JSON references
 */
$RefParser.resolve = function (path, schema, options, callback) {
  var Class = this; // eslint-disable-line consistent-this
  var instance = new Class();
  return instance.resolve.apply(instance, arguments);
};

/**
 * Parses the given JSON schema and resolves any JSON references, including references in
 * externally-referenced files.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed and resolved
 * @param {function} [callback]
 * - An error-first callback. The second parameter is a {@link $Refs} object containing the resolved JSON references
 *
 * @returns {Promise}
 * The returned promise resolves with a {@link $Refs} object containing the resolved JSON references
 */
$RefParser.prototype.resolve = function (path, schema, options, callback) {
  var me = this;
  var args = normalizeArgs(arguments);

  return this.parse(args.path, args.schema, args.options)
    .then(function () {
      return resolveExternal(me, args.options);
    })
    .then(function () {
      return maybe(args.callback, Promise.resolve(me.$refs));
    })
    .catch(function (err) {
      return maybe(args.callback, Promise.reject(err));
    });
};

/**
 * Parses the given JSON schema, resolves any JSON references, and bundles all external references
 * into the main JSON schema. This produces a JSON schema that only has *internal* references,
 * not any *external* references.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed, resolved, and dereferenced
 * @param {function} [callback] - An error-first callback. The second parameter is the bundled JSON schema object
 * @returns {Promise} - The returned promise resolves with the bundled JSON schema object.
 */
$RefParser.bundle = function (path, schema, options, callback) {
  var Class = this; // eslint-disable-line consistent-this
  var instance = new Class();
  return instance.bundle.apply(instance, arguments);
};

/**
 * Parses the given JSON schema, resolves any JSON references, and bundles all external references
 * into the main JSON schema. This produces a JSON schema that only has *internal* references,
 * not any *external* references.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed, resolved, and dereferenced
 * @param {function} [callback] - An error-first callback. The second parameter is the bundled JSON schema object
 * @returns {Promise} - The returned promise resolves with the bundled JSON schema object.
 */
$RefParser.prototype.bundle = function (path, schema, options, callback) {
  var me = this;
  var args = normalizeArgs(arguments);

  return this.resolve(args.path, args.schema, args.options)
    .then(function () {
      bundle(me, args.options);
      return maybe(args.callback, Promise.resolve(me.schema));
    })
    .catch(function (err) {
      return maybe(args.callback, Promise.reject(err));
    });
};

/**
 * Parses the given JSON schema, resolves any JSON references, and dereferences the JSON schema.
 * That is, all JSON references are replaced with their resolved values.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed, resolved, and dereferenced
 * @param {function} [callback] - An error-first callback. The second parameter is the dereferenced JSON schema object
 * @returns {Promise} - The returned promise resolves with the dereferenced JSON schema object.
 */
$RefParser.dereference = function (path, schema, options, callback) {
  var Class = this; // eslint-disable-line consistent-this
  var instance = new Class();
  return instance.dereference.apply(instance, arguments);
};

/**
 * Parses the given JSON schema, resolves any JSON references, and dereferences the JSON schema.
 * That is, all JSON references are replaced with their resolved values.
 *
 * @param {string} [path] - The file path or URL of the JSON schema
 * @param {object} [schema] - A JSON schema object. This object will be used instead of reading from `path`.
 * @param {$RefParserOptions} [options] - Options that determine how the schema is parsed, resolved, and dereferenced
 * @param {function} [callback] - An error-first callback. The second parameter is the dereferenced JSON schema object
 * @returns {Promise} - The returned promise resolves with the dereferenced JSON schema object.
 */
$RefParser.prototype.dereference = function (path, schema, options, callback) {
  var me = this;
  var args = normalizeArgs(arguments);

  return this.resolve(args.path, args.schema, args.options)
    .then(function () {
      dereference(me, args.options);
      return maybe(args.callback, Promise.resolve(me.schema));
    })
    .catch(function (err) {
      return maybe(args.callback, Promise.reject(err));
    });
};

}).call(this,{"isBuffer":require("../node_modules/is-buffer/index.js")})

},{"../node_modules/is-buffer/index.js":32,"./bundle":1,"./dereference":2,"./normalize-args":4,"./options":5,"./parse":6,"./refs":13,"./resolve-external":14,"./util/url":18,"./util/yaml":19,"call-me-maybe":25,"ono":64}],4:[function(require,module,exports){
"use strict";

var Options = require("./options");

module.exports = normalizeArgs;

/**
 * Normalizes the given arguments, accounting for optional args.
 *
 * @param {Arguments} args
 * @returns {object}
 */
function normalizeArgs (args) {
  var path, schema, options, callback;
  args = Array.prototype.slice.call(args);

  if (typeof args[args.length - 1] === "function") {
    // The last parameter is a callback function
    callback = args.pop();
  }

  if (typeof args[0] === "string") {
    // The first parameter is the path
    path = args[0];
    if (typeof args[2] === "object") {
      // The second parameter is the schema, and the third parameter is the options
      schema = args[1];
      options = args[2];
    }
    else {
      // The second parameter is the options
      schema = undefined;
      options = args[1];
    }
  }
  else {
    // The first parameter is the schema
    path = "";
    schema = args[0];
    options = args[1];
  }

  if (!(options instanceof Options)) {
    options = new Options(options);
  }

  return {
    path: path,
    schema: schema,
    options: options,
    callback: callback
  };
}

},{"./options":5}],5:[function(require,module,exports){
/* eslint lines-around-comment: [2, {beforeBlockComment: false}] */
"use strict";

var jsonParser = require("./parsers/json"),
    yamlParser = require("./parsers/yaml"),
    textParser = require("./parsers/text"),
    binaryParser = require("./parsers/binary"),
    fileResolver = require("./resolvers/file"),
    httpResolver = require("./resolvers/http");

module.exports = $RefParserOptions;

/**
 * Options that determine how JSON schemas are parsed, resolved, and dereferenced.
 *
 * @param {object|$RefParserOptions} [options] - Overridden options
 * @constructor
 */
function $RefParserOptions (options) {
  merge(this, $RefParserOptions.defaults);
  merge(this, options);
}

$RefParserOptions.defaults = {
  /**
   * Determines how different types of files will be parsed.
   *
   * You can add additional parsers of your own, replace an existing one with
   * your own implemenation, or disable any parser by setting it to false.
   */
  parse: {
    json: jsonParser,
    yaml: yamlParser,
    text: textParser,
    binary: binaryParser,
  },

  /**
   * Determines how JSON References will be resolved.
   *
   * You can add additional resolvers of your own, replace an existing one with
   * your own implemenation, or disable any resolver by setting it to false.
   */
  resolve: {
    file: fileResolver,
    http: httpResolver,

    /**
     * Determines whether external $ref pointers will be resolved.
     * If this option is disabled, then none of above resolvers will be called.
     * Instead, external $ref pointers will simply be ignored.
     *
     * @type {boolean}
     */
    external: true,
  },

  /**
   * Determines the types of JSON references that are allowed.
   */
  dereference: {
    /**
     * Dereference circular (recursive) JSON references?
     * If false, then a {@link ReferenceError} will be thrown if a circular reference is found.
     * If "ignore", then circular references will not be dereferenced.
     *
     * @type {boolean|string}
     */
    circular: true
  },
};

/**
 * Merges the properties of the source object into the target object.
 *
 * @param {object} target - The object that we're populating
 * @param {?object} source - The options that are being merged
 * @returns {object}
 */
function merge (target, source) {
  if (isMergeable(source)) {
    var keys = Object.keys(source);
    for (var i = 0; i < keys.length; i++) {
      var key = keys[i];
      var sourceSetting = source[key];
      var targetSetting = target[key];

      if (isMergeable(sourceSetting)) {
        // It's a nested object, so merge it recursively
        target[key] = merge(targetSetting || {}, sourceSetting);
      }
      else if (sourceSetting !== undefined) {
        // It's a scalar value, function, or array. No merging necessary. Just overwrite the target value.
        target[key] = sourceSetting;
      }
    }
  }
  return target;
}

/**
 * Determines whether the given value can be merged,
 * or if it is a scalar value that should just override the target value.
 *
 * @param   {*}  val
 * @returns {Boolean}
 */
function isMergeable (val) {
  return val &&
    (typeof val === "object") &&
    !Array.isArray(val) &&
    !(val instanceof RegExp) &&
    !(val instanceof Date);
}

},{"./parsers/binary":7,"./parsers/json":8,"./parsers/text":9,"./parsers/yaml":10,"./resolvers/file":15,"./resolvers/http":16}],6:[function(require,module,exports){
(function (Buffer){
"use strict";

var ono = require("ono"),
    url = require("./util/url"),
    plugins = require("./util/plugins");

module.exports = parse;

/**
 * Reads and parses the specified file path or URL.
 *
 * @param {string} path - This path MUST already be resolved, since `read` doesn't know the resolution context
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 *
 * @returns {Promise}
 * The promise resolves with the parsed file contents, NOT the raw (Buffer) contents.
 */
function parse (path, $refs, options) {
  try {
    // Remove the URL fragment, if any
    path = url.stripHash(path);

    // Add a new $Ref for this file, even though we don't have the value yet.
    // This ensures that we don't simultaneously read & parse the same file multiple times
    var $ref = $refs._add(path);

    // This "file object" will be passed to all resolvers and parsers.
    var file = {
      url: path,
      extension: url.getExtension(path),
    };

    // Read the file and then parse the data
    return readFile(file, options)
      .then(function (resolver) {
        $ref.pathType = resolver.plugin.name;
        file.data = resolver.result;
        return parseFile(file, options);
      })
      .then(function (parser) {
        $ref.value = parser.result;
        return parser.result;
      });
  }
  catch (e) {
    return Promise.reject(e);
  }
}

/**
 * Reads the given file, using the configured resolver plugins
 *
 * @param {object} file           - An object containing information about the referenced file
 * @param {string} file.url       - The full URL of the referenced file
 * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
 * @param {$RefParserOptions} options
 *
 * @returns {Promise}
 * The promise resolves with the raw file contents and the resolver that was used.
 */
function readFile (file, options) {
  return new Promise(function (resolve, reject) {
    // console.log('Reading %s', file.url);

    // Find the resolvers that can read this file
    var resolvers = plugins.all(options.resolve);
    resolvers = plugins.filter(resolvers, "canRead", file);

    // Run the resolvers, in order, until one of them succeeds
    plugins.sort(resolvers);
    plugins.run(resolvers, "read", file)
      .then(resolve, onError);

    function onError (err) {
      // Throw the original error, if it's one of our own (user-friendly) errors.
      // Otherwise, throw a generic, friendly error.
      if (err && !(err instanceof SyntaxError)) {
        reject(err);
      }
      else {
        reject(ono.syntax('Unable to resolve $ref pointer "%s"', file.url));
      }
    }
  });
}

/**
 * Parses the given file's contents, using the configured parser plugins.
 *
 * @param {object} file           - An object containing information about the referenced file
 * @param {string} file.url       - The full URL of the referenced file
 * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
 * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
 * @param {$RefParserOptions} options
 *
 * @returns {Promise}
 * The promise resolves with the parsed file contents and the parser that was used.
 */
function parseFile (file, options) {
  return new Promise(function (resolve, reject) {
    // console.log('Parsing %s', file.url);

    // Find the parsers that can read this file type.
    // If none of the parsers are an exact match for this file, then we'll try ALL of them.
    // This handles situations where the file IS a supported type, just with an unknown extension.
    var allParsers = plugins.all(options.parse);
    var filteredParsers = plugins.filter(allParsers, "canParse", file);
    var parsers = filteredParsers.length > 0 ? filteredParsers : allParsers;

    // Run the parsers, in order, until one of them succeeds
    plugins.sort(parsers);
    plugins.run(parsers, "parse", file)
      .then(onParsed, onError);

    function onParsed (parser) {
      if (!parser.plugin.allowEmpty && isEmpty(parser.result)) {
        reject(ono.syntax('Error parsing "%s" as %s. \nParsed value is empty', file.url, parser.plugin.name));
      }
      else {
        resolve(parser);
      }
    }

    function onError (err) {
      if (err) {
        err = err instanceof Error ? err : new Error(err);
        reject(ono.syntax(err, "Error parsing %s", file.url));
      }
      else {
        reject(ono.syntax("Unable to parse %s", file.url));
      }
    }
  });
}

/**
 * Determines whether the parsed value is "empty".
 *
 * @param {*} value
 * @returns {boolean}
 */
function isEmpty (value) {
  return value === undefined ||
    (typeof value === "object" && Object.keys(value).length === 0) ||
    (typeof value === "string" && value.trim().length === 0) ||
    (Buffer.isBuffer(value) && value.length === 0);
}

}).call(this,{"isBuffer":require("../node_modules/is-buffer/index.js")})

},{"../node_modules/is-buffer/index.js":32,"./util/plugins":17,"./util/url":18,"ono":64}],7:[function(require,module,exports){
(function (Buffer){
"use strict";

var BINARY_REGEXP = /\.(jpeg|jpg|gif|png|bmp|ico)$/i;

module.exports = {
  /**
   * The order that this parser will run, in relation to other parsers.
   *
   * @type {number}
   */
  order: 400,

  /**
   * Whether to allow "empty" files (zero bytes).
   *
   * @type {boolean}
   */
  allowEmpty: true,

  /**
   * Determines whether this parser can parse a given file reference.
   * Parsers that return true will be tried, in order, until one successfully parses the file.
   * Parsers that return false will be skipped, UNLESS all parsers returned false, in which case
   * every parser will be tried.
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
   * @returns {boolean}
   */
  canParse: function isBinary (file) {
    // Use this parser if the file is a Buffer, and has a known binary extension
    return Buffer.isBuffer(file.data) && BINARY_REGEXP.test(file.url);
  },

  /**
   * Parses the given data as a Buffer (byte array).
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
   * @returns {Promise<Buffer>}
   */
  parse: function parseBinary (file) {
    if (Buffer.isBuffer(file.data)) {
      return file.data;
    }
    else {
      // This will reject if data is anything other than a string or typed array
      return new Buffer(file.data);
    }
  }
};

}).call(this,require("buffer").Buffer)

},{"buffer":23}],8:[function(require,module,exports){
(function (Buffer){
"use strict";

module.exports = {
  /**
   * The order that this parser will run, in relation to other parsers.
   *
   * @type {number}
   */
  order: 100,

  /**
   * Whether to allow "empty" files. This includes zero-byte files, as well as empty JSON objects.
   *
   * @type {boolean}
   */
  allowEmpty: true,

  /**
   * Determines whether this parser can parse a given file reference.
   * Parsers that match will be tried, in order, until one successfully parses the file.
   * Parsers that don't match will be skipped, UNLESS none of the parsers match, in which case
   * every parser will be tried.
   *
   * @type {RegExp|string[]|function}
   */
  canParse: ".json",

  /**
   * Parses the given file as JSON
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
   * @returns {Promise}
   */
  parse: function parseJSON (file) {
    return new Promise(function (resolve, reject) {
      var data = file.data;
      if (Buffer.isBuffer(data)) {
        data = data.toString();
      }

      if (typeof data === "string") {
        if (data.trim().length === 0) {
          resolve(undefined);  // This mirrors the YAML behavior
        }
        else {
          resolve(JSON.parse(data));
        }
      }
      else {
        // data is already a JavaScript value (object, array, number, null, NaN, etc.)
        resolve(data);
      }
    });
  }
};

}).call(this,{"isBuffer":require("../../node_modules/is-buffer/index.js")})

},{"../../node_modules/is-buffer/index.js":32}],9:[function(require,module,exports){
(function (Buffer){
"use strict";

var TEXT_REGEXP = /\.(txt|htm|html|md|xml|js|min|map|css|scss|less|svg)$/i;

module.exports = {
  /**
   * The order that this parser will run, in relation to other parsers.
   *
   * @type {number}
   */
  order: 300,

  /**
   * Whether to allow "empty" files (zero bytes).
   *
   * @type {boolean}
   */
  allowEmpty: true,

  /**
   * The encoding that the text is expected to be in.
   *
   * @type {string}
   */
  encoding: "utf8",

  /**
   * Determines whether this parser can parse a given file reference.
   * Parsers that return true will be tried, in order, until one successfully parses the file.
   * Parsers that return false will be skipped, UNLESS all parsers returned false, in which case
   * every parser will be tried.
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
   * @returns {boolean}
   */
  canParse: function isText (file) {
    // Use this parser if the file is a string or Buffer, and has a known text-based extension
    return (typeof file.data === "string" || Buffer.isBuffer(file.data)) && TEXT_REGEXP.test(file.url);
  },

  /**
   * Parses the given file as text
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
   * @returns {Promise<string>}
   */
  parse: function parseText (file) {
    if (typeof file.data === "string") {
      return file.data;
    }
    else if (Buffer.isBuffer(file.data)) {
      return file.data.toString(this.encoding);
    }
    else {
      throw new Error("data is not text");
    }
  }
};

}).call(this,{"isBuffer":require("../../node_modules/is-buffer/index.js")})

},{"../../node_modules/is-buffer/index.js":32}],10:[function(require,module,exports){
(function (Buffer){
"use strict";

var YAML = require("../util/yaml");

module.exports = {
  /**
   * The order that this parser will run, in relation to other parsers.
   *
   * @type {number}
   */
  order: 200,

  /**
   * Whether to allow "empty" files. This includes zero-byte files, as well as empty JSON objects.
   *
   * @type {boolean}
   */
  allowEmpty: true,

  /**
   * Determines whether this parser can parse a given file reference.
   * Parsers that match will be tried, in order, until one successfully parses the file.
   * Parsers that don't match will be skipped, UNLESS none of the parsers match, in which case
   * every parser will be tried.
   *
   * @type {RegExp|string[]|function}
   */
  canParse: [".yaml", ".yml", ".json"],  // JSON is valid YAML

  /**
   * Parses the given file as YAML
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @param {*}      file.data      - The file contents. This will be whatever data type was returned by the resolver
   * @returns {Promise}
   */
  parse: function parseYAML (file) {
    return new Promise(function (resolve, reject) {
      var data = file.data;
      if (Buffer.isBuffer(data)) {
        data = data.toString();
      }

      if (typeof data === "string") {
        resolve(YAML.parse(data));
      }
      else {
        // data is already a JavaScript value (object, array, number, null, NaN, etc.)
        resolve(data);
      }
    });
  }
};

}).call(this,{"isBuffer":require("../../node_modules/is-buffer/index.js")})

},{"../../node_modules/is-buffer/index.js":32,"../util/yaml":19}],11:[function(require,module,exports){
"use strict";

module.exports = Pointer;

var $Ref = require("./ref"),
    url = require("./util/url"),
    ono = require("ono"),
    slashes = /\//g,
    tildes = /~/g,
    escapedSlash = /~1/g,
    escapedTilde = /~0/g;

/**
 * This class represents a single JSON pointer and its resolved value.
 *
 * @param {$Ref} $ref
 * @param {string} path
 * @param {string} [friendlyPath] - The original user-specified path (used for error messages)
 * @constructor
 */
function Pointer ($ref, path, friendlyPath) {
  /**
   * The {@link $Ref} object that contains this {@link Pointer} object.
   * @type {$Ref}
   */
  this.$ref = $ref;

  /**
   * The file path or URL, containing the JSON pointer in the hash.
   * This path is relative to the path of the main JSON schema file.
   * @type {string}
   */
  this.path = path;

  /**
   * The original path or URL, used for error messages.
   * @type {string}
   */
  this.originalPath = friendlyPath || path;

  /**
   * The value of the JSON pointer.
   * Can be any JSON type, not just objects. Unknown file types are represented as Buffers (byte arrays).
   * @type {?*}
   */
  this.value = undefined;

  /**
   * Indicates whether the pointer references itself.
   * @type {boolean}
   */
  this.circular = false;

  /**
   * The number of indirect references that were traversed to resolve the value.
   * Resolving a single pointer may require resolving multiple $Refs.
   * @type {number}
   */
  this.indirections = 0;
}

/**
 * Resolves the value of a nested property within the given object.
 *
 * @param {*} obj - The object that will be crawled
 * @param {$RefParserOptions} options
 *
 * @returns {Pointer}
 * Returns a JSON pointer whose {@link Pointer#value} is the resolved value.
 * If resolving this value required resolving other JSON references, then
 * the {@link Pointer#$ref} and {@link Pointer#path} will reflect the resolution path
 * of the resolved value.
 */
Pointer.prototype.resolve = function (obj, options) {
  var tokens = Pointer.parse(this.path);

  // Crawl the object, one token at a time
  this.value = obj;
  for (var i = 0; i < tokens.length; i++) {
    if (resolveIf$Ref(this, options)) {
      // The $ref path has changed, so append the remaining tokens to the path
      this.path = Pointer.join(this.path, tokens.slice(i));
    }

    var token = tokens[i];
    if (this.value[token] === undefined) {
      throw ono.syntax('Error resolving $ref pointer "%s". \nToken "%s" does not exist.', this.originalPath, token);
    }
    else {
      this.value = this.value[token];
    }
  }

  // Resolve the final value
  resolveIf$Ref(this, options);
  return this;
};

/**
 * Sets the value of a nested property within the given object.
 *
 * @param {*} obj - The object that will be crawled
 * @param {*} value - the value to assign
 * @param {$RefParserOptions} options
 *
 * @returns {*}
 * Returns the modified object, or an entirely new object if the entire object is overwritten.
 */
Pointer.prototype.set = function (obj, value, options) {
  var tokens = Pointer.parse(this.path);
  var token;

  if (tokens.length === 0) {
    // There are no tokens, replace the entire object with the new value
    this.value = value;
    return value;
  }

  // Crawl the object, one token at a time
  this.value = obj;
  for (var i = 0; i < tokens.length - 1; i++) {
    resolveIf$Ref(this, options);

    token = tokens[i];
    if (this.value && this.value[token] !== undefined) {
      // The token exists
      this.value = this.value[token];
    }
    else {
      // The token doesn't exist, so create it
      this.value = setValue(this, token, {});
    }
  }

  // Set the value of the final token
  resolveIf$Ref(this, options);
  token = tokens[tokens.length - 1];
  setValue(this, token, value);

  // Return the updated object
  return obj;
};

/**
 * Parses a JSON pointer (or a path containing a JSON pointer in the hash)
 * and returns an array of the pointer's tokens.
 * (e.g. "schema.json#/definitions/person/name" => ["definitions", "person", "name"])
 *
 * The pointer is parsed according to RFC 6901
 * {@link https://tools.ietf.org/html/rfc6901#section-3}
 *
 * @param {string} path
 * @returns {string[]}
 */
Pointer.parse = function (path) {
  // Get the JSON pointer from the path's hash
  var pointer = url.getHash(path).substr(1);

  // If there's no pointer, then there are no tokens,
  // so return an empty array
  if (!pointer) {
    return [];
  }

  // Split into an array
  pointer = pointer.split("/");

  // Decode each part, according to RFC 6901
  for (var i = 0; i < pointer.length; i++) {
    pointer[i] = decodeURIComponent(pointer[i].replace(escapedSlash, "/").replace(escapedTilde, "~"));
  }

  if (pointer[0] !== "") {
    throw ono.syntax('Invalid $ref pointer "%s". Pointers must begin with "#/"', pointer);
  }

  return pointer.slice(1);
};

/**
 * Creates a JSON pointer path, by joining one or more tokens to a base path.
 *
 * @param {string} base - The base path (e.g. "schema.json#/definitions/person")
 * @param {string|string[]} tokens - The token(s) to append (e.g. ["name", "first"])
 * @returns {string}
 */
Pointer.join = function (base, tokens) {
  // Ensure that the base path contains a hash
  if (base.indexOf("#") === -1) {
    base += "#";
  }

  // Append each token to the base path
  tokens = Array.isArray(tokens) ? tokens : [tokens];
  for (var i = 0; i < tokens.length; i++) {
    var token = tokens[i];
    // Encode the token, according to RFC 6901
    base += "/" + encodeURIComponent(token.replace(tildes, "~0").replace(slashes, "~1"));
  }

  return base;
};

/**
 * If the given pointer's {@link Pointer#value} is a JSON reference,
 * then the reference is resolved and {@link Pointer#value} is replaced with the resolved value.
 * In addition, {@link Pointer#path} and {@link Pointer#$ref} are updated to reflect the
 * resolution path of the new value.
 *
 * @param {Pointer} pointer
 * @param {$RefParserOptions} options
 * @returns {boolean} - Returns `true` if the resolution path changed
 */
function resolveIf$Ref (pointer, options) {
  // Is the value a JSON reference? (and allowed?)

  if ($Ref.isAllowed$Ref(pointer.value, options)) {
    var $refPath = url.resolve(pointer.path, pointer.value.$ref);

    if ($refPath === pointer.path) {
      // The value is a reference to itself, so there's nothing to do.
      pointer.circular = true;
    }
    else {
      var resolved = pointer.$ref.$refs._resolve($refPath, options);
      pointer.indirections += resolved.indirections + 1;

      if ($Ref.isExtended$Ref(pointer.value)) {
        // This JSON reference "extends" the resolved value, rather than simply pointing to it.
        // So the resolved path does NOT change.  Just the value does.
        pointer.value = $Ref.dereference(pointer.value, resolved.value);
        return false;
      }
      else {
        // Resolve the reference
        pointer.$ref = resolved.$ref;
        pointer.path = resolved.path;
        pointer.value = resolved.value;
      }

      return true;
    }
  }
}

/**
 * Sets the specified token value of the {@link Pointer#value}.
 *
 * The token is evaluated according to RFC 6901.
 * {@link https://tools.ietf.org/html/rfc6901#section-4}
 *
 * @param {Pointer} pointer - The JSON Pointer whose value will be modified
 * @param {string} token - A JSON Pointer token that indicates how to modify `obj`
 * @param {*} value - The value to assign
 * @returns {*} - Returns the assigned value
 */
function setValue (pointer, token, value) {
  if (pointer.value && typeof pointer.value === "object") {
    if (token === "-" && Array.isArray(pointer.value)) {
      pointer.value.push(value);
    }
    else {
      pointer.value[token] = value;
    }
  }
  else {
    throw ono.syntax('Error assigning $ref pointer "%s". \nCannot set "%s" of a non-object.', pointer.path, token);
  }
  return value;
}

},{"./ref":12,"./util/url":18,"ono":64}],12:[function(require,module,exports){
"use strict";

module.exports = $Ref;

var Pointer = require("./pointer");

/**
 * This class represents a single JSON reference and its resolved value.
 *
 * @constructor
 */
function $Ref () {
  /**
   * The file path or URL of the referenced file.
   * This path is relative to the path of the main JSON schema file.
   *
   * This path does NOT contain document fragments (JSON pointers). It always references an ENTIRE file.
   * Use methods such as {@link $Ref#get}, {@link $Ref#resolve}, and {@link $Ref#exists} to get
   * specific JSON pointers within the file.
   *
   * @type {string}
   */
  this.path = undefined;

  /**
   * The resolved value of the JSON reference.
   * Can be any JSON type, not just objects. Unknown file types are represented as Buffers (byte arrays).
   * @type {?*}
   */
  this.value = undefined;

  /**
   * The {@link $Refs} object that contains this {@link $Ref} object.
   * @type {$Refs}
   */
  this.$refs = undefined;

  /**
   * Indicates the type of {@link $Ref#path} (e.g. "file", "http", etc.)
   * @type {?string}
   */
  this.pathType = undefined;
}

/**
 * Determines whether the given JSON reference exists within this {@link $Ref#value}.
 *
 * @param {string} path - The full path being resolved, optionally with a JSON pointer in the hash
 * @param {$RefParserOptions} options
 * @returns {boolean}
 */
$Ref.prototype.exists = function (path, options) {
  try {
    this.resolve(path, options);
    return true;
  }
  catch (e) {
    return false;
  }
};

/**
 * Resolves the given JSON reference within this {@link $Ref#value} and returns the resolved value.
 *
 * @param {string} path - The full path being resolved, optionally with a JSON pointer in the hash
 * @param {$RefParserOptions} options
 * @returns {*} - Returns the resolved value
 */
$Ref.prototype.get = function (path, options) {
  return this.resolve(path, options).value;
};

/**
 * Resolves the given JSON reference within this {@link $Ref#value}.
 *
 * @param {string} path - The full path being resolved, optionally with a JSON pointer in the hash
 * @param {$RefParserOptions} options
 * @param {string} [friendlyPath] - The original user-specified path (used for error messages)
 * @returns {Pointer}
 */
$Ref.prototype.resolve = function (path, options, friendlyPath) {
  var pointer = new Pointer(this, path, friendlyPath);
  return pointer.resolve(this.value, options);
};

/**
 * Sets the value of a nested property within this {@link $Ref#value}.
 * If the property, or any of its parents don't exist, they will be created.
 *
 * @param {string} path - The full path of the property to set, optionally with a JSON pointer in the hash
 * @param {*} value - The value to assign
 */
$Ref.prototype.set = function (path, value) {
  var pointer = new Pointer(this, path);
  this.value = pointer.set(this.value, value);
};

/**
 * Determines whether the given value is a JSON reference.
 *
 * @param {*} value - The value to inspect
 * @returns {boolean}
 */
$Ref.is$Ref = function (value) {
  return value && typeof value === "object" && typeof value.$ref === "string" && value.$ref.length > 0;
};

/**
 * Determines whether the given value is an external JSON reference.
 *
 * @param {*} value - The value to inspect
 * @returns {boolean}
 */
$Ref.isExternal$Ref = function (value) {
  return $Ref.is$Ref(value) && value.$ref[0] !== "#";
};

/**
 * Determines whether the given value is a JSON reference, and whether it is allowed by the options.
 * For example, if it references an external file, then options.resolve.external must be true.
 *
 * @param {*} value - The value to inspect
 * @param {$RefParserOptions} options
 * @returns {boolean}
 */
$Ref.isAllowed$Ref = function (value, options) {
  if ($Ref.is$Ref(value)) {
    if (value.$ref.substr(0, 2) === "#/" || value.$ref === "#") {
      // It's a JSON Pointer reference, which is always allowed
      return true;
    }
    else if (value.$ref[0] !== "#" && (!options || options.resolve.external)) {
      // It's an external reference, which is allowed by the options
      return true;
    }
  }
};

/**
 * Determines whether the given value is a JSON reference that "extends" its resolved value.
 * That is, it has extra properties (in addition to "$ref"), so rather than simply pointing to
 * an existing value, this $ref actually creates a NEW value that is a shallow copy of the resolved
 * value, plus the extra properties.
 *
 * @example:
 *  {
 *    person: {
 *      properties: {
 *        firstName: { type: string }
 *        lastName: { type: string }
 *      }
 *    }
 *    employee: {
 *      properties: {
 *        $ref: #/person/properties
 *        salary: { type: number }
 *      }
 *    }
 *  }
 *
 *  In this example, "employee" is an extended $ref, since it extends "person" with an additional
 *  property (salary).  The result is a NEW value that looks like this:
 *
 *  {
 *    properties: {
 *      firstName: { type: string }
 *      lastName: { type: string }
 *      salary: { type: number }
 *    }
 *  }
 *
 * @param {*} value - The value to inspect
 * @returns {boolean}
 */
$Ref.isExtended$Ref = function (value) {
  return $Ref.is$Ref(value) && Object.keys(value).length > 1;
};

/**
 * Returns the resolved value of a JSON Reference.
 * If necessary, the resolved value is merged with the JSON Reference to create a new object
 *
 * @example:
 *  {
 *    person: {
 *      properties: {
 *        firstName: { type: string }
 *        lastName: { type: string }
 *      }
 *    }
 *    employee: {
 *      properties: {
 *        $ref: #/person/properties
 *        salary: { type: number }
 *      }
 *    }
 *  }
 *
 *  When "person" and "employee" are merged, you end up with the following object:
 *
 *  {
 *    properties: {
 *      firstName: { type: string }
 *      lastName: { type: string }
 *      salary: { type: number }
 *    }
 *  }
 *
 * @param {object} $ref - The JSON reference object (the one with the "$ref" property)
 * @param {*} resolvedValue - The resolved value, which can be any type
 * @returns {*} - Returns the dereferenced value
 */
$Ref.dereference = function ($ref, resolvedValue) {
  if (resolvedValue && typeof resolvedValue === "object" && $Ref.isExtended$Ref($ref)) {
    var merged = {};
    Object.keys($ref).forEach(function (key) {
      if (key !== "$ref") {
        merged[key] = $ref[key];
      }
    });
    Object.keys(resolvedValue).forEach(function (key) {
      if (!(key in merged)) {
        merged[key] = resolvedValue[key];
      }
    });
    return merged;
  }
  else {
    // Completely replace the original reference with the resolved value
    return resolvedValue;
  }
};

},{"./pointer":11}],13:[function(require,module,exports){
"use strict";

var ono = require("ono"),
    $Ref = require("./ref"),
    url = require("./util/url");

module.exports = $Refs;

/**
 * This class is a map of JSON references and their resolved values.
 */
function $Refs () {
  /**
   * Indicates whether the schema contains any circular references.
   *
   * @type {boolean}
   */
  this.circular = false;

  /**
   * A map of paths/urls to {@link $Ref} objects
   *
   * @type {object}
   * @protected
   */
  this._$refs = {};

  /**
   * The {@link $Ref} object that is the root of the JSON schema.
   *
   * @type {$Ref}
   * @protected
   */
  this._root$Ref = null;
}

/**
 * Returns the paths of all the files/URLs that are referenced by the JSON schema,
 * including the schema itself.
 *
 * @param {...string|string[]} [types] - Only return paths of the given types ("file", "http", etc.)
 * @returns {string[]}
 */
$Refs.prototype.paths = function (types) {
  var paths = getPaths(this._$refs, arguments);
  return paths.map(function (path) {
    return path.decoded;
  });
};

/**
 * Returns the map of JSON references and their resolved values.
 *
 * @param {...string|string[]} [types] - Only return references of the given types ("file", "http", etc.)
 * @returns {object}
 */
$Refs.prototype.values = function (types) {
  var $refs = this._$refs;
  var paths = getPaths($refs, arguments);
  return paths.reduce(function (obj, path) {
    obj[path.decoded] = $refs[path.encoded].value;
    return obj;
  }, {});
};

/**
 * Returns a POJO (plain old JavaScript object) for serialization as JSON.
 *
 * @returns {object}
 */
$Refs.prototype.toJSON = $Refs.prototype.values;

/**
 * Determines whether the given JSON reference exists.
 *
 * @param {string} path - The path being resolved, optionally with a JSON pointer in the hash
 * @param {$RefParserOptions} [options]
 * @returns {boolean}
 */
$Refs.prototype.exists = function (path, options) {
  try {
    this._resolve(path, options);
    return true;
  }
  catch (e) {
    return false;
  }
};

/**
 * Resolves the given JSON reference and returns the resolved value.
 *
 * @param {string} path - The path being resolved, with a JSON pointer in the hash
 * @param {$RefParserOptions} [options]
 * @returns {*} - Returns the resolved value
 */
$Refs.prototype.get = function (path, options) {
  return this._resolve(path, options).value;
};

/**
 * Sets the value of a nested property within this {@link $Ref#value}.
 * If the property, or any of its parents don't exist, they will be created.
 *
 * @param {string} path - The path of the property to set, optionally with a JSON pointer in the hash
 * @param {*} value - The value to assign
 */
$Refs.prototype.set = function (path, value) {
  var absPath = url.resolve(this._root$Ref.path, path);
  var withoutHash = url.stripHash(absPath);
  var $ref = this._$refs[withoutHash];

  if (!$ref) {
    throw ono('Error resolving $ref pointer "%s". \n"%s" not found.', path, withoutHash);
  }

  $ref.set(absPath, value);
};

/**
 * Creates a new {@link $Ref} object and adds it to this {@link $Refs} object.
 *
 * @param {string} path  - The file path or URL of the referenced file
 */
$Refs.prototype._add = function (path) {
  var withoutHash = url.stripHash(path);

  var $ref = new $Ref();
  $ref.path = withoutHash;
  $ref.$refs = this;

  this._$refs[withoutHash] = $ref;
  this._root$Ref = this._root$Ref || $ref;

  return $ref;
};

/**
 * Resolves the given JSON reference.
 *
 * @param {string} path - The path being resolved, optionally with a JSON pointer in the hash
 * @param {$RefParserOptions} [options]
 * @returns {Pointer}
 * @protected
 */
$Refs.prototype._resolve = function (path, options) {
  var absPath = url.resolve(this._root$Ref.path, path);
  var withoutHash = url.stripHash(absPath);
  var $ref = this._$refs[withoutHash];

  if (!$ref) {
    throw ono('Error resolving $ref pointer "%s". \n"%s" not found.', path, withoutHash);
  }

  return $ref.resolve(absPath, options, path);
};

/**
 * Returns the specified {@link $Ref} object, or undefined.
 *
 * @param {string} path - The path being resolved, optionally with a JSON pointer in the hash
 * @returns {$Ref|undefined}
 * @protected
 */
$Refs.prototype._get$Ref = function (path) {
  path = url.resolve(this._root$Ref.path, path);
  var withoutHash = url.stripHash(path);
  return this._$refs[withoutHash];
};

/**
 * Returns the encoded and decoded paths keys of the given object.
 *
 * @param {object} $refs - The object whose keys are URL-encoded paths
 * @param {...string|string[]} [types] - Only return paths of the given types ("file", "http", etc.)
 * @returns {object[]}
 */
function getPaths ($refs, types) {
  var paths = Object.keys($refs);

  // Filter the paths by type
  types = Array.isArray(types[0]) ? types[0] : Array.prototype.slice.call(types);
  if (types.length > 0 && types[0]) {
    paths = paths.filter(function (key) {
      return types.indexOf($refs[key].pathType) !== -1;
    });
  }

  // Decode local filesystem paths
  return paths.map(function (path) {
    return {
      encoded: path,
      decoded: $refs[path].pathType === "file" ? url.toFileSystemPath(path, true) : path
    };
  });
}

},{"./ref":12,"./util/url":18,"ono":64}],14:[function(require,module,exports){
"use strict";

var $Ref = require("./ref"),
    Pointer = require("./pointer"),
    parse = require("./parse"),
    url = require("./util/url");

module.exports = resolveExternal;

/**
 * Crawls the JSON schema, finds all external JSON references, and resolves their values.
 * This method does not mutate the JSON schema. The resolved values are added to {@link $RefParser#$refs}.
 *
 * NOTE: We only care about EXTERNAL references here. INTERNAL references are only relevant when dereferencing.
 *
 * @param {$RefParser} parser
 * @param {$RefParserOptions} options
 *
 * @returns {Promise}
 * The promise resolves once all JSON references in the schema have been resolved,
 * including nested references that are contained in externally-referenced files.
 */
function resolveExternal (parser, options) {
  if (!options.resolve.external) {
    // Nothing to resolve, so exit early
    return Promise.resolve();
  }

  try {
    // console.log('Resolving $ref pointers in %s', parser.$refs._root$Ref.path);
    var promises = crawl(parser.schema, parser.$refs._root$Ref.path + "#", parser.$refs, options);
    return Promise.all(promises);
  }
  catch (e) {
    return Promise.reject(e);
  }
}

/**
 * Recursively crawls the given value, and resolves any external JSON references.
 *
 * @param {*} obj - The value to crawl. If it's not an object or array, it will be ignored.
 * @param {string} path - The full path of `obj`, possibly with a JSON Pointer in the hash
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 *
 * @returns {Promise[]}
 * Returns an array of promises. There will be one promise for each JSON reference in `obj`.
 * If `obj` does not contain any JSON references, then the array will be empty.
 * If any of the JSON references point to files that contain additional JSON references,
 * then the corresponding promise will internally reference an array of promises.
 */
function crawl (obj, path, $refs, options) {
  var promises = [];

  if (obj && typeof obj === "object") {
    if ($Ref.isExternal$Ref(obj)) {
      promises.push(resolve$Ref(obj, path, $refs, options));
    }
    else {
      Object.keys(obj).forEach(function (key) {
        var keyPath = Pointer.join(path, key);
        var value = obj[key];

        if ($Ref.isExternal$Ref(value)) {
          promises.push(resolve$Ref(value, keyPath, $refs, options));
        }
        else {
          promises = promises.concat(crawl(value, keyPath, $refs, options));
        }
      });
    }
  }

  return promises;
}

/**
 * Resolves the given JSON Reference, and then crawls the resulting value.
 *
 * @param {{$ref: string}} $ref - The JSON Reference to resolve
 * @param {string} path - The full path of `$ref`, possibly with a JSON Pointer in the hash
 * @param {$Refs} $refs
 * @param {$RefParserOptions} options
 *
 * @returns {Promise}
 * The promise resolves once all JSON references in the object have been resolved,
 * including nested references that are contained in externally-referenced files.
 */
function resolve$Ref ($ref, path, $refs, options) {
  // console.log('Resolving $ref pointer "%s" at %s', $ref.$ref, path);

  var resolvedPath = url.resolve(path, $ref.$ref);
  var withoutHash = url.stripHash(resolvedPath);

  // Do we already have this $ref?
  $ref = $refs._$refs[withoutHash];
  if ($ref) {
    // We've already parsed this $ref, so use the existing value
    return Promise.resolve($ref.value);
  }

  // Parse the $referenced file/url
  return parse(resolvedPath, $refs, options)
    .then(function (result) {
      // Crawl the parsed value
      // console.log('Resolving $ref pointers in %s', withoutHash);
      var promises = crawl(result, withoutHash + "#", $refs, options);
      return Promise.all(promises);
    });
}

},{"./parse":6,"./pointer":11,"./ref":12,"./util/url":18}],15:[function(require,module,exports){
"use strict";
var fs = require("fs"),
    ono = require("ono"),
    url = require("../util/url");

module.exports = {
  /**
   * The order that this resolver will run, in relation to other resolvers.
   *
   * @type {number}
   */
  order: 100,

  /**
   * Determines whether this resolver can read a given file reference.
   * Resolvers that return true will be tried, in order, until one successfully resolves the file.
   * Resolvers that return false will not be given a chance to resolve the file.
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @returns {boolean}
   */
  canRead: function isFile (file) {
    return url.isFileSystemPath(file.url);
  },

  /**
   * Reads the given file and returns its raw contents as a Buffer.
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @returns {Promise<Buffer>}
   */
  read: function readFile (file) {
    return new Promise(function (resolve, reject) {
      var path;
      try {
        path = url.toFileSystemPath(file.url);
      }
      catch (err) {
        reject(ono.uri(err, "Malformed URI: %s", file.url));
      }

      // console.log('Opening file: %s', path);

      try {
        fs.readFile(path, function (err, data) {
          if (err) {
            reject(ono(err, 'Error opening file "%s"', path));
          }
          else {
            resolve(data);
          }
        });
      }
      catch (err) {
        reject(ono(err, 'Error opening file "%s"', path));
      }
    });
  }
};

},{"../util/url":18,"fs":21,"ono":64}],16:[function(require,module,exports){
(function (process,Buffer){
"use strict";

var http = require("http"),
    https = require("https"),
    ono = require("ono"),
    url = require("../util/url");

module.exports = {
  /**
   * The order that this resolver will run, in relation to other resolvers.
   *
   * @type {number}
   */
  order: 200,

  /**
   * HTTP headers to send when downloading files.
   *
   * @example:
   * {
   *   "User-Agent": "JSON Schema $Ref Parser",
   *   Accept: "application/json"
   * }
   *
   * @type {object}
   */
  headers: null,

  /**
   * HTTP request timeout (in milliseconds).
   *
   * @type {number}
   */
  timeout: 5000, // 5 seconds

  /**
   * The maximum number of HTTP redirects to follow.
   * To disable automatic following of redirects, set this to zero.
   *
   * @type {number}
   */
  redirects: 5,

  /**
   * The `withCredentials` option of XMLHttpRequest.
   * Set this to `true` if you're downloading files from a CORS-enabled server that requires authentication
   *
   * @type {boolean}
   */
  withCredentials: false,

  /**
   * Determines whether this resolver can read a given file reference.
   * Resolvers that return true will be tried in order, until one successfully resolves the file.
   * Resolvers that return false will not be given a chance to resolve the file.
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @returns {boolean}
   */
  canRead: function isHttp (file) {
    return url.isHttp(file.url);
  },

  /**
   * Reads the given URL and returns its raw contents as a Buffer.
   *
   * @param {object} file           - An object containing information about the referenced file
   * @param {string} file.url       - The full URL of the referenced file
   * @param {string} file.extension - The lowercased file extension (e.g. ".txt", ".html", etc.)
   * @returns {Promise<Buffer>}
   */
  read: function readHttp (file) {
    var u = url.parse(file.url);

    if (process.browser && !u.protocol) {
      // Use the protocol of the current page
      u.protocol = url.parse(location.href).protocol;
    }

    return download(u, this);
  }
};

/**
 * Downloads the given file.
 *
 * @param {Url|string} u        - The url to download (can be a parsed {@link Url} object)
 * @param {object} httpOptions  - The `options.resolve.http` object
 * @param {number} [redirects]  - The redirect URLs that have already been followed
 *
 * @returns {Promise<Buffer>}
 * The promise resolves with the raw downloaded data, or rejects if there is an HTTP error.
 */
function download (u, httpOptions, redirects) {
  return new Promise(function (resolve, reject) {
    u = url.parse(u);
    redirects = redirects || [];
    redirects.push(u.href);

    get(u, httpOptions)
      .then(function (res) {
        if (res.statusCode >= 400) {
          throw ono({ status: res.statusCode }, "HTTP ERROR %d", res.statusCode);
        }
        else if (res.statusCode >= 300) {
          if (redirects.length > httpOptions.redirects) {
            reject(ono({ status: res.statusCode }, "Error downloading %s. \nToo many redirects: \n  %s",
              redirects[0], redirects.join(" \n  ")));
          }
          else if (!res.headers.location) {
            throw ono({ status: res.statusCode }, "HTTP %d redirect with no location header", res.statusCode);
          }
          else {
            // console.log('HTTP %d redirect %s -> %s', res.statusCode, u.href, res.headers.location);
            var redirectTo = url.resolve(u, res.headers.location);
            download(redirectTo, httpOptions, redirects).then(resolve, reject);
          }
        }
        else {
          resolve(res.body || new Buffer(0));
        }
      })
      .catch(function (err) {
        reject(ono(err, "Error downloading", u.href));
      });
  });
}

/**
 * Sends an HTTP GET request.
 *
 * @param {Url} u - A parsed {@link Url} object
 * @param {object} httpOptions - The `options.resolve.http` object
 *
 * @returns {Promise<Response>}
 * The promise resolves with the HTTP Response object.
 */
function get (u, httpOptions) {
  return new Promise(function (resolve, reject) {
    // console.log('GET', u.href);

    var protocol = u.protocol === "https:" ? https : http;
    var req = protocol.get({
      hostname: u.hostname,
      port: u.port,
      path: u.path,
      auth: u.auth,
      protocol: u.protocol,
      headers: httpOptions.headers || {},
      withCredentials: httpOptions.withCredentials
    });

    if (typeof req.setTimeout === "function") {
      req.setTimeout(httpOptions.timeout);
    }

    req.on("timeout", function () {
      req.abort();
    });

    req.on("error", reject);

    req.once("response", function (res) {
      res.body = new Buffer(0);

      res.on("data", function (data) {
        res.body = Buffer.concat([res.body, new Buffer(data)]);
      });

      res.on("error", reject);

      res.on("end", function () {
        resolve(res);
      });
    });
  });
}

}).call(this,require('_process'),require("buffer").Buffer)

},{"../util/url":18,"_process":66,"buffer":23,"http":80,"https":29,"ono":64}],17:[function(require,module,exports){
"use strict";

/**
 * Returns the given plugins as an array, rather than an object map.
 * All other methods in this module expect an array of plugins rather than an object map.
 *
 * @param  {object} plugins - A map of plugin objects
 * @return {object[]}
 */
exports.all = function (plugins) {
  return Object.keys(plugins)
    .filter(function (key) {
      return typeof plugins[key] === "object";
    })
    .map(function (key) {
      plugins[key].name = key;
      return plugins[key];
    });
};

/**
 * Filters the given plugins, returning only the ones return `true` for the given method.
 *
 * @param  {object[]} plugins - An array of plugin objects
 * @param  {string}   method  - The name of the filter method to invoke for each plugin
 * @param  {object}   file    - A file info object, which will be passed to each method
 * @return {object[]}
 */
exports.filter = function (plugins, method, file) {
  return plugins
    .filter(function (plugin) {
      return !!getResult(plugin, method, file);
    });
};

/**
 * Sorts the given plugins, in place, by their `order` property.
 *
 * @param {object[]} plugins - An array of plugin objects
 * @returns {object[]}
 */
exports.sort = function (plugins) {
  plugins.forEach(function (plugin) {
    plugin.order = plugin.order || Number.MAX_SAFE_INTEGER;
  });

  return plugins.sort(function (a, b) { return a.order - b.order; });
};

/**
 * Runs the specified method of the given plugins, in order, until one of them returns a successful result.
 * Each method can return a synchronous value, a Promise, or call an error-first callback.
 * If the promise resolves successfully, or the callback is called without an error, then the result
 * is immediately returned and no further plugins are called.
 * If the promise rejects, or the callback is called with an error, then the next plugin is called.
 * If ALL plugins fail, then the last error is thrown.
 *
 * @param {object[]}  plugins - An array of plugin objects
 * @param {string}    method  - The name of the method to invoke for each plugin
 * @param {object}    file    - A file info object, which will be passed to each method
 * @returns {Promise}
 */
exports.run = function (plugins, method, file) {
  var plugin, lastError, index = 0;

  return new Promise(function (resolve, reject) {
    runNextPlugin();

    function runNextPlugin () {
      plugin = plugins[index++];
      if (!plugin) {
        // There are no more functions, so re-throw the last error
        return reject(lastError);
      }

      try {
        // console.log('  %s', plugin.name);
        var result = getResult(plugin, method, file, callback);
        if (result && typeof result.then === "function") {
          // A promise was returned
          result.then(onSuccess, onError);
        }
        else if (result !== undefined) {
          // A synchronous result was returned
          onSuccess(result);
        }
        // else { the callback will be called }
      }
      catch (e) {
        onError(e);
      }
    }

    function callback (err, result) {
      if (err) {
        onError(err);
      }
      else {
        onSuccess(result);
      }
    }

    function onSuccess (result) {
      // console.log('    success');
      resolve({
        plugin: plugin,
        result: result
      });
    }

    function onError (err) {
      // console.log('    %s', err.message || err);
      lastError = err;
      runNextPlugin();
    }
  });
};

/**
 * Returns the value of the given property.
 * If the property is a function, then the result of the function is returned.
 * If the value is a RegExp, then it will be tested against the file URL.
 * If the value is an aray, then it will be compared against the file extension.
 *
 * @param   {object}   obj        - The object whose property/method is called
 * @param   {string}   prop       - The name of the property/method to invoke
 * @param   {object}   file       - A file info object, which will be passed to the method
 * @param   {function} [callback] - A callback function, which will be passed to the method
 * @returns {*}
 */
function getResult (obj, prop, file, callback) {
  var value = obj[prop];

  if (typeof value === "function") {
    return value.apply(obj, [file, callback]);
  }

  if (!callback) {
    // The synchronous plugin functions (canParse and canRead)
    // allow a "shorthand" syntax, where the user can match
    // files by RegExp or by file extension.
    if (value instanceof RegExp) {
      return value.test(file.url);
    }
    else if (typeof value === "string") {
      return value === file.extension;
    }
    else if (Array.isArray(value)) {
      return value.indexOf(file.extension) !== -1;
    }
  }

  return value;
}

},{}],18:[function(require,module,exports){
(function (process){
"use strict";

var isWindows = /^win/.test(process.platform),
    forwardSlashPattern = /\//g,
    protocolPattern = /^(\w{2,}):\/\//i,
    url = module.exports;

// RegExp patterns to URL-encode special characters in local filesystem paths
var urlEncodePatterns = [
  /\?/g, "%3F",
  /\#/g, "%23",
];

// RegExp patterns to URL-decode special characters for local filesystem paths
var urlDecodePatterns = [
  /\%23/g, "#",
  /\%24/g, "$",
  /\%26/g, "&",
  /\%2C/g, ",",
  /\%40/g, "@"
];

exports.parse = require("url").parse;
exports.resolve = require("url").resolve;

/**
 * Returns the current working directory (in Node) or the current page URL (in browsers).
 *
 * @returns {string}
 */
exports.cwd = function cwd () {
  return process.browser ? location.href : process.cwd() + "/";
};

/**
 * Returns the protocol of the given URL, or `undefined` if it has no protocol.
 *
 * @param   {string} path
 * @returns {?string}
 */
exports.getProtocol = function getProtocol (path) {
  var match = protocolPattern.exec(path);
  if (match) {
    return match[1].toLowerCase();
  }
};

/**
 * Returns the lowercased file extension of the given URL,
 * or an empty string if it has no extension.
 *
 * @param   {string} path
 * @returns {string}
 */
exports.getExtension = function getExtension (path) {
  var lastDot = path.lastIndexOf(".");
  if (lastDot >= 0) {
    return path.substr(lastDot).toLowerCase();
  }
  return "";
};

/**
 * Returns the hash (URL fragment), of the given path.
 * If there is no hash, then the root hash ("#") is returned.
 *
 * @param   {string} path
 * @returns {string}
 */
exports.getHash = function getHash (path) {
  var hashIndex = path.indexOf("#");
  if (hashIndex >= 0) {
    return path.substr(hashIndex);
  }
  return "#";
};

/**
 * Removes the hash (URL fragment), if any, from the given path.
 *
 * @param   {string} path
 * @returns {string}
 */
exports.stripHash = function stripHash (path) {
  var hashIndex = path.indexOf("#");
  if (hashIndex >= 0) {
    path = path.substr(0, hashIndex);
  }
  return path;
};

/**
 * Determines whether the given path is an HTTP(S) URL.
 *
 * @param   {string} path
 * @returns {boolean}
 */
exports.isHttp = function isHttp (path) {
  var protocol = url.getProtocol(path);
  if (protocol === "http" || protocol === "https") {
    return true;
  }
  else if (protocol === undefined) {
    // There is no protocol.  If we're running in a browser, then assume it's HTTP.
    return process.browser;
  }
  else {
    // It's some other protocol, such as "ftp://", "mongodb://", etc.
    return false;
  }
};

/**
 * Determines whether the given path is a filesystem path.
 * This includes "file://" URLs.
 *
 * @param   {string} path
 * @returns {boolean}
 */
exports.isFileSystemPath = function isFileSystemPath (path) {
  if (process.browser) {
    // We're running in a browser, so assume that all paths are URLs.
    // This way, even relative paths will be treated as URLs rather than as filesystem paths
    return false;
  }

  var protocol = url.getProtocol(path);
  return protocol === undefined || protocol === "file";
};

/**
 * Converts a filesystem path to a properly-encoded URL.
 *
 * This is intended to handle situations where JSON Schema $Ref Parser is called
 * with a filesystem path that contains characters which are not allowed in URLs.
 *
 * @example
 * The following filesystem paths would be converted to the following URLs:
 *
 *    <"!@#$%^&*+=?'>.json              ==>   %3C%22!@%23$%25%5E&*+=%3F\'%3E.json
 *    C:\\My Documents\\File (1).json   ==>   C:/My%20Documents/File%20(1).json
 *    file://Project #42/file.json      ==>   file://Project%20%2342/file.json
 *
 * @param {string} path
 * @returns {string}
 */
exports.fromFileSystemPath = function fromFileSystemPath (path) {
  // Step 1: On Windows, replace backslashes with forward slashes,
  // rather than encoding them as "%5C"
  if (isWindows) {
    path = path.replace(/\\/g, "/");
  }

  // Step 2: `encodeURI` will take care of MOST characters
  path = encodeURI(path);

  // Step 3: Manually encode characters that are not encoded by `encodeURI`.
  // This includes characters such as "#" and "?", which have special meaning in URLs,
  // but are just normal characters in a filesystem path.
  for (var i = 0; i < urlEncodePatterns.length; i += 2) {
    path = path.replace(urlEncodePatterns[i], urlEncodePatterns[i + 1]);
  }

  return path;
};

/**
 * Converts a URL to a local filesystem path.
 *
 * @param {string}  path
 * @param {boolean} [keepFileProtocol] - If true, then "file://" will NOT be stripped
 * @returns {string}
 */
exports.toFileSystemPath = function toFileSystemPath (path, keepFileProtocol) {
  // Step 1: `decodeURI` will decode characters such as Cyrillic characters, spaces, etc.
  path = decodeURI(path);

  // Step 2: Manually decode characters that are not decoded by `decodeURI`.
  // This includes characters such as "#" and "?", which have special meaning in URLs,
  // but are just normal characters in a filesystem path.
  for (var i = 0; i < urlDecodePatterns.length; i += 2) {
    path = path.replace(urlDecodePatterns[i], urlDecodePatterns[i + 1]);
  }

  // Step 3: If it's a "file://" URL, then format it consistently
  // or convert it to a local filesystem path
  var isFileUrl = path.substr(0, 7).toLowerCase() === "file://";
  if (isFileUrl) {
    // Strip-off the protocol, and the initial "/", if there is one
    path = path[7] === "/" ? path.substr(8) : path.substr(7);

    // insert a colon (":") after the drive letter on Windows
    if (isWindows && path[1] === "/") {
      path = path[0] + ":" + path.substr(1);
    }

    if (keepFileProtocol) {
      // Return the consistently-formatted "file://" URL
      path = "file:///" + path;
    }
    else {
      // Convert the "file://" URL to a local filesystem path.
      // On Windows, it will start with something like "C:/".
      // On Posix, it will start with "/"
      isFileUrl = false;
      path = isWindows ? path : "/" + path;
    }
  }

  // Step 4: Normalize Windows paths (unless it's a "file://" URL)
  if (isWindows && !isFileUrl) {
    // Replace forward slashes with backslashes
    path = path.replace(forwardSlashPattern, "\\");

    // Capitalize the drive letter
    if (path.substr(1, 2) === ":\\") {
      path = path[0].toUpperCase() + path.substr(1);
    }
  }

  return path;
};

}).call(this,require('_process'))

},{"_process":66,"url":87}],19:[function(require,module,exports){
/* eslint lines-around-comment: [2, {beforeBlockComment: false}] */
"use strict";

var yaml = require("js-yaml"),
    ono = require("ono");

/**
 * Simple YAML parsing functions, similar to {@link JSON.parse} and {@link JSON.stringify}
 */
module.exports = {
  /**
   * Parses a YAML string and returns the value.
   *
   * @param {string} text - The YAML string to be parsed
   * @param {function} [reviver] - Not currently supported. Provided for consistency with {@link JSON.parse}
   * @returns {*}
   */
  parse: function yamlParse (text, reviver) {
    try {
      return yaml.safeLoad(text);
    }
    catch (e) {
      if (e instanceof Error) {
        throw e;
      }
      else {
        // https://github.com/nodeca/js-yaml/issues/153
        throw ono(e, e.message);
      }
    }
  },

  /**
   * Converts a JavaScript value to a YAML string.
   *
   * @param   {*} value - The value to convert to YAML
   * @param   {function|array} replacer - Not currently supported. Provided for consistency with {@link JSON.stringify}
   * @param   {string|number} space - The number of spaces to use for indentation, or a string containing the number of spaces.
   * @returns {string}
   */
  stringify: function yamlStringify (value, replacer, space) {
    try {
      var indent = (typeof space === "string" ? space.length : space) || 2;
      return yaml.safeDump(value, { indent: indent });
    }
    catch (e) {
      if (e instanceof Error) {
        throw e;
      }
      else {
        // https://github.com/nodeca/js-yaml/issues/153
        throw ono(e, e.message);
      }
    }
  }
};

},{"js-yaml":34,"ono":64}],20:[function(require,module,exports){
'use strict'

exports.byteLength = byteLength
exports.toByteArray = toByteArray
exports.fromByteArray = fromByteArray

var lookup = []
var revLookup = []
var Arr = typeof Uint8Array !== 'undefined' ? Uint8Array : Array

var code = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
for (var i = 0, len = code.length; i < len; ++i) {
  lookup[i] = code[i]
  revLookup[code.charCodeAt(i)] = i
}

// Support decoding URL-safe base64 strings, as Node.js does.
// See: https://en.wikipedia.org/wiki/Base64#URL_applications
revLookup['-'.charCodeAt(0)] = 62
revLookup['_'.charCodeAt(0)] = 63

function getLens (b64) {
  var len = b64.length

  if (len % 4 > 0) {
    throw new Error('Invalid string. Length must be a multiple of 4')
  }

  // Trim off extra bytes after placeholder bytes are found
  // See: https://github.com/beatgammit/base64-js/issues/42
  var validLen = b64.indexOf('=')
  if (validLen === -1) validLen = len

  var placeHoldersLen = validLen === len
    ? 0
    : 4 - (validLen % 4)

  return [validLen, placeHoldersLen]
}

// base64 is 4/3 + up to two characters of the original data
function byteLength (b64) {
  var lens = getLens(b64)
  var validLen = lens[0]
  var placeHoldersLen = lens[1]
  return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen
}

function _byteLength (b64, validLen, placeHoldersLen) {
  return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen
}

function toByteArray (b64) {
  var tmp
  var lens = getLens(b64)
  var validLen = lens[0]
  var placeHoldersLen = lens[1]

  var arr = new Arr(_byteLength(b64, validLen, placeHoldersLen))

  var curByte = 0

  // if there are placeholders, only get up to the last complete 4 chars
  var len = placeHoldersLen > 0
    ? validLen - 4
    : validLen

  for (var i = 0; i < len; i += 4) {
    tmp =
      (revLookup[b64.charCodeAt(i)] << 18) |
      (revLookup[b64.charCodeAt(i + 1)] << 12) |
      (revLookup[b64.charCodeAt(i + 2)] << 6) |
      revLookup[b64.charCodeAt(i + 3)]
    arr[curByte++] = (tmp >> 16) & 0xFF
    arr[curByte++] = (tmp >> 8) & 0xFF
    arr[curByte++] = tmp & 0xFF
  }

  if (placeHoldersLen === 2) {
    tmp =
      (revLookup[b64.charCodeAt(i)] << 2) |
      (revLookup[b64.charCodeAt(i + 1)] >> 4)
    arr[curByte++] = tmp & 0xFF
  }

  if (placeHoldersLen === 1) {
    tmp =
      (revLookup[b64.charCodeAt(i)] << 10) |
      (revLookup[b64.charCodeAt(i + 1)] << 4) |
      (revLookup[b64.charCodeAt(i + 2)] >> 2)
    arr[curByte++] = (tmp >> 8) & 0xFF
    arr[curByte++] = tmp & 0xFF
  }

  return arr
}

function tripletToBase64 (num) {
  return lookup[num >> 18 & 0x3F] +
    lookup[num >> 12 & 0x3F] +
    lookup[num >> 6 & 0x3F] +
    lookup[num & 0x3F]
}

function encodeChunk (uint8, start, end) {
  var tmp
  var output = []
  for (var i = start; i < end; i += 3) {
    tmp =
      ((uint8[i] << 16) & 0xFF0000) +
      ((uint8[i + 1] << 8) & 0xFF00) +
      (uint8[i + 2] & 0xFF)
    output.push(tripletToBase64(tmp))
  }
  return output.join('')
}

function fromByteArray (uint8) {
  var tmp
  var len = uint8.length
  var extraBytes = len % 3 // if we have 1 byte left, pad 2 bytes
  var parts = []
  var maxChunkLength = 16383 // must be multiple of 3

  // go through the array every three bytes, we'll deal with trailing stuff later
  for (var i = 0, len2 = len - extraBytes; i < len2; i += maxChunkLength) {
    parts.push(encodeChunk(
      uint8, i, (i + maxChunkLength) > len2 ? len2 : (i + maxChunkLength)
    ))
  }

  // pad the end with zeros, but make sure to not forget the extra bytes
  if (extraBytes === 1) {
    tmp = uint8[len - 1]
    parts.push(
      lookup[tmp >> 2] +
      lookup[(tmp << 4) & 0x3F] +
      '=='
    )
  } else if (extraBytes === 2) {
    tmp = (uint8[len - 2] << 8) + uint8[len - 1]
    parts.push(
      lookup[tmp >> 10] +
      lookup[(tmp >> 4) & 0x3F] +
      lookup[(tmp << 2) & 0x3F] +
      '='
    )
  }

  return parts.join('')
}

},{}],21:[function(require,module,exports){

},{}],22:[function(require,module,exports){
(function (global){
/*! https://mths.be/punycode v1.4.1 by @mathias */
;(function(root) {

	/** Detect free variables */
	var freeExports = typeof exports == 'object' && exports &&
		!exports.nodeType && exports;
	var freeModule = typeof module == 'object' && module &&
		!module.nodeType && module;
	var freeGlobal = typeof global == 'object' && global;
	if (
		freeGlobal.global === freeGlobal ||
		freeGlobal.window === freeGlobal ||
		freeGlobal.self === freeGlobal
	) {
		root = freeGlobal;
	}

	/**
	 * The `punycode` object.
	 * @name punycode
	 * @type Object
	 */
	var punycode,

	/** Highest positive signed 32-bit float value */
	maxInt = 2147483647, // aka. 0x7FFFFFFF or 2^31-1

	/** Bootstring parameters */
	base = 36,
	tMin = 1,
	tMax = 26,
	skew = 38,
	damp = 700,
	initialBias = 72,
	initialN = 128, // 0x80
	delimiter = '-', // '\x2D'

	/** Regular expressions */
	regexPunycode = /^xn--/,
	regexNonASCII = /[^\x20-\x7E]/, // unprintable ASCII chars + non-ASCII chars
	regexSeparators = /[\x2E\u3002\uFF0E\uFF61]/g, // RFC 3490 separators

	/** Error messages */
	errors = {
		'overflow': 'Overflow: input needs wider integers to process',
		'not-basic': 'Illegal input >= 0x80 (not a basic code point)',
		'invalid-input': 'Invalid input'
	},

	/** Convenience shortcuts */
	baseMinusTMin = base - tMin,
	floor = Math.floor,
	stringFromCharCode = String.fromCharCode,

	/** Temporary variable */
	key;

	/*--------------------------------------------------------------------------*/

	/**
	 * A generic error utility function.
	 * @private
	 * @param {String} type The error type.
	 * @returns {Error} Throws a `RangeError` with the applicable error message.
	 */
	function error(type) {
		throw new RangeError(errors[type]);
	}

	/**
	 * A generic `Array#map` utility function.
	 * @private
	 * @param {Array} array The array to iterate over.
	 * @param {Function} callback The function that gets called for every array
	 * item.
	 * @returns {Array} A new array of values returned by the callback function.
	 */
	function map(array, fn) {
		var length = array.length;
		var result = [];
		while (length--) {
			result[length] = fn(array[length]);
		}
		return result;
	}

	/**
	 * A simple `Array#map`-like wrapper to work with domain name strings or email
	 * addresses.
	 * @private
	 * @param {String} domain The domain name or email address.
	 * @param {Function} callback The function that gets called for every
	 * character.
	 * @returns {Array} A new string of characters returned by the callback
	 * function.
	 */
	function mapDomain(string, fn) {
		var parts = string.split('@');
		var result = '';
		if (parts.length > 1) {
			// In email addresses, only the domain name should be punycoded. Leave
			// the local part (i.e. everything up to `@`) intact.
			result = parts[0] + '@';
			string = parts[1];
		}
		// Avoid `split(regex)` for IE8 compatibility. See #17.
		string = string.replace(regexSeparators, '\x2E');
		var labels = string.split('.');
		var encoded = map(labels, fn).join('.');
		return result + encoded;
	}

	/**
	 * Creates an array containing the numeric code points of each Unicode
	 * character in the string. While JavaScript uses UCS-2 internally,
	 * this function will convert a pair of surrogate halves (each of which
	 * UCS-2 exposes as separate characters) into a single code point,
	 * matching UTF-16.
	 * @see `punycode.ucs2.encode`
	 * @see <https://mathiasbynens.be/notes/javascript-encoding>
	 * @memberOf punycode.ucs2
	 * @name decode
	 * @param {String} string The Unicode input string (UCS-2).
	 * @returns {Array} The new array of code points.
	 */
	function ucs2decode(string) {
		var output = [],
		    counter = 0,
		    length = string.length,
		    value,
		    extra;
		while (counter < length) {
			value = string.charCodeAt(counter++);
			if (value >= 0xD800 && value <= 0xDBFF && counter < length) {
				// high surrogate, and there is a next character
				extra = string.charCodeAt(counter++);
				if ((extra & 0xFC00) == 0xDC00) { // low surrogate
					output.push(((value & 0x3FF) << 10) + (extra & 0x3FF) + 0x10000);
				} else {
					// unmatched surrogate; only append this code unit, in case the next
					// code unit is the high surrogate of a surrogate pair
					output.push(value);
					counter--;
				}
			} else {
				output.push(value);
			}
		}
		return output;
	}

	/**
	 * Creates a string based on an array of numeric code points.
	 * @see `punycode.ucs2.decode`
	 * @memberOf punycode.ucs2
	 * @name encode
	 * @param {Array} codePoints The array of numeric code points.
	 * @returns {String} The new Unicode string (UCS-2).
	 */
	function ucs2encode(array) {
		return map(array, function(value) {
			var output = '';
			if (value > 0xFFFF) {
				value -= 0x10000;
				output += stringFromCharCode(value >>> 10 & 0x3FF | 0xD800);
				value = 0xDC00 | value & 0x3FF;
			}
			output += stringFromCharCode(value);
			return output;
		}).join('');
	}

	/**
	 * Converts a basic code point into a digit/integer.
	 * @see `digitToBasic()`
	 * @private
	 * @param {Number} codePoint The basic numeric code point value.
	 * @returns {Number} The numeric value of a basic code point (for use in
	 * representing integers) in the range `0` to `base - 1`, or `base` if
	 * the code point does not represent a value.
	 */
	function basicToDigit(codePoint) {
		if (codePoint - 48 < 10) {
			return codePoint - 22;
		}
		if (codePoint - 65 < 26) {
			return codePoint - 65;
		}
		if (codePoint - 97 < 26) {
			return codePoint - 97;
		}
		return base;
	}

	/**
	 * Converts a digit/integer into a basic code point.
	 * @see `basicToDigit()`
	 * @private
	 * @param {Number} digit The numeric value of a basic code point.
	 * @returns {Number} The basic code point whose value (when used for
	 * representing integers) is `digit`, which needs to be in the range
	 * `0` to `base - 1`. If `flag` is non-zero, the uppercase form is
	 * used; else, the lowercase form is used. The behavior is undefined
	 * if `flag` is non-zero and `digit` has no uppercase form.
	 */
	function digitToBasic(digit, flag) {
		//  0..25 map to ASCII a..z or A..Z
		// 26..35 map to ASCII 0..9
		return digit + 22 + 75 * (digit < 26) - ((flag != 0) << 5);
	}

	/**
	 * Bias adaptation function as per section 3.4 of RFC 3492.
	 * https://tools.ietf.org/html/rfc3492#section-3.4
	 * @private
	 */
	function adapt(delta, numPoints, firstTime) {
		var k = 0;
		delta = firstTime ? floor(delta / damp) : delta >> 1;
		delta += floor(delta / numPoints);
		for (/* no initialization */; delta > baseMinusTMin * tMax >> 1; k += base) {
			delta = floor(delta / baseMinusTMin);
		}
		return floor(k + (baseMinusTMin + 1) * delta / (delta + skew));
	}

	/**
	 * Converts a Punycode string of ASCII-only symbols to a string of Unicode
	 * symbols.
	 * @memberOf punycode
	 * @param {String} input The Punycode string of ASCII-only symbols.
	 * @returns {String} The resulting string of Unicode symbols.
	 */
	function decode(input) {
		// Don't use UCS-2
		var output = [],
		    inputLength = input.length,
		    out,
		    i = 0,
		    n = initialN,
		    bias = initialBias,
		    basic,
		    j,
		    index,
		    oldi,
		    w,
		    k,
		    digit,
		    t,
		    /** Cached calculation results */
		    baseMinusT;

		// Handle the basic code points: let `basic` be the number of input code
		// points before the last delimiter, or `0` if there is none, then copy
		// the first basic code points to the output.

		basic = input.lastIndexOf(delimiter);
		if (basic < 0) {
			basic = 0;
		}

		for (j = 0; j < basic; ++j) {
			// if it's not a basic code point
			if (input.charCodeAt(j) >= 0x80) {
				error('not-basic');
			}
			output.push(input.charCodeAt(j));
		}

		// Main decoding loop: start just after the last delimiter if any basic code
		// points were copied; start at the beginning otherwise.

		for (index = basic > 0 ? basic + 1 : 0; index < inputLength; /* no final expression */) {

			// `index` is the index of the next character to be consumed.
			// Decode a generalized variable-length integer into `delta`,
			// which gets added to `i`. The overflow checking is easier
			// if we increase `i` as we go, then subtract off its starting
			// value at the end to obtain `delta`.
			for (oldi = i, w = 1, k = base; /* no condition */; k += base) {

				if (index >= inputLength) {
					error('invalid-input');
				}

				digit = basicToDigit(input.charCodeAt(index++));

				if (digit >= base || digit > floor((maxInt - i) / w)) {
					error('overflow');
				}

				i += digit * w;
				t = k <= bias ? tMin : (k >= bias + tMax ? tMax : k - bias);

				if (digit < t) {
					break;
				}

				baseMinusT = base - t;
				if (w > floor(maxInt / baseMinusT)) {
					error('overflow');
				}

				w *= baseMinusT;

			}

			out = output.length + 1;
			bias = adapt(i - oldi, out, oldi == 0);

			// `i` was supposed to wrap around from `out` to `0`,
			// incrementing `n` each time, so we'll fix that now:
			if (floor(i / out) > maxInt - n) {
				error('overflow');
			}

			n += floor(i / out);
			i %= out;

			// Insert `n` at position `i` of the output
			output.splice(i++, 0, n);

		}

		return ucs2encode(output);
	}

	/**
	 * Converts a string of Unicode symbols (e.g. a domain name label) to a
	 * Punycode string of ASCII-only symbols.
	 * @memberOf punycode
	 * @param {String} input The string of Unicode symbols.
	 * @returns {String} The resulting Punycode string of ASCII-only symbols.
	 */
	function encode(input) {
		var n,
		    delta,
		    handledCPCount,
		    basicLength,
		    bias,
		    j,
		    m,
		    q,
		    k,
		    t,
		    currentValue,
		    output = [],
		    /** `inputLength` will hold the number of code points in `input`. */
		    inputLength,
		    /** Cached calculation results */
		    handledCPCountPlusOne,
		    baseMinusT,
		    qMinusT;

		// Convert the input in UCS-2 to Unicode
		input = ucs2decode(input);

		// Cache the length
		inputLength = input.length;

		// Initialize the state
		n = initialN;
		delta = 0;
		bias = initialBias;

		// Handle the basic code points
		for (j = 0; j < inputLength; ++j) {
			currentValue = input[j];
			if (currentValue < 0x80) {
				output.push(stringFromCharCode(currentValue));
			}
		}

		handledCPCount = basicLength = output.length;

		// `handledCPCount` is the number of code points that have been handled;
		// `basicLength` is the number of basic code points.

		// Finish the basic string - if it is not empty - with a delimiter
		if (basicLength) {
			output.push(delimiter);
		}

		// Main encoding loop:
		while (handledCPCount < inputLength) {

			// All non-basic code points < n have been handled already. Find the next
			// larger one:
			for (m = maxInt, j = 0; j < inputLength; ++j) {
				currentValue = input[j];
				if (currentValue >= n && currentValue < m) {
					m = currentValue;
				}
			}

			// Increase `delta` enough to advance the decoder's <n,i> state to <m,0>,
			// but guard against overflow
			handledCPCountPlusOne = handledCPCount + 1;
			if (m - n > floor((maxInt - delta) / handledCPCountPlusOne)) {
				error('overflow');
			}

			delta += (m - n) * handledCPCountPlusOne;
			n = m;

			for (j = 0; j < inputLength; ++j) {
				currentValue = input[j];

				if (currentValue < n && ++delta > maxInt) {
					error('overflow');
				}

				if (currentValue == n) {
					// Represent delta as a generalized variable-length integer
					for (q = delta, k = base; /* no condition */; k += base) {
						t = k <= bias ? tMin : (k >= bias + tMax ? tMax : k - bias);
						if (q < t) {
							break;
						}
						qMinusT = q - t;
						baseMinusT = base - t;
						output.push(
							stringFromCharCode(digitToBasic(t + qMinusT % baseMinusT, 0))
						);
						q = floor(qMinusT / baseMinusT);
					}

					output.push(stringFromCharCode(digitToBasic(q, 0)));
					bias = adapt(delta, handledCPCountPlusOne, handledCPCount == basicLength);
					delta = 0;
					++handledCPCount;
				}
			}

			++delta;
			++n;

		}
		return output.join('');
	}

	/**
	 * Converts a Punycode string representing a domain name or an email address
	 * to Unicode. Only the Punycoded parts of the input will be converted, i.e.
	 * it doesn't matter if you call it on a string that has already been
	 * converted to Unicode.
	 * @memberOf punycode
	 * @param {String} input The Punycoded domain name or email address to
	 * convert to Unicode.
	 * @returns {String} The Unicode representation of the given Punycode
	 * string.
	 */
	function toUnicode(input) {
		return mapDomain(input, function(string) {
			return regexPunycode.test(string)
				? decode(string.slice(4).toLowerCase())
				: string;
		});
	}

	/**
	 * Converts a Unicode string representing a domain name or an email address to
	 * Punycode. Only the non-ASCII parts of the domain name will be converted,
	 * i.e. it doesn't matter if you call it with a domain that's already in
	 * ASCII.
	 * @memberOf punycode
	 * @param {String} input The domain name or email address to convert, as a
	 * Unicode string.
	 * @returns {String} The Punycode representation of the given domain name or
	 * email address.
	 */
	function toASCII(input) {
		return mapDomain(input, function(string) {
			return regexNonASCII.test(string)
				? 'xn--' + encode(string)
				: string;
		});
	}

	/*--------------------------------------------------------------------------*/

	/** Define the public API */
	punycode = {
		/**
		 * A string representing the current Punycode.js version number.
		 * @memberOf punycode
		 * @type String
		 */
		'version': '1.4.1',
		/**
		 * An object of methods to convert from JavaScript's internal character
		 * representation (UCS-2) to Unicode code points, and back.
		 * @see <https://mathiasbynens.be/notes/javascript-encoding>
		 * @memberOf punycode
		 * @type Object
		 */
		'ucs2': {
			'decode': ucs2decode,
			'encode': ucs2encode
		},
		'decode': decode,
		'encode': encode,
		'toASCII': toASCII,
		'toUnicode': toUnicode
	};

	/** Expose `punycode` */
	// Some AMD build optimizers, like r.js, check for specific condition patterns
	// like the following:
	if (
		typeof define == 'function' &&
		typeof define.amd == 'object' &&
		define.amd
	) {
		define('punycode', function() {
			return punycode;
		});
	} else if (freeExports && freeModule) {
		if (module.exports == freeExports) {
			// in Node.js, io.js, or RingoJS v0.8.0+
			freeModule.exports = punycode;
		} else {
			// in Narwhal or RingoJS v0.7.0-
			for (key in punycode) {
				punycode.hasOwnProperty(key) && (freeExports[key] = punycode[key]);
			}
		}
	} else {
		// in Rhino or a web browser
		root.punycode = punycode;
	}

}(this));

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{}],23:[function(require,module,exports){
/*!
 * The buffer module from node.js, for the browser.
 *
 * @author   Feross Aboukhadijeh <https://feross.org>
 * @license  MIT
 */
/* eslint-disable no-proto */

'use strict'

var base64 = require('base64-js')
var ieee754 = require('ieee754')

exports.Buffer = Buffer
exports.SlowBuffer = SlowBuffer
exports.INSPECT_MAX_BYTES = 50

var K_MAX_LENGTH = 0x7fffffff
exports.kMaxLength = K_MAX_LENGTH

/**
 * If `Buffer.TYPED_ARRAY_SUPPORT`:
 *   === true    Use Uint8Array implementation (fastest)
 *   === false   Print warning and recommend using `buffer` v4.x which has an Object
 *               implementation (most compatible, even IE6)
 *
 * Browsers that support typed arrays are IE 10+, Firefox 4+, Chrome 7+, Safari 5.1+,
 * Opera 11.6+, iOS 4.2+.
 *
 * We report that the browser does not support typed arrays if the are not subclassable
 * using __proto__. Firefox 4-29 lacks support for adding new properties to `Uint8Array`
 * (See: https://bugzilla.mozilla.org/show_bug.cgi?id=695438). IE 10 lacks support
 * for __proto__ and has a buggy typed array implementation.
 */
Buffer.TYPED_ARRAY_SUPPORT = typedArraySupport()

if (!Buffer.TYPED_ARRAY_SUPPORT && typeof console !== 'undefined' &&
    typeof console.error === 'function') {
  console.error(
    'This browser lacks typed array (Uint8Array) support which is required by ' +
    '`buffer` v5.x. Use `buffer` v4.x if you require old browser support.'
  )
}

function typedArraySupport () {
  // Can typed array instances can be augmented?
  try {
    var arr = new Uint8Array(1)
    arr.__proto__ = { __proto__: Uint8Array.prototype, foo: function () { return 42 } }
    return arr.foo() === 42
  } catch (e) {
    return false
  }
}

Object.defineProperty(Buffer.prototype, 'parent', {
  enumerable: true,
  get: function () {
    if (!Buffer.isBuffer(this)) return undefined
    return this.buffer
  }
})

Object.defineProperty(Buffer.prototype, 'offset', {
  enumerable: true,
  get: function () {
    if (!Buffer.isBuffer(this)) return undefined
    return this.byteOffset
  }
})

function createBuffer (length) {
  if (length > K_MAX_LENGTH) {
    throw new RangeError('The value "' + length + '" is invalid for option "size"')
  }
  // Return an augmented `Uint8Array` instance
  var buf = new Uint8Array(length)
  buf.__proto__ = Buffer.prototype
  return buf
}

/**
 * The Buffer constructor returns instances of `Uint8Array` that have their
 * prototype changed to `Buffer.prototype`. Furthermore, `Buffer` is a subclass of
 * `Uint8Array`, so the returned instances will have all the node `Buffer` methods
 * and the `Uint8Array` methods. Square bracket notation works as expected -- it
 * returns a single octet.
 *
 * The `Uint8Array` prototype remains unmodified.
 */

function Buffer (arg, encodingOrOffset, length) {
  // Common case.
  if (typeof arg === 'number') {
    if (typeof encodingOrOffset === 'string') {
      throw new TypeError(
        'The "string" argument must be of type string. Received type number'
      )
    }
    return allocUnsafe(arg)
  }
  return from(arg, encodingOrOffset, length)
}

// Fix subarray() in ES2016. See: https://github.com/feross/buffer/pull/97
if (typeof Symbol !== 'undefined' && Symbol.species != null &&
    Buffer[Symbol.species] === Buffer) {
  Object.defineProperty(Buffer, Symbol.species, {
    value: null,
    configurable: true,
    enumerable: false,
    writable: false
  })
}

Buffer.poolSize = 8192 // not used by this implementation

function from (value, encodingOrOffset, length) {
  if (typeof value === 'string') {
    return fromString(value, encodingOrOffset)
  }

  if (ArrayBuffer.isView(value)) {
    return fromArrayLike(value)
  }

  if (value == null) {
    throw TypeError(
      'The first argument must be one of type string, Buffer, ArrayBuffer, Array, ' +
      'or Array-like Object. Received type ' + (typeof value)
    )
  }

  if (isInstance(value, ArrayBuffer) ||
      (value && isInstance(value.buffer, ArrayBuffer))) {
    return fromArrayBuffer(value, encodingOrOffset, length)
  }

  if (typeof value === 'number') {
    throw new TypeError(
      'The "value" argument must not be of type number. Received type number'
    )
  }

  var valueOf = value.valueOf && value.valueOf()
  if (valueOf != null && valueOf !== value) {
    return Buffer.from(valueOf, encodingOrOffset, length)
  }

  var b = fromObject(value)
  if (b) return b

  if (typeof Symbol !== 'undefined' && Symbol.toPrimitive != null &&
      typeof value[Symbol.toPrimitive] === 'function') {
    return Buffer.from(
      value[Symbol.toPrimitive]('string'), encodingOrOffset, length
    )
  }

  throw new TypeError(
    'The first argument must be one of type string, Buffer, ArrayBuffer, Array, ' +
    'or Array-like Object. Received type ' + (typeof value)
  )
}

/**
 * Functionally equivalent to Buffer(arg, encoding) but throws a TypeError
 * if value is a number.
 * Buffer.from(str[, encoding])
 * Buffer.from(array)
 * Buffer.from(buffer)
 * Buffer.from(arrayBuffer[, byteOffset[, length]])
 **/
Buffer.from = function (value, encodingOrOffset, length) {
  return from(value, encodingOrOffset, length)
}

// Note: Change prototype *after* Buffer.from is defined to workaround Chrome bug:
// https://github.com/feross/buffer/pull/148
Buffer.prototype.__proto__ = Uint8Array.prototype
Buffer.__proto__ = Uint8Array

function assertSize (size) {
  if (typeof size !== 'number') {
    throw new TypeError('"size" argument must be of type number')
  } else if (size < 0) {
    throw new RangeError('The value "' + size + '" is invalid for option "size"')
  }
}

function alloc (size, fill, encoding) {
  assertSize(size)
  if (size <= 0) {
    return createBuffer(size)
  }
  if (fill !== undefined) {
    // Only pay attention to encoding if it's a string. This
    // prevents accidentally sending in a number that would
    // be interpretted as a start offset.
    return typeof encoding === 'string'
      ? createBuffer(size).fill(fill, encoding)
      : createBuffer(size).fill(fill)
  }
  return createBuffer(size)
}

/**
 * Creates a new filled Buffer instance.
 * alloc(size[, fill[, encoding]])
 **/
Buffer.alloc = function (size, fill, encoding) {
  return alloc(size, fill, encoding)
}

function allocUnsafe (size) {
  assertSize(size)
  return createBuffer(size < 0 ? 0 : checked(size) | 0)
}

/**
 * Equivalent to Buffer(num), by default creates a non-zero-filled Buffer instance.
 * */
Buffer.allocUnsafe = function (size) {
  return allocUnsafe(size)
}
/**
 * Equivalent to SlowBuffer(num), by default creates a non-zero-filled Buffer instance.
 */
Buffer.allocUnsafeSlow = function (size) {
  return allocUnsafe(size)
}

function fromString (string, encoding) {
  if (typeof encoding !== 'string' || encoding === '') {
    encoding = 'utf8'
  }

  if (!Buffer.isEncoding(encoding)) {
    throw new TypeError('Unknown encoding: ' + encoding)
  }

  var length = byteLength(string, encoding) | 0
  var buf = createBuffer(length)

  var actual = buf.write(string, encoding)

  if (actual !== length) {
    // Writing a hex string, for example, that contains invalid characters will
    // cause everything after the first invalid character to be ignored. (e.g.
    // 'abxxcd' will be treated as 'ab')
    buf = buf.slice(0, actual)
  }

  return buf
}

function fromArrayLike (array) {
  var length = array.length < 0 ? 0 : checked(array.length) | 0
  var buf = createBuffer(length)
  for (var i = 0; i < length; i += 1) {
    buf[i] = array[i] & 255
  }
  return buf
}

function fromArrayBuffer (array, byteOffset, length) {
  if (byteOffset < 0 || array.byteLength < byteOffset) {
    throw new RangeError('"offset" is outside of buffer bounds')
  }

  if (array.byteLength < byteOffset + (length || 0)) {
    throw new RangeError('"length" is outside of buffer bounds')
  }

  var buf
  if (byteOffset === undefined && length === undefined) {
    buf = new Uint8Array(array)
  } else if (length === undefined) {
    buf = new Uint8Array(array, byteOffset)
  } else {
    buf = new Uint8Array(array, byteOffset, length)
  }

  // Return an augmented `Uint8Array` instance
  buf.__proto__ = Buffer.prototype
  return buf
}

function fromObject (obj) {
  if (Buffer.isBuffer(obj)) {
    var len = checked(obj.length) | 0
    var buf = createBuffer(len)

    if (buf.length === 0) {
      return buf
    }

    obj.copy(buf, 0, 0, len)
    return buf
  }

  if (obj.length !== undefined) {
    if (typeof obj.length !== 'number' || numberIsNaN(obj.length)) {
      return createBuffer(0)
    }
    return fromArrayLike(obj)
  }

  if (obj.type === 'Buffer' && Array.isArray(obj.data)) {
    return fromArrayLike(obj.data)
  }
}

function checked (length) {
  // Note: cannot use `length < K_MAX_LENGTH` here because that fails when
  // length is NaN (which is otherwise coerced to zero.)
  if (length >= K_MAX_LENGTH) {
    throw new RangeError('Attempt to allocate Buffer larger than maximum ' +
                         'size: 0x' + K_MAX_LENGTH.toString(16) + ' bytes')
  }
  return length | 0
}

function SlowBuffer (length) {
  if (+length != length) { // eslint-disable-line eqeqeq
    length = 0
  }
  return Buffer.alloc(+length)
}

Buffer.isBuffer = function isBuffer (b) {
  return b != null && b._isBuffer === true &&
    b !== Buffer.prototype // so Buffer.isBuffer(Buffer.prototype) will be false
}

Buffer.compare = function compare (a, b) {
  if (isInstance(a, Uint8Array)) a = Buffer.from(a, a.offset, a.byteLength)
  if (isInstance(b, Uint8Array)) b = Buffer.from(b, b.offset, b.byteLength)
  if (!Buffer.isBuffer(a) || !Buffer.isBuffer(b)) {
    throw new TypeError(
      'The "buf1", "buf2" arguments must be one of type Buffer or Uint8Array'
    )
  }

  if (a === b) return 0

  var x = a.length
  var y = b.length

  for (var i = 0, len = Math.min(x, y); i < len; ++i) {
    if (a[i] !== b[i]) {
      x = a[i]
      y = b[i]
      break
    }
  }

  if (x < y) return -1
  if (y < x) return 1
  return 0
}

Buffer.isEncoding = function isEncoding (encoding) {
  switch (String(encoding).toLowerCase()) {
    case 'hex':
    case 'utf8':
    case 'utf-8':
    case 'ascii':
    case 'latin1':
    case 'binary':
    case 'base64':
    case 'ucs2':
    case 'ucs-2':
    case 'utf16le':
    case 'utf-16le':
      return true
    default:
      return false
  }
}

Buffer.concat = function concat (list, length) {
  if (!Array.isArray(list)) {
    throw new TypeError('"list" argument must be an Array of Buffers')
  }

  if (list.length === 0) {
    return Buffer.alloc(0)
  }

  var i
  if (length === undefined) {
    length = 0
    for (i = 0; i < list.length; ++i) {
      length += list[i].length
    }
  }

  var buffer = Buffer.allocUnsafe(length)
  var pos = 0
  for (i = 0; i < list.length; ++i) {
    var buf = list[i]
    if (isInstance(buf, Uint8Array)) {
      buf = Buffer.from(buf)
    }
    if (!Buffer.isBuffer(buf)) {
      throw new TypeError('"list" argument must be an Array of Buffers')
    }
    buf.copy(buffer, pos)
    pos += buf.length
  }
  return buffer
}

function byteLength (string, encoding) {
  if (Buffer.isBuffer(string)) {
    return string.length
  }
  if (ArrayBuffer.isView(string) || isInstance(string, ArrayBuffer)) {
    return string.byteLength
  }
  if (typeof string !== 'string') {
    throw new TypeError(
      'The "string" argument must be one of type string, Buffer, or ArrayBuffer. ' +
      'Received type ' + typeof string
    )
  }

  var len = string.length
  var mustMatch = (arguments.length > 2 && arguments[2] === true)
  if (!mustMatch && len === 0) return 0

  // Use a for loop to avoid recursion
  var loweredCase = false
  for (;;) {
    switch (encoding) {
      case 'ascii':
      case 'latin1':
      case 'binary':
        return len
      case 'utf8':
      case 'utf-8':
        return utf8ToBytes(string).length
      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return len * 2
      case 'hex':
        return len >>> 1
      case 'base64':
        return base64ToBytes(string).length
      default:
        if (loweredCase) {
          return mustMatch ? -1 : utf8ToBytes(string).length // assume utf8
        }
        encoding = ('' + encoding).toLowerCase()
        loweredCase = true
    }
  }
}
Buffer.byteLength = byteLength

function slowToString (encoding, start, end) {
  var loweredCase = false

  // No need to verify that "this.length <= MAX_UINT32" since it's a read-only
  // property of a typed array.

  // This behaves neither like String nor Uint8Array in that we set start/end
  // to their upper/lower bounds if the value passed is out of range.
  // undefined is handled specially as per ECMA-262 6th Edition,
  // Section 13.3.3.7 Runtime Semantics: KeyedBindingInitialization.
  if (start === undefined || start < 0) {
    start = 0
  }
  // Return early if start > this.length. Done here to prevent potential uint32
  // coercion fail below.
  if (start > this.length) {
    return ''
  }

  if (end === undefined || end > this.length) {
    end = this.length
  }

  if (end <= 0) {
    return ''
  }

  // Force coersion to uint32. This will also coerce falsey/NaN values to 0.
  end >>>= 0
  start >>>= 0

  if (end <= start) {
    return ''
  }

  if (!encoding) encoding = 'utf8'

  while (true) {
    switch (encoding) {
      case 'hex':
        return hexSlice(this, start, end)

      case 'utf8':
      case 'utf-8':
        return utf8Slice(this, start, end)

      case 'ascii':
        return asciiSlice(this, start, end)

      case 'latin1':
      case 'binary':
        return latin1Slice(this, start, end)

      case 'base64':
        return base64Slice(this, start, end)

      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return utf16leSlice(this, start, end)

      default:
        if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
        encoding = (encoding + '').toLowerCase()
        loweredCase = true
    }
  }
}

// This property is used by `Buffer.isBuffer` (and the `is-buffer` npm package)
// to detect a Buffer instance. It's not possible to use `instanceof Buffer`
// reliably in a browserify context because there could be multiple different
// copies of the 'buffer' package in use. This method works even for Buffer
// instances that were created from another copy of the `buffer` package.
// See: https://github.com/feross/buffer/issues/154
Buffer.prototype._isBuffer = true

function swap (b, n, m) {
  var i = b[n]
  b[n] = b[m]
  b[m] = i
}

Buffer.prototype.swap16 = function swap16 () {
  var len = this.length
  if (len % 2 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 16-bits')
  }
  for (var i = 0; i < len; i += 2) {
    swap(this, i, i + 1)
  }
  return this
}

Buffer.prototype.swap32 = function swap32 () {
  var len = this.length
  if (len % 4 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 32-bits')
  }
  for (var i = 0; i < len; i += 4) {
    swap(this, i, i + 3)
    swap(this, i + 1, i + 2)
  }
  return this
}

Buffer.prototype.swap64 = function swap64 () {
  var len = this.length
  if (len % 8 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 64-bits')
  }
  for (var i = 0; i < len; i += 8) {
    swap(this, i, i + 7)
    swap(this, i + 1, i + 6)
    swap(this, i + 2, i + 5)
    swap(this, i + 3, i + 4)
  }
  return this
}

Buffer.prototype.toString = function toString () {
  var length = this.length
  if (length === 0) return ''
  if (arguments.length === 0) return utf8Slice(this, 0, length)
  return slowToString.apply(this, arguments)
}

Buffer.prototype.toLocaleString = Buffer.prototype.toString

Buffer.prototype.equals = function equals (b) {
  if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer')
  if (this === b) return true
  return Buffer.compare(this, b) === 0
}

Buffer.prototype.inspect = function inspect () {
  var str = ''
  var max = exports.INSPECT_MAX_BYTES
  str = this.toString('hex', 0, max).replace(/(.{2})/g, '$1 ').trim()
  if (this.length > max) str += ' ... '
  return '<Buffer ' + str + '>'
}

Buffer.prototype.compare = function compare (target, start, end, thisStart, thisEnd) {
  if (isInstance(target, Uint8Array)) {
    target = Buffer.from(target, target.offset, target.byteLength)
  }
  if (!Buffer.isBuffer(target)) {
    throw new TypeError(
      'The "target" argument must be one of type Buffer or Uint8Array. ' +
      'Received type ' + (typeof target)
    )
  }

  if (start === undefined) {
    start = 0
  }
  if (end === undefined) {
    end = target ? target.length : 0
  }
  if (thisStart === undefined) {
    thisStart = 0
  }
  if (thisEnd === undefined) {
    thisEnd = this.length
  }

  if (start < 0 || end > target.length || thisStart < 0 || thisEnd > this.length) {
    throw new RangeError('out of range index')
  }

  if (thisStart >= thisEnd && start >= end) {
    return 0
  }
  if (thisStart >= thisEnd) {
    return -1
  }
  if (start >= end) {
    return 1
  }

  start >>>= 0
  end >>>= 0
  thisStart >>>= 0
  thisEnd >>>= 0

  if (this === target) return 0

  var x = thisEnd - thisStart
  var y = end - start
  var len = Math.min(x, y)

  var thisCopy = this.slice(thisStart, thisEnd)
  var targetCopy = target.slice(start, end)

  for (var i = 0; i < len; ++i) {
    if (thisCopy[i] !== targetCopy[i]) {
      x = thisCopy[i]
      y = targetCopy[i]
      break
    }
  }

  if (x < y) return -1
  if (y < x) return 1
  return 0
}

// Finds either the first index of `val` in `buffer` at offset >= `byteOffset`,
// OR the last index of `val` in `buffer` at offset <= `byteOffset`.
//
// Arguments:
// - buffer - a Buffer to search
// - val - a string, Buffer, or number
// - byteOffset - an index into `buffer`; will be clamped to an int32
// - encoding - an optional encoding, relevant is val is a string
// - dir - true for indexOf, false for lastIndexOf
function bidirectionalIndexOf (buffer, val, byteOffset, encoding, dir) {
  // Empty buffer means no match
  if (buffer.length === 0) return -1

  // Normalize byteOffset
  if (typeof byteOffset === 'string') {
    encoding = byteOffset
    byteOffset = 0
  } else if (byteOffset > 0x7fffffff) {
    byteOffset = 0x7fffffff
  } else if (byteOffset < -0x80000000) {
    byteOffset = -0x80000000
  }
  byteOffset = +byteOffset // Coerce to Number.
  if (numberIsNaN(byteOffset)) {
    // byteOffset: it it's undefined, null, NaN, "foo", etc, search whole buffer
    byteOffset = dir ? 0 : (buffer.length - 1)
  }

  // Normalize byteOffset: negative offsets start from the end of the buffer
  if (byteOffset < 0) byteOffset = buffer.length + byteOffset
  if (byteOffset >= buffer.length) {
    if (dir) return -1
    else byteOffset = buffer.length - 1
  } else if (byteOffset < 0) {
    if (dir) byteOffset = 0
    else return -1
  }

  // Normalize val
  if (typeof val === 'string') {
    val = Buffer.from(val, encoding)
  }

  // Finally, search either indexOf (if dir is true) or lastIndexOf
  if (Buffer.isBuffer(val)) {
    // Special case: looking for empty string/buffer always fails
    if (val.length === 0) {
      return -1
    }
    return arrayIndexOf(buffer, val, byteOffset, encoding, dir)
  } else if (typeof val === 'number') {
    val = val & 0xFF // Search for a byte value [0-255]
    if (typeof Uint8Array.prototype.indexOf === 'function') {
      if (dir) {
        return Uint8Array.prototype.indexOf.call(buffer, val, byteOffset)
      } else {
        return Uint8Array.prototype.lastIndexOf.call(buffer, val, byteOffset)
      }
    }
    return arrayIndexOf(buffer, [ val ], byteOffset, encoding, dir)
  }

  throw new TypeError('val must be string, number or Buffer')
}

function arrayIndexOf (arr, val, byteOffset, encoding, dir) {
  var indexSize = 1
  var arrLength = arr.length
  var valLength = val.length

  if (encoding !== undefined) {
    encoding = String(encoding).toLowerCase()
    if (encoding === 'ucs2' || encoding === 'ucs-2' ||
        encoding === 'utf16le' || encoding === 'utf-16le') {
      if (arr.length < 2 || val.length < 2) {
        return -1
      }
      indexSize = 2
      arrLength /= 2
      valLength /= 2
      byteOffset /= 2
    }
  }

  function read (buf, i) {
    if (indexSize === 1) {
      return buf[i]
    } else {
      return buf.readUInt16BE(i * indexSize)
    }
  }

  var i
  if (dir) {
    var foundIndex = -1
    for (i = byteOffset; i < arrLength; i++) {
      if (read(arr, i) === read(val, foundIndex === -1 ? 0 : i - foundIndex)) {
        if (foundIndex === -1) foundIndex = i
        if (i - foundIndex + 1 === valLength) return foundIndex * indexSize
      } else {
        if (foundIndex !== -1) i -= i - foundIndex
        foundIndex = -1
      }
    }
  } else {
    if (byteOffset + valLength > arrLength) byteOffset = arrLength - valLength
    for (i = byteOffset; i >= 0; i--) {
      var found = true
      for (var j = 0; j < valLength; j++) {
        if (read(arr, i + j) !== read(val, j)) {
          found = false
          break
        }
      }
      if (found) return i
    }
  }

  return -1
}

Buffer.prototype.includes = function includes (val, byteOffset, encoding) {
  return this.indexOf(val, byteOffset, encoding) !== -1
}

Buffer.prototype.indexOf = function indexOf (val, byteOffset, encoding) {
  return bidirectionalIndexOf(this, val, byteOffset, encoding, true)
}

Buffer.prototype.lastIndexOf = function lastIndexOf (val, byteOffset, encoding) {
  return bidirectionalIndexOf(this, val, byteOffset, encoding, false)
}

function hexWrite (buf, string, offset, length) {
  offset = Number(offset) || 0
  var remaining = buf.length - offset
  if (!length) {
    length = remaining
  } else {
    length = Number(length)
    if (length > remaining) {
      length = remaining
    }
  }

  var strLen = string.length

  if (length > strLen / 2) {
    length = strLen / 2
  }
  for (var i = 0; i < length; ++i) {
    var parsed = parseInt(string.substr(i * 2, 2), 16)
    if (numberIsNaN(parsed)) return i
    buf[offset + i] = parsed
  }
  return i
}

function utf8Write (buf, string, offset, length) {
  return blitBuffer(utf8ToBytes(string, buf.length - offset), buf, offset, length)
}

function asciiWrite (buf, string, offset, length) {
  return blitBuffer(asciiToBytes(string), buf, offset, length)
}

function latin1Write (buf, string, offset, length) {
  return asciiWrite(buf, string, offset, length)
}

function base64Write (buf, string, offset, length) {
  return blitBuffer(base64ToBytes(string), buf, offset, length)
}

function ucs2Write (buf, string, offset, length) {
  return blitBuffer(utf16leToBytes(string, buf.length - offset), buf, offset, length)
}

Buffer.prototype.write = function write (string, offset, length, encoding) {
  // Buffer#write(string)
  if (offset === undefined) {
    encoding = 'utf8'
    length = this.length
    offset = 0
  // Buffer#write(string, encoding)
  } else if (length === undefined && typeof offset === 'string') {
    encoding = offset
    length = this.length
    offset = 0
  // Buffer#write(string, offset[, length][, encoding])
  } else if (isFinite(offset)) {
    offset = offset >>> 0
    if (isFinite(length)) {
      length = length >>> 0
      if (encoding === undefined) encoding = 'utf8'
    } else {
      encoding = length
      length = undefined
    }
  } else {
    throw new Error(
      'Buffer.write(string, encoding, offset[, length]) is no longer supported'
    )
  }

  var remaining = this.length - offset
  if (length === undefined || length > remaining) length = remaining

  if ((string.length > 0 && (length < 0 || offset < 0)) || offset > this.length) {
    throw new RangeError('Attempt to write outside buffer bounds')
  }

  if (!encoding) encoding = 'utf8'

  var loweredCase = false
  for (;;) {
    switch (encoding) {
      case 'hex':
        return hexWrite(this, string, offset, length)

      case 'utf8':
      case 'utf-8':
        return utf8Write(this, string, offset, length)

      case 'ascii':
        return asciiWrite(this, string, offset, length)

      case 'latin1':
      case 'binary':
        return latin1Write(this, string, offset, length)

      case 'base64':
        // Warning: maxLength not taken into account in base64Write
        return base64Write(this, string, offset, length)

      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return ucs2Write(this, string, offset, length)

      default:
        if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
        encoding = ('' + encoding).toLowerCase()
        loweredCase = true
    }
  }
}

Buffer.prototype.toJSON = function toJSON () {
  return {
    type: 'Buffer',
    data: Array.prototype.slice.call(this._arr || this, 0)
  }
}

function base64Slice (buf, start, end) {
  if (start === 0 && end === buf.length) {
    return base64.fromByteArray(buf)
  } else {
    return base64.fromByteArray(buf.slice(start, end))
  }
}

function utf8Slice (buf, start, end) {
  end = Math.min(buf.length, end)
  var res = []

  var i = start
  while (i < end) {
    var firstByte = buf[i]
    var codePoint = null
    var bytesPerSequence = (firstByte > 0xEF) ? 4
      : (firstByte > 0xDF) ? 3
        : (firstByte > 0xBF) ? 2
          : 1

    if (i + bytesPerSequence <= end) {
      var secondByte, thirdByte, fourthByte, tempCodePoint

      switch (bytesPerSequence) {
        case 1:
          if (firstByte < 0x80) {
            codePoint = firstByte
          }
          break
        case 2:
          secondByte = buf[i + 1]
          if ((secondByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0x1F) << 0x6 | (secondByte & 0x3F)
            if (tempCodePoint > 0x7F) {
              codePoint = tempCodePoint
            }
          }
          break
        case 3:
          secondByte = buf[i + 1]
          thirdByte = buf[i + 2]
          if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0xF) << 0xC | (secondByte & 0x3F) << 0x6 | (thirdByte & 0x3F)
            if (tempCodePoint > 0x7FF && (tempCodePoint < 0xD800 || tempCodePoint > 0xDFFF)) {
              codePoint = tempCodePoint
            }
          }
          break
        case 4:
          secondByte = buf[i + 1]
          thirdByte = buf[i + 2]
          fourthByte = buf[i + 3]
          if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80 && (fourthByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0xF) << 0x12 | (secondByte & 0x3F) << 0xC | (thirdByte & 0x3F) << 0x6 | (fourthByte & 0x3F)
            if (tempCodePoint > 0xFFFF && tempCodePoint < 0x110000) {
              codePoint = tempCodePoint
            }
          }
      }
    }

    if (codePoint === null) {
      // we did not generate a valid codePoint so insert a
      // replacement char (U+FFFD) and advance only 1 byte
      codePoint = 0xFFFD
      bytesPerSequence = 1
    } else if (codePoint > 0xFFFF) {
      // encode to utf16 (surrogate pair dance)
      codePoint -= 0x10000
      res.push(codePoint >>> 10 & 0x3FF | 0xD800)
      codePoint = 0xDC00 | codePoint & 0x3FF
    }

    res.push(codePoint)
    i += bytesPerSequence
  }

  return decodeCodePointsArray(res)
}

// Based on http://stackoverflow.com/a/22747272/680742, the browser with
// the lowest limit is Chrome, with 0x10000 args.
// We go 1 magnitude less, for safety
var MAX_ARGUMENTS_LENGTH = 0x1000

function decodeCodePointsArray (codePoints) {
  var len = codePoints.length
  if (len <= MAX_ARGUMENTS_LENGTH) {
    return String.fromCharCode.apply(String, codePoints) // avoid extra slice()
  }

  // Decode in chunks to avoid "call stack size exceeded".
  var res = ''
  var i = 0
  while (i < len) {
    res += String.fromCharCode.apply(
      String,
      codePoints.slice(i, i += MAX_ARGUMENTS_LENGTH)
    )
  }
  return res
}

function asciiSlice (buf, start, end) {
  var ret = ''
  end = Math.min(buf.length, end)

  for (var i = start; i < end; ++i) {
    ret += String.fromCharCode(buf[i] & 0x7F)
  }
  return ret
}

function latin1Slice (buf, start, end) {
  var ret = ''
  end = Math.min(buf.length, end)

  for (var i = start; i < end; ++i) {
    ret += String.fromCharCode(buf[i])
  }
  return ret
}

function hexSlice (buf, start, end) {
  var len = buf.length

  if (!start || start < 0) start = 0
  if (!end || end < 0 || end > len) end = len

  var out = ''
  for (var i = start; i < end; ++i) {
    out += toHex(buf[i])
  }
  return out
}

function utf16leSlice (buf, start, end) {
  var bytes = buf.slice(start, end)
  var res = ''
  for (var i = 0; i < bytes.length; i += 2) {
    res += String.fromCharCode(bytes[i] + (bytes[i + 1] * 256))
  }
  return res
}

Buffer.prototype.slice = function slice (start, end) {
  var len = this.length
  start = ~~start
  end = end === undefined ? len : ~~end

  if (start < 0) {
    start += len
    if (start < 0) start = 0
  } else if (start > len) {
    start = len
  }

  if (end < 0) {
    end += len
    if (end < 0) end = 0
  } else if (end > len) {
    end = len
  }

  if (end < start) end = start

  var newBuf = this.subarray(start, end)
  // Return an augmented `Uint8Array` instance
  newBuf.__proto__ = Buffer.prototype
  return newBuf
}

/*
 * Need to make sure that buffer isn't trying to write out of bounds.
 */
function checkOffset (offset, ext, length) {
  if ((offset % 1) !== 0 || offset < 0) throw new RangeError('offset is not uint')
  if (offset + ext > length) throw new RangeError('Trying to access beyond buffer length')
}

Buffer.prototype.readUIntLE = function readUIntLE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) checkOffset(offset, byteLength, this.length)

  var val = this[offset]
  var mul = 1
  var i = 0
  while (++i < byteLength && (mul *= 0x100)) {
    val += this[offset + i] * mul
  }

  return val
}

Buffer.prototype.readUIntBE = function readUIntBE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) {
    checkOffset(offset, byteLength, this.length)
  }

  var val = this[offset + --byteLength]
  var mul = 1
  while (byteLength > 0 && (mul *= 0x100)) {
    val += this[offset + --byteLength] * mul
  }

  return val
}

Buffer.prototype.readUInt8 = function readUInt8 (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 1, this.length)
  return this[offset]
}

Buffer.prototype.readUInt16LE = function readUInt16LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  return this[offset] | (this[offset + 1] << 8)
}

Buffer.prototype.readUInt16BE = function readUInt16BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  return (this[offset] << 8) | this[offset + 1]
}

Buffer.prototype.readUInt32LE = function readUInt32LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return ((this[offset]) |
      (this[offset + 1] << 8) |
      (this[offset + 2] << 16)) +
      (this[offset + 3] * 0x1000000)
}

Buffer.prototype.readUInt32BE = function readUInt32BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return (this[offset] * 0x1000000) +
    ((this[offset + 1] << 16) |
    (this[offset + 2] << 8) |
    this[offset + 3])
}

Buffer.prototype.readIntLE = function readIntLE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) checkOffset(offset, byteLength, this.length)

  var val = this[offset]
  var mul = 1
  var i = 0
  while (++i < byteLength && (mul *= 0x100)) {
    val += this[offset + i] * mul
  }
  mul *= 0x80

  if (val >= mul) val -= Math.pow(2, 8 * byteLength)

  return val
}

Buffer.prototype.readIntBE = function readIntBE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) checkOffset(offset, byteLength, this.length)

  var i = byteLength
  var mul = 1
  var val = this[offset + --i]
  while (i > 0 && (mul *= 0x100)) {
    val += this[offset + --i] * mul
  }
  mul *= 0x80

  if (val >= mul) val -= Math.pow(2, 8 * byteLength)

  return val
}

Buffer.prototype.readInt8 = function readInt8 (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 1, this.length)
  if (!(this[offset] & 0x80)) return (this[offset])
  return ((0xff - this[offset] + 1) * -1)
}

Buffer.prototype.readInt16LE = function readInt16LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  var val = this[offset] | (this[offset + 1] << 8)
  return (val & 0x8000) ? val | 0xFFFF0000 : val
}

Buffer.prototype.readInt16BE = function readInt16BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  var val = this[offset + 1] | (this[offset] << 8)
  return (val & 0x8000) ? val | 0xFFFF0000 : val
}

Buffer.prototype.readInt32LE = function readInt32LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return (this[offset]) |
    (this[offset + 1] << 8) |
    (this[offset + 2] << 16) |
    (this[offset + 3] << 24)
}

Buffer.prototype.readInt32BE = function readInt32BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return (this[offset] << 24) |
    (this[offset + 1] << 16) |
    (this[offset + 2] << 8) |
    (this[offset + 3])
}

Buffer.prototype.readFloatLE = function readFloatLE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)
  return ieee754.read(this, offset, true, 23, 4)
}

Buffer.prototype.readFloatBE = function readFloatBE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)
  return ieee754.read(this, offset, false, 23, 4)
}

Buffer.prototype.readDoubleLE = function readDoubleLE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 8, this.length)
  return ieee754.read(this, offset, true, 52, 8)
}

Buffer.prototype.readDoubleBE = function readDoubleBE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 8, this.length)
  return ieee754.read(this, offset, false, 52, 8)
}

function checkInt (buf, value, offset, ext, max, min) {
  if (!Buffer.isBuffer(buf)) throw new TypeError('"buffer" argument must be a Buffer instance')
  if (value > max || value < min) throw new RangeError('"value" argument is out of bounds')
  if (offset + ext > buf.length) throw new RangeError('Index out of range')
}

Buffer.prototype.writeUIntLE = function writeUIntLE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) {
    var maxBytes = Math.pow(2, 8 * byteLength) - 1
    checkInt(this, value, offset, byteLength, maxBytes, 0)
  }

  var mul = 1
  var i = 0
  this[offset] = value & 0xFF
  while (++i < byteLength && (mul *= 0x100)) {
    this[offset + i] = (value / mul) & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeUIntBE = function writeUIntBE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) {
    var maxBytes = Math.pow(2, 8 * byteLength) - 1
    checkInt(this, value, offset, byteLength, maxBytes, 0)
  }

  var i = byteLength - 1
  var mul = 1
  this[offset + i] = value & 0xFF
  while (--i >= 0 && (mul *= 0x100)) {
    this[offset + i] = (value / mul) & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeUInt8 = function writeUInt8 (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 1, 0xff, 0)
  this[offset] = (value & 0xff)
  return offset + 1
}

Buffer.prototype.writeUInt16LE = function writeUInt16LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0)
  this[offset] = (value & 0xff)
  this[offset + 1] = (value >>> 8)
  return offset + 2
}

Buffer.prototype.writeUInt16BE = function writeUInt16BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0)
  this[offset] = (value >>> 8)
  this[offset + 1] = (value & 0xff)
  return offset + 2
}

Buffer.prototype.writeUInt32LE = function writeUInt32LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0)
  this[offset + 3] = (value >>> 24)
  this[offset + 2] = (value >>> 16)
  this[offset + 1] = (value >>> 8)
  this[offset] = (value & 0xff)
  return offset + 4
}

Buffer.prototype.writeUInt32BE = function writeUInt32BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0)
  this[offset] = (value >>> 24)
  this[offset + 1] = (value >>> 16)
  this[offset + 2] = (value >>> 8)
  this[offset + 3] = (value & 0xff)
  return offset + 4
}

Buffer.prototype.writeIntLE = function writeIntLE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    var limit = Math.pow(2, (8 * byteLength) - 1)

    checkInt(this, value, offset, byteLength, limit - 1, -limit)
  }

  var i = 0
  var mul = 1
  var sub = 0
  this[offset] = value & 0xFF
  while (++i < byteLength && (mul *= 0x100)) {
    if (value < 0 && sub === 0 && this[offset + i - 1] !== 0) {
      sub = 1
    }
    this[offset + i] = ((value / mul) >> 0) - sub & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeIntBE = function writeIntBE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    var limit = Math.pow(2, (8 * byteLength) - 1)

    checkInt(this, value, offset, byteLength, limit - 1, -limit)
  }

  var i = byteLength - 1
  var mul = 1
  var sub = 0
  this[offset + i] = value & 0xFF
  while (--i >= 0 && (mul *= 0x100)) {
    if (value < 0 && sub === 0 && this[offset + i + 1] !== 0) {
      sub = 1
    }
    this[offset + i] = ((value / mul) >> 0) - sub & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeInt8 = function writeInt8 (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 1, 0x7f, -0x80)
  if (value < 0) value = 0xff + value + 1
  this[offset] = (value & 0xff)
  return offset + 1
}

Buffer.prototype.writeInt16LE = function writeInt16LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000)
  this[offset] = (value & 0xff)
  this[offset + 1] = (value >>> 8)
  return offset + 2
}

Buffer.prototype.writeInt16BE = function writeInt16BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000)
  this[offset] = (value >>> 8)
  this[offset + 1] = (value & 0xff)
  return offset + 2
}

Buffer.prototype.writeInt32LE = function writeInt32LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000)
  this[offset] = (value & 0xff)
  this[offset + 1] = (value >>> 8)
  this[offset + 2] = (value >>> 16)
  this[offset + 3] = (value >>> 24)
  return offset + 4
}

Buffer.prototype.writeInt32BE = function writeInt32BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000)
  if (value < 0) value = 0xffffffff + value + 1
  this[offset] = (value >>> 24)
  this[offset + 1] = (value >>> 16)
  this[offset + 2] = (value >>> 8)
  this[offset + 3] = (value & 0xff)
  return offset + 4
}

function checkIEEE754 (buf, value, offset, ext, max, min) {
  if (offset + ext > buf.length) throw new RangeError('Index out of range')
  if (offset < 0) throw new RangeError('Index out of range')
}

function writeFloat (buf, value, offset, littleEndian, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    checkIEEE754(buf, value, offset, 4, 3.4028234663852886e+38, -3.4028234663852886e+38)
  }
  ieee754.write(buf, value, offset, littleEndian, 23, 4)
  return offset + 4
}

Buffer.prototype.writeFloatLE = function writeFloatLE (value, offset, noAssert) {
  return writeFloat(this, value, offset, true, noAssert)
}

Buffer.prototype.writeFloatBE = function writeFloatBE (value, offset, noAssert) {
  return writeFloat(this, value, offset, false, noAssert)
}

function writeDouble (buf, value, offset, littleEndian, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    checkIEEE754(buf, value, offset, 8, 1.7976931348623157E+308, -1.7976931348623157E+308)
  }
  ieee754.write(buf, value, offset, littleEndian, 52, 8)
  return offset + 8
}

Buffer.prototype.writeDoubleLE = function writeDoubleLE (value, offset, noAssert) {
  return writeDouble(this, value, offset, true, noAssert)
}

Buffer.prototype.writeDoubleBE = function writeDoubleBE (value, offset, noAssert) {
  return writeDouble(this, value, offset, false, noAssert)
}

// copy(targetBuffer, targetStart=0, sourceStart=0, sourceEnd=buffer.length)
Buffer.prototype.copy = function copy (target, targetStart, start, end) {
  if (!Buffer.isBuffer(target)) throw new TypeError('argument should be a Buffer')
  if (!start) start = 0
  if (!end && end !== 0) end = this.length
  if (targetStart >= target.length) targetStart = target.length
  if (!targetStart) targetStart = 0
  if (end > 0 && end < start) end = start

  // Copy 0 bytes; we're done
  if (end === start) return 0
  if (target.length === 0 || this.length === 0) return 0

  // Fatal error conditions
  if (targetStart < 0) {
    throw new RangeError('targetStart out of bounds')
  }
  if (start < 0 || start >= this.length) throw new RangeError('Index out of range')
  if (end < 0) throw new RangeError('sourceEnd out of bounds')

  // Are we oob?
  if (end > this.length) end = this.length
  if (target.length - targetStart < end - start) {
    end = target.length - targetStart + start
  }

  var len = end - start

  if (this === target && typeof Uint8Array.prototype.copyWithin === 'function') {
    // Use built-in when available, missing from IE11
    this.copyWithin(targetStart, start, end)
  } else if (this === target && start < targetStart && targetStart < end) {
    // descending copy from end
    for (var i = len - 1; i >= 0; --i) {
      target[i + targetStart] = this[i + start]
    }
  } else {
    Uint8Array.prototype.set.call(
      target,
      this.subarray(start, end),
      targetStart
    )
  }

  return len
}

// Usage:
//    buffer.fill(number[, offset[, end]])
//    buffer.fill(buffer[, offset[, end]])
//    buffer.fill(string[, offset[, end]][, encoding])
Buffer.prototype.fill = function fill (val, start, end, encoding) {
  // Handle string cases:
  if (typeof val === 'string') {
    if (typeof start === 'string') {
      encoding = start
      start = 0
      end = this.length
    } else if (typeof end === 'string') {
      encoding = end
      end = this.length
    }
    if (encoding !== undefined && typeof encoding !== 'string') {
      throw new TypeError('encoding must be a string')
    }
    if (typeof encoding === 'string' && !Buffer.isEncoding(encoding)) {
      throw new TypeError('Unknown encoding: ' + encoding)
    }
    if (val.length === 1) {
      var code = val.charCodeAt(0)
      if ((encoding === 'utf8' && code < 128) ||
          encoding === 'latin1') {
        // Fast path: If `val` fits into a single byte, use that numeric value.
        val = code
      }
    }
  } else if (typeof val === 'number') {
    val = val & 255
  }

  // Invalid ranges are not set to a default, so can range check early.
  if (start < 0 || this.length < start || this.length < end) {
    throw new RangeError('Out of range index')
  }

  if (end <= start) {
    return this
  }

  start = start >>> 0
  end = end === undefined ? this.length : end >>> 0

  if (!val) val = 0

  var i
  if (typeof val === 'number') {
    for (i = start; i < end; ++i) {
      this[i] = val
    }
  } else {
    var bytes = Buffer.isBuffer(val)
      ? val
      : Buffer.from(val, encoding)
    var len = bytes.length
    if (len === 0) {
      throw new TypeError('The value "' + val +
        '" is invalid for argument "value"')
    }
    for (i = 0; i < end - start; ++i) {
      this[i + start] = bytes[i % len]
    }
  }

  return this
}

// HELPER FUNCTIONS
// ================

var INVALID_BASE64_RE = /[^+/0-9A-Za-z-_]/g

function base64clean (str) {
  // Node takes equal signs as end of the Base64 encoding
  str = str.split('=')[0]
  // Node strips out invalid characters like \n and \t from the string, base64-js does not
  str = str.trim().replace(INVALID_BASE64_RE, '')
  // Node converts strings with length < 2 to ''
  if (str.length < 2) return ''
  // Node allows for non-padded base64 strings (missing trailing ===), base64-js does not
  while (str.length % 4 !== 0) {
    str = str + '='
  }
  return str
}

function toHex (n) {
  if (n < 16) return '0' + n.toString(16)
  return n.toString(16)
}

function utf8ToBytes (string, units) {
  units = units || Infinity
  var codePoint
  var length = string.length
  var leadSurrogate = null
  var bytes = []

  for (var i = 0; i < length; ++i) {
    codePoint = string.charCodeAt(i)

    // is surrogate component
    if (codePoint > 0xD7FF && codePoint < 0xE000) {
      // last char was a lead
      if (!leadSurrogate) {
        // no lead yet
        if (codePoint > 0xDBFF) {
          // unexpected trail
          if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
          continue
        } else if (i + 1 === length) {
          // unpaired lead
          if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
          continue
        }

        // valid lead
        leadSurrogate = codePoint

        continue
      }

      // 2 leads in a row
      if (codePoint < 0xDC00) {
        if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
        leadSurrogate = codePoint
        continue
      }

      // valid surrogate pair
      codePoint = (leadSurrogate - 0xD800 << 10 | codePoint - 0xDC00) + 0x10000
    } else if (leadSurrogate) {
      // valid bmp char, but last char was a lead
      if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
    }

    leadSurrogate = null

    // encode utf8
    if (codePoint < 0x80) {
      if ((units -= 1) < 0) break
      bytes.push(codePoint)
    } else if (codePoint < 0x800) {
      if ((units -= 2) < 0) break
      bytes.push(
        codePoint >> 0x6 | 0xC0,
        codePoint & 0x3F | 0x80
      )
    } else if (codePoint < 0x10000) {
      if ((units -= 3) < 0) break
      bytes.push(
        codePoint >> 0xC | 0xE0,
        codePoint >> 0x6 & 0x3F | 0x80,
        codePoint & 0x3F | 0x80
      )
    } else if (codePoint < 0x110000) {
      if ((units -= 4) < 0) break
      bytes.push(
        codePoint >> 0x12 | 0xF0,
        codePoint >> 0xC & 0x3F | 0x80,
        codePoint >> 0x6 & 0x3F | 0x80,
        codePoint & 0x3F | 0x80
      )
    } else {
      throw new Error('Invalid code point')
    }
  }

  return bytes
}

function asciiToBytes (str) {
  var byteArray = []
  for (var i = 0; i < str.length; ++i) {
    // Node's code seems to be doing this and not & 0x7F..
    byteArray.push(str.charCodeAt(i) & 0xFF)
  }
  return byteArray
}

function utf16leToBytes (str, units) {
  var c, hi, lo
  var byteArray = []
  for (var i = 0; i < str.length; ++i) {
    if ((units -= 2) < 0) break

    c = str.charCodeAt(i)
    hi = c >> 8
    lo = c % 256
    byteArray.push(lo)
    byteArray.push(hi)
  }

  return byteArray
}

function base64ToBytes (str) {
  return base64.toByteArray(base64clean(str))
}

function blitBuffer (src, dst, offset, length) {
  for (var i = 0; i < length; ++i) {
    if ((i + offset >= dst.length) || (i >= src.length)) break
    dst[i + offset] = src[i]
  }
  return i
}

// ArrayBuffer or Uint8Array objects from other contexts (i.e. iframes) do not pass
// the `instanceof` check but they should be treated as of that type.
// See: https://github.com/feross/buffer/issues/166
function isInstance (obj, type) {
  return obj instanceof type ||
    (obj != null && obj.constructor != null && obj.constructor.name != null &&
      obj.constructor.name === type.name)
}
function numberIsNaN (obj) {
  // For IE11 support
  return obj !== obj // eslint-disable-line no-self-compare
}

},{"base64-js":20,"ieee754":30}],24:[function(require,module,exports){
module.exports = {
  "100": "Continue",
  "101": "Switching Protocols",
  "102": "Processing",
  "200": "OK",
  "201": "Created",
  "202": "Accepted",
  "203": "Non-Authoritative Information",
  "204": "No Content",
  "205": "Reset Content",
  "206": "Partial Content",
  "207": "Multi-Status",
  "208": "Already Reported",
  "226": "IM Used",
  "300": "Multiple Choices",
  "301": "Moved Permanently",
  "302": "Found",
  "303": "See Other",
  "304": "Not Modified",
  "305": "Use Proxy",
  "307": "Temporary Redirect",
  "308": "Permanent Redirect",
  "400": "Bad Request",
  "401": "Unauthorized",
  "402": "Payment Required",
  "403": "Forbidden",
  "404": "Not Found",
  "405": "Method Not Allowed",
  "406": "Not Acceptable",
  "407": "Proxy Authentication Required",
  "408": "Request Timeout",
  "409": "Conflict",
  "410": "Gone",
  "411": "Length Required",
  "412": "Precondition Failed",
  "413": "Payload Too Large",
  "414": "URI Too Long",
  "415": "Unsupported Media Type",
  "416": "Range Not Satisfiable",
  "417": "Expectation Failed",
  "418": "I'm a teapot",
  "421": "Misdirected Request",
  "422": "Unprocessable Entity",
  "423": "Locked",
  "424": "Failed Dependency",
  "425": "Unordered Collection",
  "426": "Upgrade Required",
  "428": "Precondition Required",
  "429": "Too Many Requests",
  "431": "Request Header Fields Too Large",
  "451": "Unavailable For Legal Reasons",
  "500": "Internal Server Error",
  "501": "Not Implemented",
  "502": "Bad Gateway",
  "503": "Service Unavailable",
  "504": "Gateway Timeout",
  "505": "HTTP Version Not Supported",
  "506": "Variant Also Negotiates",
  "507": "Insufficient Storage",
  "508": "Loop Detected",
  "509": "Bandwidth Limit Exceeded",
  "510": "Not Extended",
  "511": "Network Authentication Required"
}

},{}],25:[function(require,module,exports){
(function (process,global){
"use strict"

var next = (global.process && process.nextTick) || global.setImmediate || function (f) {
  setTimeout(f, 0)
}

module.exports = function maybe (cb, promise) {
  if (cb) {
    promise
      .then(function (result) {
        next(function () { cb(null, result) })
      }, function (err) {
        next(function () { cb(err) })
      })
    return undefined
  }
  else {
    return promise
  }
}

}).call(this,require('_process'),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{"_process":66}],26:[function(require,module,exports){
(function (Buffer){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// NOTE: These type checking functions intentionally don't use `instanceof`
// because it is fragile and can be easily faked with `Object.create()`.

function isArray(arg) {
  if (Array.isArray) {
    return Array.isArray(arg);
  }
  return objectToString(arg) === '[object Array]';
}
exports.isArray = isArray;

function isBoolean(arg) {
  return typeof arg === 'boolean';
}
exports.isBoolean = isBoolean;

function isNull(arg) {
  return arg === null;
}
exports.isNull = isNull;

function isNullOrUndefined(arg) {
  return arg == null;
}
exports.isNullOrUndefined = isNullOrUndefined;

function isNumber(arg) {
  return typeof arg === 'number';
}
exports.isNumber = isNumber;

function isString(arg) {
  return typeof arg === 'string';
}
exports.isString = isString;

function isSymbol(arg) {
  return typeof arg === 'symbol';
}
exports.isSymbol = isSymbol;

function isUndefined(arg) {
  return arg === void 0;
}
exports.isUndefined = isUndefined;

function isRegExp(re) {
  return objectToString(re) === '[object RegExp]';
}
exports.isRegExp = isRegExp;

function isObject(arg) {
  return typeof arg === 'object' && arg !== null;
}
exports.isObject = isObject;

function isDate(d) {
  return objectToString(d) === '[object Date]';
}
exports.isDate = isDate;

function isError(e) {
  return (objectToString(e) === '[object Error]' || e instanceof Error);
}
exports.isError = isError;

function isFunction(arg) {
  return typeof arg === 'function';
}
exports.isFunction = isFunction;

function isPrimitive(arg) {
  return arg === null ||
         typeof arg === 'boolean' ||
         typeof arg === 'number' ||
         typeof arg === 'string' ||
         typeof arg === 'symbol' ||  // ES6 symbol
         typeof arg === 'undefined';
}
exports.isPrimitive = isPrimitive;

exports.isBuffer = Buffer.isBuffer;

function objectToString(o) {
  return Object.prototype.toString.call(o);
}

}).call(this,{"isBuffer":require("../../is-buffer/index.js")})

},{"../../is-buffer/index.js":32}],27:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

var objectCreate = Object.create || objectCreatePolyfill
var objectKeys = Object.keys || objectKeysPolyfill
var bind = Function.prototype.bind || functionBindPolyfill

function EventEmitter() {
  if (!this._events || !Object.prototype.hasOwnProperty.call(this, '_events')) {
    this._events = objectCreate(null);
    this._eventsCount = 0;
  }

  this._maxListeners = this._maxListeners || undefined;
}
module.exports = EventEmitter;

// Backwards-compat with node 0.10.x
EventEmitter.EventEmitter = EventEmitter;

EventEmitter.prototype._events = undefined;
EventEmitter.prototype._maxListeners = undefined;

// By default EventEmitters will print a warning if more than 10 listeners are
// added to it. This is a useful default which helps finding memory leaks.
var defaultMaxListeners = 10;

var hasDefineProperty;
try {
  var o = {};
  if (Object.defineProperty) Object.defineProperty(o, 'x', { value: 0 });
  hasDefineProperty = o.x === 0;
} catch (err) { hasDefineProperty = false }
if (hasDefineProperty) {
  Object.defineProperty(EventEmitter, 'defaultMaxListeners', {
    enumerable: true,
    get: function() {
      return defaultMaxListeners;
    },
    set: function(arg) {
      // check whether the input is a positive number (whose value is zero or
      // greater and not a NaN).
      if (typeof arg !== 'number' || arg < 0 || arg !== arg)
        throw new TypeError('"defaultMaxListeners" must be a positive number');
      defaultMaxListeners = arg;
    }
  });
} else {
  EventEmitter.defaultMaxListeners = defaultMaxListeners;
}

// Obviously not all Emitters should be limited to 10. This function allows
// that to be increased. Set to zero for unlimited.
EventEmitter.prototype.setMaxListeners = function setMaxListeners(n) {
  if (typeof n !== 'number' || n < 0 || isNaN(n))
    throw new TypeError('"n" argument must be a positive number');
  this._maxListeners = n;
  return this;
};

function $getMaxListeners(that) {
  if (that._maxListeners === undefined)
    return EventEmitter.defaultMaxListeners;
  return that._maxListeners;
}

EventEmitter.prototype.getMaxListeners = function getMaxListeners() {
  return $getMaxListeners(this);
};

// These standalone emit* functions are used to optimize calling of event
// handlers for fast cases because emit() itself often has a variable number of
// arguments and can be deoptimized because of that. These functions always have
// the same number of arguments and thus do not get deoptimized, so the code
// inside them can execute faster.
function emitNone(handler, isFn, self) {
  if (isFn)
    handler.call(self);
  else {
    var len = handler.length;
    var listeners = arrayClone(handler, len);
    for (var i = 0; i < len; ++i)
      listeners[i].call(self);
  }
}
function emitOne(handler, isFn, self, arg1) {
  if (isFn)
    handler.call(self, arg1);
  else {
    var len = handler.length;
    var listeners = arrayClone(handler, len);
    for (var i = 0; i < len; ++i)
      listeners[i].call(self, arg1);
  }
}
function emitTwo(handler, isFn, self, arg1, arg2) {
  if (isFn)
    handler.call(self, arg1, arg2);
  else {
    var len = handler.length;
    var listeners = arrayClone(handler, len);
    for (var i = 0; i < len; ++i)
      listeners[i].call(self, arg1, arg2);
  }
}
function emitThree(handler, isFn, self, arg1, arg2, arg3) {
  if (isFn)
    handler.call(self, arg1, arg2, arg3);
  else {
    var len = handler.length;
    var listeners = arrayClone(handler, len);
    for (var i = 0; i < len; ++i)
      listeners[i].call(self, arg1, arg2, arg3);
  }
}

function emitMany(handler, isFn, self, args) {
  if (isFn)
    handler.apply(self, args);
  else {
    var len = handler.length;
    var listeners = arrayClone(handler, len);
    for (var i = 0; i < len; ++i)
      listeners[i].apply(self, args);
  }
}

EventEmitter.prototype.emit = function emit(type) {
  var er, handler, len, args, i, events;
  var doError = (type === 'error');

  events = this._events;
  if (events)
    doError = (doError && events.error == null);
  else if (!doError)
    return false;

  // If there is no 'error' event listener then throw.
  if (doError) {
    if (arguments.length > 1)
      er = arguments[1];
    if (er instanceof Error) {
      throw er; // Unhandled 'error' event
    } else {
      // At least give some kind of context to the user
      var err = new Error('Unhandled "error" event. (' + er + ')');
      err.context = er;
      throw err;
    }
    return false;
  }

  handler = events[type];

  if (!handler)
    return false;

  var isFn = typeof handler === 'function';
  len = arguments.length;
  switch (len) {
      // fast cases
    case 1:
      emitNone(handler, isFn, this);
      break;
    case 2:
      emitOne(handler, isFn, this, arguments[1]);
      break;
    case 3:
      emitTwo(handler, isFn, this, arguments[1], arguments[2]);
      break;
    case 4:
      emitThree(handler, isFn, this, arguments[1], arguments[2], arguments[3]);
      break;
      // slower
    default:
      args = new Array(len - 1);
      for (i = 1; i < len; i++)
        args[i - 1] = arguments[i];
      emitMany(handler, isFn, this, args);
  }

  return true;
};

function _addListener(target, type, listener, prepend) {
  var m;
  var events;
  var existing;

  if (typeof listener !== 'function')
    throw new TypeError('"listener" argument must be a function');

  events = target._events;
  if (!events) {
    events = target._events = objectCreate(null);
    target._eventsCount = 0;
  } else {
    // To avoid recursion in the case that type === "newListener"! Before
    // adding it to the listeners, first emit "newListener".
    if (events.newListener) {
      target.emit('newListener', type,
          listener.listener ? listener.listener : listener);

      // Re-assign `events` because a newListener handler could have caused the
      // this._events to be assigned to a new object
      events = target._events;
    }
    existing = events[type];
  }

  if (!existing) {
    // Optimize the case of one listener. Don't need the extra array object.
    existing = events[type] = listener;
    ++target._eventsCount;
  } else {
    if (typeof existing === 'function') {
      // Adding the second element, need to change to array.
      existing = events[type] =
          prepend ? [listener, existing] : [existing, listener];
    } else {
      // If we've already got an array, just append.
      if (prepend) {
        existing.unshift(listener);
      } else {
        existing.push(listener);
      }
    }

    // Check for listener leak
    if (!existing.warned) {
      m = $getMaxListeners(target);
      if (m && m > 0 && existing.length > m) {
        existing.warned = true;
        var w = new Error('Possible EventEmitter memory leak detected. ' +
            existing.length + ' "' + String(type) + '" listeners ' +
            'added. Use emitter.setMaxListeners() to ' +
            'increase limit.');
        w.name = 'MaxListenersExceededWarning';
        w.emitter = target;
        w.type = type;
        w.count = existing.length;
        if (typeof console === 'object' && console.warn) {
          console.warn('%s: %s', w.name, w.message);
        }
      }
    }
  }

  return target;
}

EventEmitter.prototype.addListener = function addListener(type, listener) {
  return _addListener(this, type, listener, false);
};

EventEmitter.prototype.on = EventEmitter.prototype.addListener;

EventEmitter.prototype.prependListener =
    function prependListener(type, listener) {
      return _addListener(this, type, listener, true);
    };

function onceWrapper() {
  if (!this.fired) {
    this.target.removeListener(this.type, this.wrapFn);
    this.fired = true;
    switch (arguments.length) {
      case 0:
        return this.listener.call(this.target);
      case 1:
        return this.listener.call(this.target, arguments[0]);
      case 2:
        return this.listener.call(this.target, arguments[0], arguments[1]);
      case 3:
        return this.listener.call(this.target, arguments[0], arguments[1],
            arguments[2]);
      default:
        var args = new Array(arguments.length);
        for (var i = 0; i < args.length; ++i)
          args[i] = arguments[i];
        this.listener.apply(this.target, args);
    }
  }
}

function _onceWrap(target, type, listener) {
  var state = { fired: false, wrapFn: undefined, target: target, type: type, listener: listener };
  var wrapped = bind.call(onceWrapper, state);
  wrapped.listener = listener;
  state.wrapFn = wrapped;
  return wrapped;
}

EventEmitter.prototype.once = function once(type, listener) {
  if (typeof listener !== 'function')
    throw new TypeError('"listener" argument must be a function');
  this.on(type, _onceWrap(this, type, listener));
  return this;
};

EventEmitter.prototype.prependOnceListener =
    function prependOnceListener(type, listener) {
      if (typeof listener !== 'function')
        throw new TypeError('"listener" argument must be a function');
      this.prependListener(type, _onceWrap(this, type, listener));
      return this;
    };

// Emits a 'removeListener' event if and only if the listener was removed.
EventEmitter.prototype.removeListener =
    function removeListener(type, listener) {
      var list, events, position, i, originalListener;

      if (typeof listener !== 'function')
        throw new TypeError('"listener" argument must be a function');

      events = this._events;
      if (!events)
        return this;

      list = events[type];
      if (!list)
        return this;

      if (list === listener || list.listener === listener) {
        if (--this._eventsCount === 0)
          this._events = objectCreate(null);
        else {
          delete events[type];
          if (events.removeListener)
            this.emit('removeListener', type, list.listener || listener);
        }
      } else if (typeof list !== 'function') {
        position = -1;

        for (i = list.length - 1; i >= 0; i--) {
          if (list[i] === listener || list[i].listener === listener) {
            originalListener = list[i].listener;
            position = i;
            break;
          }
        }

        if (position < 0)
          return this;

        if (position === 0)
          list.shift();
        else
          spliceOne(list, position);

        if (list.length === 1)
          events[type] = list[0];

        if (events.removeListener)
          this.emit('removeListener', type, originalListener || listener);
      }

      return this;
    };

EventEmitter.prototype.removeAllListeners =
    function removeAllListeners(type) {
      var listeners, events, i;

      events = this._events;
      if (!events)
        return this;

      // not listening for removeListener, no need to emit
      if (!events.removeListener) {
        if (arguments.length === 0) {
          this._events = objectCreate(null);
          this._eventsCount = 0;
        } else if (events[type]) {
          if (--this._eventsCount === 0)
            this._events = objectCreate(null);
          else
            delete events[type];
        }
        return this;
      }

      // emit removeListener for all listeners on all events
      if (arguments.length === 0) {
        var keys = objectKeys(events);
        var key;
        for (i = 0; i < keys.length; ++i) {
          key = keys[i];
          if (key === 'removeListener') continue;
          this.removeAllListeners(key);
        }
        this.removeAllListeners('removeListener');
        this._events = objectCreate(null);
        this._eventsCount = 0;
        return this;
      }

      listeners = events[type];

      if (typeof listeners === 'function') {
        this.removeListener(type, listeners);
      } else if (listeners) {
        // LIFO order
        for (i = listeners.length - 1; i >= 0; i--) {
          this.removeListener(type, listeners[i]);
        }
      }

      return this;
    };

function _listeners(target, type, unwrap) {
  var events = target._events;

  if (!events)
    return [];

  var evlistener = events[type];
  if (!evlistener)
    return [];

  if (typeof evlistener === 'function')
    return unwrap ? [evlistener.listener || evlistener] : [evlistener];

  return unwrap ? unwrapListeners(evlistener) : arrayClone(evlistener, evlistener.length);
}

EventEmitter.prototype.listeners = function listeners(type) {
  return _listeners(this, type, true);
};

EventEmitter.prototype.rawListeners = function rawListeners(type) {
  return _listeners(this, type, false);
};

EventEmitter.listenerCount = function(emitter, type) {
  if (typeof emitter.listenerCount === 'function') {
    return emitter.listenerCount(type);
  } else {
    return listenerCount.call(emitter, type);
  }
};

EventEmitter.prototype.listenerCount = listenerCount;
function listenerCount(type) {
  var events = this._events;

  if (events) {
    var evlistener = events[type];

    if (typeof evlistener === 'function') {
      return 1;
    } else if (evlistener) {
      return evlistener.length;
    }
  }

  return 0;
}

EventEmitter.prototype.eventNames = function eventNames() {
  return this._eventsCount > 0 ? Reflect.ownKeys(this._events) : [];
};

// About 1.5x faster than the two-arg version of Array#splice().
function spliceOne(list, index) {
  for (var i = index, k = i + 1, n = list.length; k < n; i += 1, k += 1)
    list[i] = list[k];
  list.pop();
}

function arrayClone(arr, n) {
  var copy = new Array(n);
  for (var i = 0; i < n; ++i)
    copy[i] = arr[i];
  return copy;
}

function unwrapListeners(arr) {
  var ret = new Array(arr.length);
  for (var i = 0; i < ret.length; ++i) {
    ret[i] = arr[i].listener || arr[i];
  }
  return ret;
}

function objectCreatePolyfill(proto) {
  var F = function() {};
  F.prototype = proto;
  return new F;
}
function objectKeysPolyfill(obj) {
  var keys = [];
  for (var k in obj) if (Object.prototype.hasOwnProperty.call(obj, k)) {
    keys.push(k);
  }
  return k;
}
function functionBindPolyfill(context) {
  var fn = this;
  return function () {
    return fn.apply(context, arguments);
  };
}

},{}],28:[function(require,module,exports){
function format(fmt) {
  var re = /(%?)(%([jds]))/g
    , args = Array.prototype.slice.call(arguments, 1);
  if(args.length) {
    fmt = fmt.replace(re, function(match, escaped, ptn, flag) {
      var arg = args.shift();
      switch(flag) {
        case 's':
          arg = '' + arg;
          break;
        case 'd':
          arg = Number(arg);
          break;
        case 'j':
          arg = JSON.stringify(arg);
          break;
      }
      if(!escaped) {
        return arg; 
      }
      args.unshift(arg);
      return match;
    })
  }

  // arguments remain after formatting
  if(args.length) {
    fmt += ' ' + args.join(' ');
  }

  // update escaped %% values
  fmt = fmt.replace(/%{2,2}/g, '%');

  return '' + fmt;
}

module.exports = format;

},{}],29:[function(require,module,exports){
var http = require('http')
var url = require('url')

var https = module.exports

for (var key in http) {
  if (http.hasOwnProperty(key)) https[key] = http[key]
}

https.request = function (params, cb) {
  params = validateParams(params)
  return http.request.call(this, params, cb)
}

https.get = function (params, cb) {
  params = validateParams(params)
  return http.get.call(this, params, cb)
}

function validateParams (params) {
  if (typeof params === 'string') {
    params = url.parse(params)
  }
  if (!params.protocol) {
    params.protocol = 'https:'
  }
  if (params.protocol !== 'https:') {
    throw new Error('Protocol "' + params.protocol + '" not supported. Expected "https:"')
  }
  return params
}

},{"http":80,"url":87}],30:[function(require,module,exports){
exports.read = function (buffer, offset, isLE, mLen, nBytes) {
  var e, m
  var eLen = (nBytes * 8) - mLen - 1
  var eMax = (1 << eLen) - 1
  var eBias = eMax >> 1
  var nBits = -7
  var i = isLE ? (nBytes - 1) : 0
  var d = isLE ? -1 : 1
  var s = buffer[offset + i]

  i += d

  e = s & ((1 << (-nBits)) - 1)
  s >>= (-nBits)
  nBits += eLen
  for (; nBits > 0; e = (e * 256) + buffer[offset + i], i += d, nBits -= 8) {}

  m = e & ((1 << (-nBits)) - 1)
  e >>= (-nBits)
  nBits += mLen
  for (; nBits > 0; m = (m * 256) + buffer[offset + i], i += d, nBits -= 8) {}

  if (e === 0) {
    e = 1 - eBias
  } else if (e === eMax) {
    return m ? NaN : ((s ? -1 : 1) * Infinity)
  } else {
    m = m + Math.pow(2, mLen)
    e = e - eBias
  }
  return (s ? -1 : 1) * m * Math.pow(2, e - mLen)
}

exports.write = function (buffer, value, offset, isLE, mLen, nBytes) {
  var e, m, c
  var eLen = (nBytes * 8) - mLen - 1
  var eMax = (1 << eLen) - 1
  var eBias = eMax >> 1
  var rt = (mLen === 23 ? Math.pow(2, -24) - Math.pow(2, -77) : 0)
  var i = isLE ? 0 : (nBytes - 1)
  var d = isLE ? 1 : -1
  var s = value < 0 || (value === 0 && 1 / value < 0) ? 1 : 0

  value = Math.abs(value)

  if (isNaN(value) || value === Infinity) {
    m = isNaN(value) ? 1 : 0
    e = eMax
  } else {
    e = Math.floor(Math.log(value) / Math.LN2)
    if (value * (c = Math.pow(2, -e)) < 1) {
      e--
      c *= 2
    }
    if (e + eBias >= 1) {
      value += rt / c
    } else {
      value += rt * Math.pow(2, 1 - eBias)
    }
    if (value * c >= 2) {
      e++
      c /= 2
    }

    if (e + eBias >= eMax) {
      m = 0
      e = eMax
    } else if (e + eBias >= 1) {
      m = ((value * c) - 1) * Math.pow(2, mLen)
      e = e + eBias
    } else {
      m = value * Math.pow(2, eBias - 1) * Math.pow(2, mLen)
      e = 0
    }
  }

  for (; mLen >= 8; buffer[offset + i] = m & 0xff, i += d, m /= 256, mLen -= 8) {}

  e = (e << mLen) | m
  eLen += mLen
  for (; eLen > 0; buffer[offset + i] = e & 0xff, i += d, e /= 256, eLen -= 8) {}

  buffer[offset + i - d] |= s * 128
}

},{}],31:[function(require,module,exports){
if (typeof Object.create === 'function') {
  // implementation from standard node.js 'util' module
  module.exports = function inherits(ctor, superCtor) {
    ctor.super_ = superCtor
    ctor.prototype = Object.create(superCtor.prototype, {
      constructor: {
        value: ctor,
        enumerable: false,
        writable: true,
        configurable: true
      }
    });
  };
} else {
  // old school shim for old browsers
  module.exports = function inherits(ctor, superCtor) {
    ctor.super_ = superCtor
    var TempCtor = function () {}
    TempCtor.prototype = superCtor.prototype
    ctor.prototype = new TempCtor()
    ctor.prototype.constructor = ctor
  }
}

},{}],32:[function(require,module,exports){
/*!
 * Determine if an object is a Buffer
 *
 * @author   Feross Aboukhadijeh <https://feross.org>
 * @license  MIT
 */

// The _isBuffer check is for Safari 5-7 support, because it's missing
// Object.prototype.constructor. Remove this eventually
module.exports = function (obj) {
  return obj != null && (isBuffer(obj) || isSlowBuffer(obj) || !!obj._isBuffer)
}

function isBuffer (obj) {
  return !!obj.constructor && typeof obj.constructor.isBuffer === 'function' && obj.constructor.isBuffer(obj)
}

// For Node v0.10 support. Remove this eventually.
function isSlowBuffer (obj) {
  return typeof obj.readFloatLE === 'function' && typeof obj.slice === 'function' && isBuffer(obj.slice(0, 0))
}

},{}],33:[function(require,module,exports){
var toString = {}.toString;

module.exports = Array.isArray || function (arr) {
  return toString.call(arr) == '[object Array]';
};

},{}],34:[function(require,module,exports){
'use strict';


var yaml = require('./lib/js-yaml.js');


module.exports = yaml;

},{"./lib/js-yaml.js":35}],35:[function(require,module,exports){
'use strict';


var loader = require('./js-yaml/loader');
var dumper = require('./js-yaml/dumper');


function deprecated(name) {
  return function () {
    throw new Error('Function ' + name + ' is deprecated and cannot be used.');
  };
}


module.exports.Type                = require('./js-yaml/type');
module.exports.Schema              = require('./js-yaml/schema');
module.exports.FAILSAFE_SCHEMA     = require('./js-yaml/schema/failsafe');
module.exports.JSON_SCHEMA         = require('./js-yaml/schema/json');
module.exports.CORE_SCHEMA         = require('./js-yaml/schema/core');
module.exports.DEFAULT_SAFE_SCHEMA = require('./js-yaml/schema/default_safe');
module.exports.DEFAULT_FULL_SCHEMA = require('./js-yaml/schema/default_full');
module.exports.load                = loader.load;
module.exports.loadAll             = loader.loadAll;
module.exports.safeLoad            = loader.safeLoad;
module.exports.safeLoadAll         = loader.safeLoadAll;
module.exports.dump                = dumper.dump;
module.exports.safeDump            = dumper.safeDump;
module.exports.YAMLException       = require('./js-yaml/exception');

// Deprecated schema names from JS-YAML 2.0.x
module.exports.MINIMAL_SCHEMA = require('./js-yaml/schema/failsafe');
module.exports.SAFE_SCHEMA    = require('./js-yaml/schema/default_safe');
module.exports.DEFAULT_SCHEMA = require('./js-yaml/schema/default_full');

// Deprecated functions from JS-YAML 1.x.x
module.exports.scan           = deprecated('scan');
module.exports.parse          = deprecated('parse');
module.exports.compose        = deprecated('compose');
module.exports.addConstructor = deprecated('addConstructor');

},{"./js-yaml/dumper":37,"./js-yaml/exception":38,"./js-yaml/loader":39,"./js-yaml/schema":41,"./js-yaml/schema/core":42,"./js-yaml/schema/default_full":43,"./js-yaml/schema/default_safe":44,"./js-yaml/schema/failsafe":45,"./js-yaml/schema/json":46,"./js-yaml/type":47}],36:[function(require,module,exports){
'use strict';


function isNothing(subject) {
  return (typeof subject === 'undefined') || (subject === null);
}


function isObject(subject) {
  return (typeof subject === 'object') && (subject !== null);
}


function toArray(sequence) {
  if (Array.isArray(sequence)) return sequence;
  else if (isNothing(sequence)) return [];

  return [ sequence ];
}


function extend(target, source) {
  var index, length, key, sourceKeys;

  if (source) {
    sourceKeys = Object.keys(source);

    for (index = 0, length = sourceKeys.length; index < length; index += 1) {
      key = sourceKeys[index];
      target[key] = source[key];
    }
  }

  return target;
}


function repeat(string, count) {
  var result = '', cycle;

  for (cycle = 0; cycle < count; cycle += 1) {
    result += string;
  }

  return result;
}


function isNegativeZero(number) {
  return (number === 0) && (Number.NEGATIVE_INFINITY === 1 / number);
}


module.exports.isNothing      = isNothing;
module.exports.isObject       = isObject;
module.exports.toArray        = toArray;
module.exports.repeat         = repeat;
module.exports.isNegativeZero = isNegativeZero;
module.exports.extend         = extend;

},{}],37:[function(require,module,exports){
'use strict';

/*eslint-disable no-use-before-define*/

var common              = require('./common');
var YAMLException       = require('./exception');
var DEFAULT_FULL_SCHEMA = require('./schema/default_full');
var DEFAULT_SAFE_SCHEMA = require('./schema/default_safe');

var _toString       = Object.prototype.toString;
var _hasOwnProperty = Object.prototype.hasOwnProperty;

var CHAR_TAB                  = 0x09; /* Tab */
var CHAR_LINE_FEED            = 0x0A; /* LF */
var CHAR_SPACE                = 0x20; /* Space */
var CHAR_EXCLAMATION          = 0x21; /* ! */
var CHAR_DOUBLE_QUOTE         = 0x22; /* " */
var CHAR_SHARP                = 0x23; /* # */
var CHAR_PERCENT              = 0x25; /* % */
var CHAR_AMPERSAND            = 0x26; /* & */
var CHAR_SINGLE_QUOTE         = 0x27; /* ' */
var CHAR_ASTERISK             = 0x2A; /* * */
var CHAR_COMMA                = 0x2C; /* , */
var CHAR_MINUS                = 0x2D; /* - */
var CHAR_COLON                = 0x3A; /* : */
var CHAR_GREATER_THAN         = 0x3E; /* > */
var CHAR_QUESTION             = 0x3F; /* ? */
var CHAR_COMMERCIAL_AT        = 0x40; /* @ */
var CHAR_LEFT_SQUARE_BRACKET  = 0x5B; /* [ */
var CHAR_RIGHT_SQUARE_BRACKET = 0x5D; /* ] */
var CHAR_GRAVE_ACCENT         = 0x60; /* ` */
var CHAR_LEFT_CURLY_BRACKET   = 0x7B; /* { */
var CHAR_VERTICAL_LINE        = 0x7C; /* | */
var CHAR_RIGHT_CURLY_BRACKET  = 0x7D; /* } */

var ESCAPE_SEQUENCES = {};

ESCAPE_SEQUENCES[0x00]   = '\\0';
ESCAPE_SEQUENCES[0x07]   = '\\a';
ESCAPE_SEQUENCES[0x08]   = '\\b';
ESCAPE_SEQUENCES[0x09]   = '\\t';
ESCAPE_SEQUENCES[0x0A]   = '\\n';
ESCAPE_SEQUENCES[0x0B]   = '\\v';
ESCAPE_SEQUENCES[0x0C]   = '\\f';
ESCAPE_SEQUENCES[0x0D]   = '\\r';
ESCAPE_SEQUENCES[0x1B]   = '\\e';
ESCAPE_SEQUENCES[0x22]   = '\\"';
ESCAPE_SEQUENCES[0x5C]   = '\\\\';
ESCAPE_SEQUENCES[0x85]   = '\\N';
ESCAPE_SEQUENCES[0xA0]   = '\\_';
ESCAPE_SEQUENCES[0x2028] = '\\L';
ESCAPE_SEQUENCES[0x2029] = '\\P';

var DEPRECATED_BOOLEANS_SYNTAX = [
  'y', 'Y', 'yes', 'Yes', 'YES', 'on', 'On', 'ON',
  'n', 'N', 'no', 'No', 'NO', 'off', 'Off', 'OFF'
];

function compileStyleMap(schema, map) {
  var result, keys, index, length, tag, style, type;

  if (map === null) return {};

  result = {};
  keys = Object.keys(map);

  for (index = 0, length = keys.length; index < length; index += 1) {
    tag = keys[index];
    style = String(map[tag]);

    if (tag.slice(0, 2) === '!!') {
      tag = 'tag:yaml.org,2002:' + tag.slice(2);
    }
    type = schema.compiledTypeMap['fallback'][tag];

    if (type && _hasOwnProperty.call(type.styleAliases, style)) {
      style = type.styleAliases[style];
    }

    result[tag] = style;
  }

  return result;
}

function encodeHex(character) {
  var string, handle, length;

  string = character.toString(16).toUpperCase();

  if (character <= 0xFF) {
    handle = 'x';
    length = 2;
  } else if (character <= 0xFFFF) {
    handle = 'u';
    length = 4;
  } else if (character <= 0xFFFFFFFF) {
    handle = 'U';
    length = 8;
  } else {
    throw new YAMLException('code point within a string may not be greater than 0xFFFFFFFF');
  }

  return '\\' + handle + common.repeat('0', length - string.length) + string;
}

function State(options) {
  this.schema        = options['schema'] || DEFAULT_FULL_SCHEMA;
  this.indent        = Math.max(1, (options['indent'] || 2));
  this.noArrayIndent = options['noArrayIndent'] || false;
  this.skipInvalid   = options['skipInvalid'] || false;
  this.flowLevel     = (common.isNothing(options['flowLevel']) ? -1 : options['flowLevel']);
  this.styleMap      = compileStyleMap(this.schema, options['styles'] || null);
  this.sortKeys      = options['sortKeys'] || false;
  this.lineWidth     = options['lineWidth'] || 80;
  this.noRefs        = options['noRefs'] || false;
  this.noCompatMode  = options['noCompatMode'] || false;
  this.condenseFlow  = options['condenseFlow'] || false;

  this.implicitTypes = this.schema.compiledImplicit;
  this.explicitTypes = this.schema.compiledExplicit;

  this.tag = null;
  this.result = '';

  this.duplicates = [];
  this.usedDuplicates = null;
}

// Indents every line in a string. Empty lines (\n only) are not indented.
function indentString(string, spaces) {
  var ind = common.repeat(' ', spaces),
      position = 0,
      next = -1,
      result = '',
      line,
      length = string.length;

  while (position < length) {
    next = string.indexOf('\n', position);
    if (next === -1) {
      line = string.slice(position);
      position = length;
    } else {
      line = string.slice(position, next + 1);
      position = next + 1;
    }

    if (line.length && line !== '\n') result += ind;

    result += line;
  }

  return result;
}

function generateNextLine(state, level) {
  return '\n' + common.repeat(' ', state.indent * level);
}

function testImplicitResolving(state, str) {
  var index, length, type;

  for (index = 0, length = state.implicitTypes.length; index < length; index += 1) {
    type = state.implicitTypes[index];

    if (type.resolve(str)) {
      return true;
    }
  }

  return false;
}

// [33] s-white ::= s-space | s-tab
function isWhitespace(c) {
  return c === CHAR_SPACE || c === CHAR_TAB;
}

// Returns true if the character can be printed without escaping.
// From YAML 1.2: "any allowed characters known to be non-printable
// should also be escaped. [However,] This isn’t mandatory"
// Derived from nb-char - \t - #x85 - #xA0 - #x2028 - #x2029.
function isPrintable(c) {
  return  (0x00020 <= c && c <= 0x00007E)
      || ((0x000A1 <= c && c <= 0x00D7FF) && c !== 0x2028 && c !== 0x2029)
      || ((0x0E000 <= c && c <= 0x00FFFD) && c !== 0xFEFF /* BOM */)
      ||  (0x10000 <= c && c <= 0x10FFFF);
}

// Simplified test for values allowed after the first character in plain style.
function isPlainSafe(c) {
  // Uses a subset of nb-char - c-flow-indicator - ":" - "#"
  // where nb-char ::= c-printable - b-char - c-byte-order-mark.
  return isPrintable(c) && c !== 0xFEFF
    // - c-flow-indicator
    && c !== CHAR_COMMA
    && c !== CHAR_LEFT_SQUARE_BRACKET
    && c !== CHAR_RIGHT_SQUARE_BRACKET
    && c !== CHAR_LEFT_CURLY_BRACKET
    && c !== CHAR_RIGHT_CURLY_BRACKET
    // - ":" - "#"
    && c !== CHAR_COLON
    && c !== CHAR_SHARP;
}

// Simplified test for values allowed as the first character in plain style.
function isPlainSafeFirst(c) {
  // Uses a subset of ns-char - c-indicator
  // where ns-char = nb-char - s-white.
  return isPrintable(c) && c !== 0xFEFF
    && !isWhitespace(c) // - s-white
    // - (c-indicator ::=
    // “-” | “?” | “:” | “,” | “[” | “]” | “{” | “}”
    && c !== CHAR_MINUS
    && c !== CHAR_QUESTION
    && c !== CHAR_COLON
    && c !== CHAR_COMMA
    && c !== CHAR_LEFT_SQUARE_BRACKET
    && c !== CHAR_RIGHT_SQUARE_BRACKET
    && c !== CHAR_LEFT_CURLY_BRACKET
    && c !== CHAR_RIGHT_CURLY_BRACKET
    // | “#” | “&” | “*” | “!” | “|” | “>” | “'” | “"”
    && c !== CHAR_SHARP
    && c !== CHAR_AMPERSAND
    && c !== CHAR_ASTERISK
    && c !== CHAR_EXCLAMATION
    && c !== CHAR_VERTICAL_LINE
    && c !== CHAR_GREATER_THAN
    && c !== CHAR_SINGLE_QUOTE
    && c !== CHAR_DOUBLE_QUOTE
    // | “%” | “@” | “`”)
    && c !== CHAR_PERCENT
    && c !== CHAR_COMMERCIAL_AT
    && c !== CHAR_GRAVE_ACCENT;
}

// Determines whether block indentation indicator is required.
function needIndentIndicator(string) {
  var leadingSpaceRe = /^\n* /;
  return leadingSpaceRe.test(string);
}

var STYLE_PLAIN   = 1,
    STYLE_SINGLE  = 2,
    STYLE_LITERAL = 3,
    STYLE_FOLDED  = 4,
    STYLE_DOUBLE  = 5;

// Determines which scalar styles are possible and returns the preferred style.
// lineWidth = -1 => no limit.
// Pre-conditions: str.length > 0.
// Post-conditions:
//    STYLE_PLAIN or STYLE_SINGLE => no \n are in the string.
//    STYLE_LITERAL => no lines are suitable for folding (or lineWidth is -1).
//    STYLE_FOLDED => a line > lineWidth and can be folded (and lineWidth != -1).
function chooseScalarStyle(string, singleLineOnly, indentPerLevel, lineWidth, testAmbiguousType) {
  var i;
  var char;
  var hasLineBreak = false;
  var hasFoldableLine = false; // only checked if shouldTrackWidth
  var shouldTrackWidth = lineWidth !== -1;
  var previousLineBreak = -1; // count the first line correctly
  var plain = isPlainSafeFirst(string.charCodeAt(0))
          && !isWhitespace(string.charCodeAt(string.length - 1));

  if (singleLineOnly) {
    // Case: no block styles.
    // Check for disallowed characters to rule out plain and single.
    for (i = 0; i < string.length; i++) {
      char = string.charCodeAt(i);
      if (!isPrintable(char)) {
        return STYLE_DOUBLE;
      }
      plain = plain && isPlainSafe(char);
    }
  } else {
    // Case: block styles permitted.
    for (i = 0; i < string.length; i++) {
      char = string.charCodeAt(i);
      if (char === CHAR_LINE_FEED) {
        hasLineBreak = true;
        // Check if any line can be folded.
        if (shouldTrackWidth) {
          hasFoldableLine = hasFoldableLine ||
            // Foldable line = too long, and not more-indented.
            (i - previousLineBreak - 1 > lineWidth &&
             string[previousLineBreak + 1] !== ' ');
          previousLineBreak = i;
        }
      } else if (!isPrintable(char)) {
        return STYLE_DOUBLE;
      }
      plain = plain && isPlainSafe(char);
    }
    // in case the end is missing a \n
    hasFoldableLine = hasFoldableLine || (shouldTrackWidth &&
      (i - previousLineBreak - 1 > lineWidth &&
       string[previousLineBreak + 1] !== ' '));
  }
  // Although every style can represent \n without escaping, prefer block styles
  // for multiline, since they're more readable and they don't add empty lines.
  // Also prefer folding a super-long line.
  if (!hasLineBreak && !hasFoldableLine) {
    // Strings interpretable as another type have to be quoted;
    // e.g. the string 'true' vs. the boolean true.
    return plain && !testAmbiguousType(string)
      ? STYLE_PLAIN : STYLE_SINGLE;
  }
  // Edge case: block indentation indicator can only have one digit.
  if (indentPerLevel > 9 && needIndentIndicator(string)) {
    return STYLE_DOUBLE;
  }
  // At this point we know block styles are valid.
  // Prefer literal style unless we want to fold.
  return hasFoldableLine ? STYLE_FOLDED : STYLE_LITERAL;
}

// Note: line breaking/folding is implemented for only the folded style.
// NB. We drop the last trailing newline (if any) of a returned block scalar
//  since the dumper adds its own newline. This always works:
//    • No ending newline => unaffected; already using strip "-" chomping.
//    • Ending newline    => removed then restored.
//  Importantly, this keeps the "+" chomp indicator from gaining an extra line.
function writeScalar(state, string, level, iskey) {
  state.dump = (function () {
    if (string.length === 0) {
      return "''";
    }
    if (!state.noCompatMode &&
        DEPRECATED_BOOLEANS_SYNTAX.indexOf(string) !== -1) {
      return "'" + string + "'";
    }

    var indent = state.indent * Math.max(1, level); // no 0-indent scalars
    // As indentation gets deeper, let the width decrease monotonically
    // to the lower bound min(state.lineWidth, 40).
    // Note that this implies
    //  state.lineWidth ≤ 40 + state.indent: width is fixed at the lower bound.
    //  state.lineWidth > 40 + state.indent: width decreases until the lower bound.
    // This behaves better than a constant minimum width which disallows narrower options,
    // or an indent threshold which causes the width to suddenly increase.
    var lineWidth = state.lineWidth === -1
      ? -1 : Math.max(Math.min(state.lineWidth, 40), state.lineWidth - indent);

    // Without knowing if keys are implicit/explicit, assume implicit for safety.
    var singleLineOnly = iskey
      // No block styles in flow mode.
      || (state.flowLevel > -1 && level >= state.flowLevel);
    function testAmbiguity(string) {
      return testImplicitResolving(state, string);
    }

    switch (chooseScalarStyle(string, singleLineOnly, state.indent, lineWidth, testAmbiguity)) {
      case STYLE_PLAIN:
        return string;
      case STYLE_SINGLE:
        return "'" + string.replace(/'/g, "''") + "'";
      case STYLE_LITERAL:
        return '|' + blockHeader(string, state.indent)
          + dropEndingNewline(indentString(string, indent));
      case STYLE_FOLDED:
        return '>' + blockHeader(string, state.indent)
          + dropEndingNewline(indentString(foldString(string, lineWidth), indent));
      case STYLE_DOUBLE:
        return '"' + escapeString(string, lineWidth) + '"';
      default:
        throw new YAMLException('impossible error: invalid scalar style');
    }
  }());
}

// Pre-conditions: string is valid for a block scalar, 1 <= indentPerLevel <= 9.
function blockHeader(string, indentPerLevel) {
  var indentIndicator = needIndentIndicator(string) ? String(indentPerLevel) : '';

  // note the special case: the string '\n' counts as a "trailing" empty line.
  var clip =          string[string.length - 1] === '\n';
  var keep = clip && (string[string.length - 2] === '\n' || string === '\n');
  var chomp = keep ? '+' : (clip ? '' : '-');

  return indentIndicator + chomp + '\n';
}

// (See the note for writeScalar.)
function dropEndingNewline(string) {
  return string[string.length - 1] === '\n' ? string.slice(0, -1) : string;
}

// Note: a long line without a suitable break point will exceed the width limit.
// Pre-conditions: every char in str isPrintable, str.length > 0, width > 0.
function foldString(string, width) {
  // In folded style, $k$ consecutive newlines output as $k+1$ newlines—
  // unless they're before or after a more-indented line, or at the very
  // beginning or end, in which case $k$ maps to $k$.
  // Therefore, parse each chunk as newline(s) followed by a content line.
  var lineRe = /(\n+)([^\n]*)/g;

  // first line (possibly an empty line)
  var result = (function () {
    var nextLF = string.indexOf('\n');
    nextLF = nextLF !== -1 ? nextLF : string.length;
    lineRe.lastIndex = nextLF;
    return foldLine(string.slice(0, nextLF), width);
  }());
  // If we haven't reached the first content line yet, don't add an extra \n.
  var prevMoreIndented = string[0] === '\n' || string[0] === ' ';
  var moreIndented;

  // rest of the lines
  var match;
  while ((match = lineRe.exec(string))) {
    var prefix = match[1], line = match[2];
    moreIndented = (line[0] === ' ');
    result += prefix
      + (!prevMoreIndented && !moreIndented && line !== ''
        ? '\n' : '')
      + foldLine(line, width);
    prevMoreIndented = moreIndented;
  }

  return result;
}

// Greedy line breaking.
// Picks the longest line under the limit each time,
// otherwise settles for the shortest line over the limit.
// NB. More-indented lines *cannot* be folded, as that would add an extra \n.
function foldLine(line, width) {
  if (line === '' || line[0] === ' ') return line;

  // Since a more-indented line adds a \n, breaks can't be followed by a space.
  var breakRe = / [^ ]/g; // note: the match index will always be <= length-2.
  var match;
  // start is an inclusive index. end, curr, and next are exclusive.
  var start = 0, end, curr = 0, next = 0;
  var result = '';

  // Invariants: 0 <= start <= length-1.
  //   0 <= curr <= next <= max(0, length-2). curr - start <= width.
  // Inside the loop:
  //   A match implies length >= 2, so curr and next are <= length-2.
  while ((match = breakRe.exec(line))) {
    next = match.index;
    // maintain invariant: curr - start <= width
    if (next - start > width) {
      end = (curr > start) ? curr : next; // derive end <= length-2
      result += '\n' + line.slice(start, end);
      // skip the space that was output as \n
      start = end + 1;                    // derive start <= length-1
    }
    curr = next;
  }

  // By the invariants, start <= length-1, so there is something left over.
  // It is either the whole string or a part starting from non-whitespace.
  result += '\n';
  // Insert a break if the remainder is too long and there is a break available.
  if (line.length - start > width && curr > start) {
    result += line.slice(start, curr) + '\n' + line.slice(curr + 1);
  } else {
    result += line.slice(start);
  }

  return result.slice(1); // drop extra \n joiner
}

// Escapes a double-quoted string.
function escapeString(string) {
  var result = '';
  var char, nextChar;
  var escapeSeq;

  for (var i = 0; i < string.length; i++) {
    char = string.charCodeAt(i);
    // Check for surrogate pairs (reference Unicode 3.0 section "3.7 Surrogates").
    if (char >= 0xD800 && char <= 0xDBFF/* high surrogate */) {
      nextChar = string.charCodeAt(i + 1);
      if (nextChar >= 0xDC00 && nextChar <= 0xDFFF/* low surrogate */) {
        // Combine the surrogate pair and store it escaped.
        result += encodeHex((char - 0xD800) * 0x400 + nextChar - 0xDC00 + 0x10000);
        // Advance index one extra since we already used that char here.
        i++; continue;
      }
    }
    escapeSeq = ESCAPE_SEQUENCES[char];
    result += !escapeSeq && isPrintable(char)
      ? string[i]
      : escapeSeq || encodeHex(char);
  }

  return result;
}

function writeFlowSequence(state, level, object) {
  var _result = '',
      _tag    = state.tag,
      index,
      length;

  for (index = 0, length = object.length; index < length; index += 1) {
    // Write only valid elements.
    if (writeNode(state, level, object[index], false, false)) {
      if (index !== 0) _result += ',' + (!state.condenseFlow ? ' ' : '');
      _result += state.dump;
    }
  }

  state.tag = _tag;
  state.dump = '[' + _result + ']';
}

function writeBlockSequence(state, level, object, compact) {
  var _result = '',
      _tag    = state.tag,
      index,
      length;

  for (index = 0, length = object.length; index < length; index += 1) {
    // Write only valid elements.
    if (writeNode(state, level + 1, object[index], true, true)) {
      if (!compact || index !== 0) {
        _result += generateNextLine(state, level);
      }

      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
        _result += '-';
      } else {
        _result += '- ';
      }

      _result += state.dump;
    }
  }

  state.tag = _tag;
  state.dump = _result || '[]'; // Empty sequence if no valid values.
}

function writeFlowMapping(state, level, object) {
  var _result       = '',
      _tag          = state.tag,
      objectKeyList = Object.keys(object),
      index,
      length,
      objectKey,
      objectValue,
      pairBuffer;

  for (index = 0, length = objectKeyList.length; index < length; index += 1) {
    pairBuffer = state.condenseFlow ? '"' : '';

    if (index !== 0) pairBuffer += ', ';

    objectKey = objectKeyList[index];
    objectValue = object[objectKey];

    if (!writeNode(state, level, objectKey, false, false)) {
      continue; // Skip this pair because of invalid key;
    }

    if (state.dump.length > 1024) pairBuffer += '? ';

    pairBuffer += state.dump + (state.condenseFlow ? '"' : '') + ':' + (state.condenseFlow ? '' : ' ');

    if (!writeNode(state, level, objectValue, false, false)) {
      continue; // Skip this pair because of invalid value.
    }

    pairBuffer += state.dump;

    // Both key and value are valid.
    _result += pairBuffer;
  }

  state.tag = _tag;
  state.dump = '{' + _result + '}';
}

function writeBlockMapping(state, level, object, compact) {
  var _result       = '',
      _tag          = state.tag,
      objectKeyList = Object.keys(object),
      index,
      length,
      objectKey,
      objectValue,
      explicitPair,
      pairBuffer;

  // Allow sorting keys so that the output file is deterministic
  if (state.sortKeys === true) {
    // Default sorting
    objectKeyList.sort();
  } else if (typeof state.sortKeys === 'function') {
    // Custom sort function
    objectKeyList.sort(state.sortKeys);
  } else if (state.sortKeys) {
    // Something is wrong
    throw new YAMLException('sortKeys must be a boolean or a function');
  }

  for (index = 0, length = objectKeyList.length; index < length; index += 1) {
    pairBuffer = '';

    if (!compact || index !== 0) {
      pairBuffer += generateNextLine(state, level);
    }

    objectKey = objectKeyList[index];
    objectValue = object[objectKey];

    if (!writeNode(state, level + 1, objectKey, true, true, true)) {
      continue; // Skip this pair because of invalid key.
    }

    explicitPair = (state.tag !== null && state.tag !== '?') ||
                   (state.dump && state.dump.length > 1024);

    if (explicitPair) {
      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
        pairBuffer += '?';
      } else {
        pairBuffer += '? ';
      }
    }

    pairBuffer += state.dump;

    if (explicitPair) {
      pairBuffer += generateNextLine(state, level);
    }

    if (!writeNode(state, level + 1, objectValue, true, explicitPair)) {
      continue; // Skip this pair because of invalid value.
    }

    if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
      pairBuffer += ':';
    } else {
      pairBuffer += ': ';
    }

    pairBuffer += state.dump;

    // Both key and value are valid.
    _result += pairBuffer;
  }

  state.tag = _tag;
  state.dump = _result || '{}'; // Empty mapping if no valid pairs.
}

function detectType(state, object, explicit) {
  var _result, typeList, index, length, type, style;

  typeList = explicit ? state.explicitTypes : state.implicitTypes;

  for (index = 0, length = typeList.length; index < length; index += 1) {
    type = typeList[index];

    if ((type.instanceOf  || type.predicate) &&
        (!type.instanceOf || ((typeof object === 'object') && (object instanceof type.instanceOf))) &&
        (!type.predicate  || type.predicate(object))) {

      state.tag = explicit ? type.tag : '?';

      if (type.represent) {
        style = state.styleMap[type.tag] || type.defaultStyle;

        if (_toString.call(type.represent) === '[object Function]') {
          _result = type.represent(object, style);
        } else if (_hasOwnProperty.call(type.represent, style)) {
          _result = type.represent[style](object, style);
        } else {
          throw new YAMLException('!<' + type.tag + '> tag resolver accepts not "' + style + '" style');
        }

        state.dump = _result;
      }

      return true;
    }
  }

  return false;
}

// Serializes `object` and writes it to global `result`.
// Returns true on success, or false on invalid object.
//
function writeNode(state, level, object, block, compact, iskey) {
  state.tag = null;
  state.dump = object;

  if (!detectType(state, object, false)) {
    detectType(state, object, true);
  }

  var type = _toString.call(state.dump);

  if (block) {
    block = (state.flowLevel < 0 || state.flowLevel > level);
  }

  var objectOrArray = type === '[object Object]' || type === '[object Array]',
      duplicateIndex,
      duplicate;

  if (objectOrArray) {
    duplicateIndex = state.duplicates.indexOf(object);
    duplicate = duplicateIndex !== -1;
  }

  if ((state.tag !== null && state.tag !== '?') || duplicate || (state.indent !== 2 && level > 0)) {
    compact = false;
  }

  if (duplicate && state.usedDuplicates[duplicateIndex]) {
    state.dump = '*ref_' + duplicateIndex;
  } else {
    if (objectOrArray && duplicate && !state.usedDuplicates[duplicateIndex]) {
      state.usedDuplicates[duplicateIndex] = true;
    }
    if (type === '[object Object]') {
      if (block && (Object.keys(state.dump).length !== 0)) {
        writeBlockMapping(state, level, state.dump, compact);
        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + state.dump;
        }
      } else {
        writeFlowMapping(state, level, state.dump);
        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
        }
      }
    } else if (type === '[object Array]') {
      var arrayLevel = (state.noArrayIndent) ? level - 1 : level;
      if (block && (state.dump.length !== 0)) {
        writeBlockSequence(state, arrayLevel, state.dump, compact);
        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + state.dump;
        }
      } else {
        writeFlowSequence(state, arrayLevel, state.dump);
        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
        }
      }
    } else if (type === '[object String]') {
      if (state.tag !== '?') {
        writeScalar(state, state.dump, level, iskey);
      }
    } else {
      if (state.skipInvalid) return false;
      throw new YAMLException('unacceptable kind of an object to dump ' + type);
    }

    if (state.tag !== null && state.tag !== '?') {
      state.dump = '!<' + state.tag + '> ' + state.dump;
    }
  }

  return true;
}

function getDuplicateReferences(object, state) {
  var objects = [],
      duplicatesIndexes = [],
      index,
      length;

  inspectNode(object, objects, duplicatesIndexes);

  for (index = 0, length = duplicatesIndexes.length; index < length; index += 1) {
    state.duplicates.push(objects[duplicatesIndexes[index]]);
  }
  state.usedDuplicates = new Array(length);
}

function inspectNode(object, objects, duplicatesIndexes) {
  var objectKeyList,
      index,
      length;

  if (object !== null && typeof object === 'object') {
    index = objects.indexOf(object);
    if (index !== -1) {
      if (duplicatesIndexes.indexOf(index) === -1) {
        duplicatesIndexes.push(index);
      }
    } else {
      objects.push(object);

      if (Array.isArray(object)) {
        for (index = 0, length = object.length; index < length; index += 1) {
          inspectNode(object[index], objects, duplicatesIndexes);
        }
      } else {
        objectKeyList = Object.keys(object);

        for (index = 0, length = objectKeyList.length; index < length; index += 1) {
          inspectNode(object[objectKeyList[index]], objects, duplicatesIndexes);
        }
      }
    }
  }
}

function dump(input, options) {
  options = options || {};

  var state = new State(options);

  if (!state.noRefs) getDuplicateReferences(input, state);

  if (writeNode(state, 0, input, true, true)) return state.dump + '\n';

  return '';
}

function safeDump(input, options) {
  return dump(input, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
}

module.exports.dump     = dump;
module.exports.safeDump = safeDump;

},{"./common":36,"./exception":38,"./schema/default_full":43,"./schema/default_safe":44}],38:[function(require,module,exports){
// YAML error class. http://stackoverflow.com/questions/8458984
//
'use strict';

function YAMLException(reason, mark) {
  // Super constructor
  Error.call(this);

  this.name = 'YAMLException';
  this.reason = reason;
  this.mark = mark;
  this.message = (this.reason || '(unknown reason)') + (this.mark ? ' ' + this.mark.toString() : '');

  // Include stack trace in error object
  if (Error.captureStackTrace) {
    // Chrome and NodeJS
    Error.captureStackTrace(this, this.constructor);
  } else {
    // FF, IE 10+ and Safari 6+. Fallback for others
    this.stack = (new Error()).stack || '';
  }
}


// Inherit from Error
YAMLException.prototype = Object.create(Error.prototype);
YAMLException.prototype.constructor = YAMLException;


YAMLException.prototype.toString = function toString(compact) {
  var result = this.name + ': ';

  result += this.reason || '(unknown reason)';

  if (!compact && this.mark) {
    result += ' ' + this.mark.toString();
  }

  return result;
};


module.exports = YAMLException;

},{}],39:[function(require,module,exports){
'use strict';

/*eslint-disable max-len,no-use-before-define*/

var common              = require('./common');
var YAMLException       = require('./exception');
var Mark                = require('./mark');
var DEFAULT_SAFE_SCHEMA = require('./schema/default_safe');
var DEFAULT_FULL_SCHEMA = require('./schema/default_full');


var _hasOwnProperty = Object.prototype.hasOwnProperty;


var CONTEXT_FLOW_IN   = 1;
var CONTEXT_FLOW_OUT  = 2;
var CONTEXT_BLOCK_IN  = 3;
var CONTEXT_BLOCK_OUT = 4;


var CHOMPING_CLIP  = 1;
var CHOMPING_STRIP = 2;
var CHOMPING_KEEP  = 3;


var PATTERN_NON_PRINTABLE         = /[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x84\x86-\x9F\uFFFE\uFFFF]|[\uD800-\uDBFF](?![\uDC00-\uDFFF])|(?:[^\uD800-\uDBFF]|^)[\uDC00-\uDFFF]/;
var PATTERN_NON_ASCII_LINE_BREAKS = /[\x85\u2028\u2029]/;
var PATTERN_FLOW_INDICATORS       = /[,\[\]\{\}]/;
var PATTERN_TAG_HANDLE            = /^(?:!|!!|![a-z\-]+!)$/i;
var PATTERN_TAG_URI               = /^(?:!|[^,\[\]\{\}])(?:%[0-9a-f]{2}|[0-9a-z\-#;\/\?:@&=\+\$,_\.!~\*'\(\)\[\]])*$/i;


function is_EOL(c) {
  return (c === 0x0A/* LF */) || (c === 0x0D/* CR */);
}

function is_WHITE_SPACE(c) {
  return (c === 0x09/* Tab */) || (c === 0x20/* Space */);
}

function is_WS_OR_EOL(c) {
  return (c === 0x09/* Tab */) ||
         (c === 0x20/* Space */) ||
         (c === 0x0A/* LF */) ||
         (c === 0x0D/* CR */);
}

function is_FLOW_INDICATOR(c) {
  return c === 0x2C/* , */ ||
         c === 0x5B/* [ */ ||
         c === 0x5D/* ] */ ||
         c === 0x7B/* { */ ||
         c === 0x7D/* } */;
}

function fromHexCode(c) {
  var lc;

  if ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) {
    return c - 0x30;
  }

  /*eslint-disable no-bitwise*/
  lc = c | 0x20;

  if ((0x61/* a */ <= lc) && (lc <= 0x66/* f */)) {
    return lc - 0x61 + 10;
  }

  return -1;
}

function escapedHexLen(c) {
  if (c === 0x78/* x */) { return 2; }
  if (c === 0x75/* u */) { return 4; }
  if (c === 0x55/* U */) { return 8; }
  return 0;
}

function fromDecimalCode(c) {
  if ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) {
    return c - 0x30;
  }

  return -1;
}

function simpleEscapeSequence(c) {
  /* eslint-disable indent */
  return (c === 0x30/* 0 */) ? '\x00' :
        (c === 0x61/* a */) ? '\x07' :
        (c === 0x62/* b */) ? '\x08' :
        (c === 0x74/* t */) ? '\x09' :
        (c === 0x09/* Tab */) ? '\x09' :
        (c === 0x6E/* n */) ? '\x0A' :
        (c === 0x76/* v */) ? '\x0B' :
        (c === 0x66/* f */) ? '\x0C' :
        (c === 0x72/* r */) ? '\x0D' :
        (c === 0x65/* e */) ? '\x1B' :
        (c === 0x20/* Space */) ? ' ' :
        (c === 0x22/* " */) ? '\x22' :
        (c === 0x2F/* / */) ? '/' :
        (c === 0x5C/* \ */) ? '\x5C' :
        (c === 0x4E/* N */) ? '\x85' :
        (c === 0x5F/* _ */) ? '\xA0' :
        (c === 0x4C/* L */) ? '\u2028' :
        (c === 0x50/* P */) ? '\u2029' : '';
}

function charFromCodepoint(c) {
  if (c <= 0xFFFF) {
    return String.fromCharCode(c);
  }
  // Encode UTF-16 surrogate pair
  // https://en.wikipedia.org/wiki/UTF-16#Code_points_U.2B010000_to_U.2B10FFFF
  return String.fromCharCode(
    ((c - 0x010000) >> 10) + 0xD800,
    ((c - 0x010000) & 0x03FF) + 0xDC00
  );
}

var simpleEscapeCheck = new Array(256); // integer, for fast access
var simpleEscapeMap = new Array(256);
for (var i = 0; i < 256; i++) {
  simpleEscapeCheck[i] = simpleEscapeSequence(i) ? 1 : 0;
  simpleEscapeMap[i] = simpleEscapeSequence(i);
}


function State(input, options) {
  this.input = input;

  this.filename  = options['filename']  || null;
  this.schema    = options['schema']    || DEFAULT_FULL_SCHEMA;
  this.onWarning = options['onWarning'] || null;
  this.legacy    = options['legacy']    || false;
  this.json      = options['json']      || false;
  this.listener  = options['listener']  || null;

  this.implicitTypes = this.schema.compiledImplicit;
  this.typeMap       = this.schema.compiledTypeMap;

  this.length     = input.length;
  this.position   = 0;
  this.line       = 0;
  this.lineStart  = 0;
  this.lineIndent = 0;

  this.documents = [];

  /*
  this.version;
  this.checkLineBreaks;
  this.tagMap;
  this.anchorMap;
  this.tag;
  this.anchor;
  this.kind;
  this.result;*/

}


function generateError(state, message) {
  return new YAMLException(
    message,
    new Mark(state.filename, state.input, state.position, state.line, (state.position - state.lineStart)));
}

function throwError(state, message) {
  throw generateError(state, message);
}

function throwWarning(state, message) {
  if (state.onWarning) {
    state.onWarning.call(null, generateError(state, message));
  }
}


var directiveHandlers = {

  YAML: function handleYamlDirective(state, name, args) {

    var match, major, minor;

    if (state.version !== null) {
      throwError(state, 'duplication of %YAML directive');
    }

    if (args.length !== 1) {
      throwError(state, 'YAML directive accepts exactly one argument');
    }

    match = /^([0-9]+)\.([0-9]+)$/.exec(args[0]);

    if (match === null) {
      throwError(state, 'ill-formed argument of the YAML directive');
    }

    major = parseInt(match[1], 10);
    minor = parseInt(match[2], 10);

    if (major !== 1) {
      throwError(state, 'unacceptable YAML version of the document');
    }

    state.version = args[0];
    state.checkLineBreaks = (minor < 2);

    if (minor !== 1 && minor !== 2) {
      throwWarning(state, 'unsupported YAML version of the document');
    }
  },

  TAG: function handleTagDirective(state, name, args) {

    var handle, prefix;

    if (args.length !== 2) {
      throwError(state, 'TAG directive accepts exactly two arguments');
    }

    handle = args[0];
    prefix = args[1];

    if (!PATTERN_TAG_HANDLE.test(handle)) {
      throwError(state, 'ill-formed tag handle (first argument) of the TAG directive');
    }

    if (_hasOwnProperty.call(state.tagMap, handle)) {
      throwError(state, 'there is a previously declared suffix for "' + handle + '" tag handle');
    }

    if (!PATTERN_TAG_URI.test(prefix)) {
      throwError(state, 'ill-formed tag prefix (second argument) of the TAG directive');
    }

    state.tagMap[handle] = prefix;
  }
};


function captureSegment(state, start, end, checkJson) {
  var _position, _length, _character, _result;

  if (start < end) {
    _result = state.input.slice(start, end);

    if (checkJson) {
      for (_position = 0, _length = _result.length; _position < _length; _position += 1) {
        _character = _result.charCodeAt(_position);
        if (!(_character === 0x09 ||
              (0x20 <= _character && _character <= 0x10FFFF))) {
          throwError(state, 'expected valid JSON character');
        }
      }
    } else if (PATTERN_NON_PRINTABLE.test(_result)) {
      throwError(state, 'the stream contains non-printable characters');
    }

    state.result += _result;
  }
}

function mergeMappings(state, destination, source, overridableKeys) {
  var sourceKeys, key, index, quantity;

  if (!common.isObject(source)) {
    throwError(state, 'cannot merge mappings; the provided source object is unacceptable');
  }

  sourceKeys = Object.keys(source);

  for (index = 0, quantity = sourceKeys.length; index < quantity; index += 1) {
    key = sourceKeys[index];

    if (!_hasOwnProperty.call(destination, key)) {
      destination[key] = source[key];
      overridableKeys[key] = true;
    }
  }
}

function storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode, startLine, startPos) {
  var index, quantity;

  keyNode = String(keyNode);

  if (_result === null) {
    _result = {};
  }

  if (keyTag === 'tag:yaml.org,2002:merge') {
    if (Array.isArray(valueNode)) {
      for (index = 0, quantity = valueNode.length; index < quantity; index += 1) {
        mergeMappings(state, _result, valueNode[index], overridableKeys);
      }
    } else {
      mergeMappings(state, _result, valueNode, overridableKeys);
    }
  } else {
    if (!state.json &&
        !_hasOwnProperty.call(overridableKeys, keyNode) &&
        _hasOwnProperty.call(_result, keyNode)) {
      state.line = startLine || state.line;
      state.position = startPos || state.position;
      throwError(state, 'duplicated mapping key');
    }
    _result[keyNode] = valueNode;
    delete overridableKeys[keyNode];
  }

  return _result;
}

function readLineBreak(state) {
  var ch;

  ch = state.input.charCodeAt(state.position);

  if (ch === 0x0A/* LF */) {
    state.position++;
  } else if (ch === 0x0D/* CR */) {
    state.position++;
    if (state.input.charCodeAt(state.position) === 0x0A/* LF */) {
      state.position++;
    }
  } else {
    throwError(state, 'a line break is expected');
  }

  state.line += 1;
  state.lineStart = state.position;
}

function skipSeparationSpace(state, allowComments, checkIndent) {
  var lineBreaks = 0,
      ch = state.input.charCodeAt(state.position);

  while (ch !== 0) {
    while (is_WHITE_SPACE(ch)) {
      ch = state.input.charCodeAt(++state.position);
    }

    if (allowComments && ch === 0x23/* # */) {
      do {
        ch = state.input.charCodeAt(++state.position);
      } while (ch !== 0x0A/* LF */ && ch !== 0x0D/* CR */ && ch !== 0);
    }

    if (is_EOL(ch)) {
      readLineBreak(state);

      ch = state.input.charCodeAt(state.position);
      lineBreaks++;
      state.lineIndent = 0;

      while (ch === 0x20/* Space */) {
        state.lineIndent++;
        ch = state.input.charCodeAt(++state.position);
      }
    } else {
      break;
    }
  }

  if (checkIndent !== -1 && lineBreaks !== 0 && state.lineIndent < checkIndent) {
    throwWarning(state, 'deficient indentation');
  }

  return lineBreaks;
}

function testDocumentSeparator(state) {
  var _position = state.position,
      ch;

  ch = state.input.charCodeAt(_position);

  // Condition state.position === state.lineStart is tested
  // in parent on each call, for efficiency. No needs to test here again.
  if ((ch === 0x2D/* - */ || ch === 0x2E/* . */) &&
      ch === state.input.charCodeAt(_position + 1) &&
      ch === state.input.charCodeAt(_position + 2)) {

    _position += 3;

    ch = state.input.charCodeAt(_position);

    if (ch === 0 || is_WS_OR_EOL(ch)) {
      return true;
    }
  }

  return false;
}

function writeFoldedLines(state, count) {
  if (count === 1) {
    state.result += ' ';
  } else if (count > 1) {
    state.result += common.repeat('\n', count - 1);
  }
}


function readPlainScalar(state, nodeIndent, withinFlowCollection) {
  var preceding,
      following,
      captureStart,
      captureEnd,
      hasPendingContent,
      _line,
      _lineStart,
      _lineIndent,
      _kind = state.kind,
      _result = state.result,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (is_WS_OR_EOL(ch)      ||
      is_FLOW_INDICATOR(ch) ||
      ch === 0x23/* # */    ||
      ch === 0x26/* & */    ||
      ch === 0x2A/* * */    ||
      ch === 0x21/* ! */    ||
      ch === 0x7C/* | */    ||
      ch === 0x3E/* > */    ||
      ch === 0x27/* ' */    ||
      ch === 0x22/* " */    ||
      ch === 0x25/* % */    ||
      ch === 0x40/* @ */    ||
      ch === 0x60/* ` */) {
    return false;
  }

  if (ch === 0x3F/* ? */ || ch === 0x2D/* - */) {
    following = state.input.charCodeAt(state.position + 1);

    if (is_WS_OR_EOL(following) ||
        withinFlowCollection && is_FLOW_INDICATOR(following)) {
      return false;
    }
  }

  state.kind = 'scalar';
  state.result = '';
  captureStart = captureEnd = state.position;
  hasPendingContent = false;

  while (ch !== 0) {
    if (ch === 0x3A/* : */) {
      following = state.input.charCodeAt(state.position + 1);

      if (is_WS_OR_EOL(following) ||
          withinFlowCollection && is_FLOW_INDICATOR(following)) {
        break;
      }

    } else if (ch === 0x23/* # */) {
      preceding = state.input.charCodeAt(state.position - 1);

      if (is_WS_OR_EOL(preceding)) {
        break;
      }

    } else if ((state.position === state.lineStart && testDocumentSeparator(state)) ||
               withinFlowCollection && is_FLOW_INDICATOR(ch)) {
      break;

    } else if (is_EOL(ch)) {
      _line = state.line;
      _lineStart = state.lineStart;
      _lineIndent = state.lineIndent;
      skipSeparationSpace(state, false, -1);

      if (state.lineIndent >= nodeIndent) {
        hasPendingContent = true;
        ch = state.input.charCodeAt(state.position);
        continue;
      } else {
        state.position = captureEnd;
        state.line = _line;
        state.lineStart = _lineStart;
        state.lineIndent = _lineIndent;
        break;
      }
    }

    if (hasPendingContent) {
      captureSegment(state, captureStart, captureEnd, false);
      writeFoldedLines(state, state.line - _line);
      captureStart = captureEnd = state.position;
      hasPendingContent = false;
    }

    if (!is_WHITE_SPACE(ch)) {
      captureEnd = state.position + 1;
    }

    ch = state.input.charCodeAt(++state.position);
  }

  captureSegment(state, captureStart, captureEnd, false);

  if (state.result) {
    return true;
  }

  state.kind = _kind;
  state.result = _result;
  return false;
}

function readSingleQuotedScalar(state, nodeIndent) {
  var ch,
      captureStart, captureEnd;

  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x27/* ' */) {
    return false;
  }

  state.kind = 'scalar';
  state.result = '';
  state.position++;
  captureStart = captureEnd = state.position;

  while ((ch = state.input.charCodeAt(state.position)) !== 0) {
    if (ch === 0x27/* ' */) {
      captureSegment(state, captureStart, state.position, true);
      ch = state.input.charCodeAt(++state.position);

      if (ch === 0x27/* ' */) {
        captureStart = state.position;
        state.position++;
        captureEnd = state.position;
      } else {
        return true;
      }

    } else if (is_EOL(ch)) {
      captureSegment(state, captureStart, captureEnd, true);
      writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
      captureStart = captureEnd = state.position;

    } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
      throwError(state, 'unexpected end of the document within a single quoted scalar');

    } else {
      state.position++;
      captureEnd = state.position;
    }
  }

  throwError(state, 'unexpected end of the stream within a single quoted scalar');
}

function readDoubleQuotedScalar(state, nodeIndent) {
  var captureStart,
      captureEnd,
      hexLength,
      hexResult,
      tmp,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x22/* " */) {
    return false;
  }

  state.kind = 'scalar';
  state.result = '';
  state.position++;
  captureStart = captureEnd = state.position;

  while ((ch = state.input.charCodeAt(state.position)) !== 0) {
    if (ch === 0x22/* " */) {
      captureSegment(state, captureStart, state.position, true);
      state.position++;
      return true;

    } else if (ch === 0x5C/* \ */) {
      captureSegment(state, captureStart, state.position, true);
      ch = state.input.charCodeAt(++state.position);

      if (is_EOL(ch)) {
        skipSeparationSpace(state, false, nodeIndent);

        // TODO: rework to inline fn with no type cast?
      } else if (ch < 256 && simpleEscapeCheck[ch]) {
        state.result += simpleEscapeMap[ch];
        state.position++;

      } else if ((tmp = escapedHexLen(ch)) > 0) {
        hexLength = tmp;
        hexResult = 0;

        for (; hexLength > 0; hexLength--) {
          ch = state.input.charCodeAt(++state.position);

          if ((tmp = fromHexCode(ch)) >= 0) {
            hexResult = (hexResult << 4) + tmp;

          } else {
            throwError(state, 'expected hexadecimal character');
          }
        }

        state.result += charFromCodepoint(hexResult);

        state.position++;

      } else {
        throwError(state, 'unknown escape sequence');
      }

      captureStart = captureEnd = state.position;

    } else if (is_EOL(ch)) {
      captureSegment(state, captureStart, captureEnd, true);
      writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
      captureStart = captureEnd = state.position;

    } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
      throwError(state, 'unexpected end of the document within a double quoted scalar');

    } else {
      state.position++;
      captureEnd = state.position;
    }
  }

  throwError(state, 'unexpected end of the stream within a double quoted scalar');
}

function readFlowCollection(state, nodeIndent) {
  var readNext = true,
      _line,
      _tag     = state.tag,
      _result,
      _anchor  = state.anchor,
      following,
      terminator,
      isPair,
      isExplicitPair,
      isMapping,
      overridableKeys = {},
      keyNode,
      keyTag,
      valueNode,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch === 0x5B/* [ */) {
    terminator = 0x5D;/* ] */
    isMapping = false;
    _result = [];
  } else if (ch === 0x7B/* { */) {
    terminator = 0x7D;/* } */
    isMapping = true;
    _result = {};
  } else {
    return false;
  }

  if (state.anchor !== null) {
    state.anchorMap[state.anchor] = _result;
  }

  ch = state.input.charCodeAt(++state.position);

  while (ch !== 0) {
    skipSeparationSpace(state, true, nodeIndent);

    ch = state.input.charCodeAt(state.position);

    if (ch === terminator) {
      state.position++;
      state.tag = _tag;
      state.anchor = _anchor;
      state.kind = isMapping ? 'mapping' : 'sequence';
      state.result = _result;
      return true;
    } else if (!readNext) {
      throwError(state, 'missed comma between flow collection entries');
    }

    keyTag = keyNode = valueNode = null;
    isPair = isExplicitPair = false;

    if (ch === 0x3F/* ? */) {
      following = state.input.charCodeAt(state.position + 1);

      if (is_WS_OR_EOL(following)) {
        isPair = isExplicitPair = true;
        state.position++;
        skipSeparationSpace(state, true, nodeIndent);
      }
    }

    _line = state.line;
    composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
    keyTag = state.tag;
    keyNode = state.result;
    skipSeparationSpace(state, true, nodeIndent);

    ch = state.input.charCodeAt(state.position);

    if ((isExplicitPair || state.line === _line) && ch === 0x3A/* : */) {
      isPair = true;
      ch = state.input.charCodeAt(++state.position);
      skipSeparationSpace(state, true, nodeIndent);
      composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
      valueNode = state.result;
    }

    if (isMapping) {
      storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode);
    } else if (isPair) {
      _result.push(storeMappingPair(state, null, overridableKeys, keyTag, keyNode, valueNode));
    } else {
      _result.push(keyNode);
    }

    skipSeparationSpace(state, true, nodeIndent);

    ch = state.input.charCodeAt(state.position);

    if (ch === 0x2C/* , */) {
      readNext = true;
      ch = state.input.charCodeAt(++state.position);
    } else {
      readNext = false;
    }
  }

  throwError(state, 'unexpected end of the stream within a flow collection');
}

function readBlockScalar(state, nodeIndent) {
  var captureStart,
      folding,
      chomping       = CHOMPING_CLIP,
      didReadContent = false,
      detectedIndent = false,
      textIndent     = nodeIndent,
      emptyLines     = 0,
      atMoreIndented = false,
      tmp,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch === 0x7C/* | */) {
    folding = false;
  } else if (ch === 0x3E/* > */) {
    folding = true;
  } else {
    return false;
  }

  state.kind = 'scalar';
  state.result = '';

  while (ch !== 0) {
    ch = state.input.charCodeAt(++state.position);

    if (ch === 0x2B/* + */ || ch === 0x2D/* - */) {
      if (CHOMPING_CLIP === chomping) {
        chomping = (ch === 0x2B/* + */) ? CHOMPING_KEEP : CHOMPING_STRIP;
      } else {
        throwError(state, 'repeat of a chomping mode identifier');
      }

    } else if ((tmp = fromDecimalCode(ch)) >= 0) {
      if (tmp === 0) {
        throwError(state, 'bad explicit indentation width of a block scalar; it cannot be less than one');
      } else if (!detectedIndent) {
        textIndent = nodeIndent + tmp - 1;
        detectedIndent = true;
      } else {
        throwError(state, 'repeat of an indentation width identifier');
      }

    } else {
      break;
    }
  }

  if (is_WHITE_SPACE(ch)) {
    do { ch = state.input.charCodeAt(++state.position); }
    while (is_WHITE_SPACE(ch));

    if (ch === 0x23/* # */) {
      do { ch = state.input.charCodeAt(++state.position); }
      while (!is_EOL(ch) && (ch !== 0));
    }
  }

  while (ch !== 0) {
    readLineBreak(state);
    state.lineIndent = 0;

    ch = state.input.charCodeAt(state.position);

    while ((!detectedIndent || state.lineIndent < textIndent) &&
           (ch === 0x20/* Space */)) {
      state.lineIndent++;
      ch = state.input.charCodeAt(++state.position);
    }

    if (!detectedIndent && state.lineIndent > textIndent) {
      textIndent = state.lineIndent;
    }

    if (is_EOL(ch)) {
      emptyLines++;
      continue;
    }

    // End of the scalar.
    if (state.lineIndent < textIndent) {

      // Perform the chomping.
      if (chomping === CHOMPING_KEEP) {
        state.result += common.repeat('\n', didReadContent ? 1 + emptyLines : emptyLines);
      } else if (chomping === CHOMPING_CLIP) {
        if (didReadContent) { // i.e. only if the scalar is not empty.
          state.result += '\n';
        }
      }

      // Break this `while` cycle and go to the funciton's epilogue.
      break;
    }

    // Folded style: use fancy rules to handle line breaks.
    if (folding) {

      // Lines starting with white space characters (more-indented lines) are not folded.
      if (is_WHITE_SPACE(ch)) {
        atMoreIndented = true;
        // except for the first content line (cf. Example 8.1)
        state.result += common.repeat('\n', didReadContent ? 1 + emptyLines : emptyLines);

      // End of more-indented block.
      } else if (atMoreIndented) {
        atMoreIndented = false;
        state.result += common.repeat('\n', emptyLines + 1);

      // Just one line break - perceive as the same line.
      } else if (emptyLines === 0) {
        if (didReadContent) { // i.e. only if we have already read some scalar content.
          state.result += ' ';
        }

      // Several line breaks - perceive as different lines.
      } else {
        state.result += common.repeat('\n', emptyLines);
      }

    // Literal style: just add exact number of line breaks between content lines.
    } else {
      // Keep all line breaks except the header line break.
      state.result += common.repeat('\n', didReadContent ? 1 + emptyLines : emptyLines);
    }

    didReadContent = true;
    detectedIndent = true;
    emptyLines = 0;
    captureStart = state.position;

    while (!is_EOL(ch) && (ch !== 0)) {
      ch = state.input.charCodeAt(++state.position);
    }

    captureSegment(state, captureStart, state.position, false);
  }

  return true;
}

function readBlockSequence(state, nodeIndent) {
  var _line,
      _tag      = state.tag,
      _anchor   = state.anchor,
      _result   = [],
      following,
      detected  = false,
      ch;

  if (state.anchor !== null) {
    state.anchorMap[state.anchor] = _result;
  }

  ch = state.input.charCodeAt(state.position);

  while (ch !== 0) {

    if (ch !== 0x2D/* - */) {
      break;
    }

    following = state.input.charCodeAt(state.position + 1);

    if (!is_WS_OR_EOL(following)) {
      break;
    }

    detected = true;
    state.position++;

    if (skipSeparationSpace(state, true, -1)) {
      if (state.lineIndent <= nodeIndent) {
        _result.push(null);
        ch = state.input.charCodeAt(state.position);
        continue;
      }
    }

    _line = state.line;
    composeNode(state, nodeIndent, CONTEXT_BLOCK_IN, false, true);
    _result.push(state.result);
    skipSeparationSpace(state, true, -1);

    ch = state.input.charCodeAt(state.position);

    if ((state.line === _line || state.lineIndent > nodeIndent) && (ch !== 0)) {
      throwError(state, 'bad indentation of a sequence entry');
    } else if (state.lineIndent < nodeIndent) {
      break;
    }
  }

  if (detected) {
    state.tag = _tag;
    state.anchor = _anchor;
    state.kind = 'sequence';
    state.result = _result;
    return true;
  }
  return false;
}

function readBlockMapping(state, nodeIndent, flowIndent) {
  var following,
      allowCompact,
      _line,
      _pos,
      _tag          = state.tag,
      _anchor       = state.anchor,
      _result       = {},
      overridableKeys = {},
      keyTag        = null,
      keyNode       = null,
      valueNode     = null,
      atExplicitKey = false,
      detected      = false,
      ch;

  if (state.anchor !== null) {
    state.anchorMap[state.anchor] = _result;
  }

  ch = state.input.charCodeAt(state.position);

  while (ch !== 0) {
    following = state.input.charCodeAt(state.position + 1);
    _line = state.line; // Save the current line.
    _pos = state.position;

    //
    // Explicit notation case. There are two separate blocks:
    // first for the key (denoted by "?") and second for the value (denoted by ":")
    //
    if ((ch === 0x3F/* ? */ || ch === 0x3A/* : */) && is_WS_OR_EOL(following)) {

      if (ch === 0x3F/* ? */) {
        if (atExplicitKey) {
          storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, null);
          keyTag = keyNode = valueNode = null;
        }

        detected = true;
        atExplicitKey = true;
        allowCompact = true;

      } else if (atExplicitKey) {
        // i.e. 0x3A/* : */ === character after the explicit key.
        atExplicitKey = false;
        allowCompact = true;

      } else {
        throwError(state, 'incomplete explicit mapping pair; a key node is missed; or followed by a non-tabulated empty line');
      }

      state.position += 1;
      ch = following;

    //
    // Implicit notation case. Flow-style node as the key first, then ":", and the value.
    //
    } else if (composeNode(state, flowIndent, CONTEXT_FLOW_OUT, false, true)) {

      if (state.line === _line) {
        ch = state.input.charCodeAt(state.position);

        while (is_WHITE_SPACE(ch)) {
          ch = state.input.charCodeAt(++state.position);
        }

        if (ch === 0x3A/* : */) {
          ch = state.input.charCodeAt(++state.position);

          if (!is_WS_OR_EOL(ch)) {
            throwError(state, 'a whitespace character is expected after the key-value separator within a block mapping');
          }

          if (atExplicitKey) {
            storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, null);
            keyTag = keyNode = valueNode = null;
          }

          detected = true;
          atExplicitKey = false;
          allowCompact = false;
          keyTag = state.tag;
          keyNode = state.result;

        } else if (detected) {
          throwError(state, 'can not read an implicit mapping pair; a colon is missed');

        } else {
          state.tag = _tag;
          state.anchor = _anchor;
          return true; // Keep the result of `composeNode`.
        }

      } else if (detected) {
        throwError(state, 'can not read a block mapping entry; a multiline key may not be an implicit key');

      } else {
        state.tag = _tag;
        state.anchor = _anchor;
        return true; // Keep the result of `composeNode`.
      }

    } else {
      break; // Reading is done. Go to the epilogue.
    }

    //
    // Common reading code for both explicit and implicit notations.
    //
    if (state.line === _line || state.lineIndent > nodeIndent) {
      if (composeNode(state, nodeIndent, CONTEXT_BLOCK_OUT, true, allowCompact)) {
        if (atExplicitKey) {
          keyNode = state.result;
        } else {
          valueNode = state.result;
        }
      }

      if (!atExplicitKey) {
        storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode, _line, _pos);
        keyTag = keyNode = valueNode = null;
      }

      skipSeparationSpace(state, true, -1);
      ch = state.input.charCodeAt(state.position);
    }

    if (state.lineIndent > nodeIndent && (ch !== 0)) {
      throwError(state, 'bad indentation of a mapping entry');
    } else if (state.lineIndent < nodeIndent) {
      break;
    }
  }

  //
  // Epilogue.
  //

  // Special case: last mapping's node contains only the key in explicit notation.
  if (atExplicitKey) {
    storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, null);
  }

  // Expose the resulting mapping.
  if (detected) {
    state.tag = _tag;
    state.anchor = _anchor;
    state.kind = 'mapping';
    state.result = _result;
  }

  return detected;
}

function readTagProperty(state) {
  var _position,
      isVerbatim = false,
      isNamed    = false,
      tagHandle,
      tagName,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x21/* ! */) return false;

  if (state.tag !== null) {
    throwError(state, 'duplication of a tag property');
  }

  ch = state.input.charCodeAt(++state.position);

  if (ch === 0x3C/* < */) {
    isVerbatim = true;
    ch = state.input.charCodeAt(++state.position);

  } else if (ch === 0x21/* ! */) {
    isNamed = true;
    tagHandle = '!!';
    ch = state.input.charCodeAt(++state.position);

  } else {
    tagHandle = '!';
  }

  _position = state.position;

  if (isVerbatim) {
    do { ch = state.input.charCodeAt(++state.position); }
    while (ch !== 0 && ch !== 0x3E/* > */);

    if (state.position < state.length) {
      tagName = state.input.slice(_position, state.position);
      ch = state.input.charCodeAt(++state.position);
    } else {
      throwError(state, 'unexpected end of the stream within a verbatim tag');
    }
  } else {
    while (ch !== 0 && !is_WS_OR_EOL(ch)) {

      if (ch === 0x21/* ! */) {
        if (!isNamed) {
          tagHandle = state.input.slice(_position - 1, state.position + 1);

          if (!PATTERN_TAG_HANDLE.test(tagHandle)) {
            throwError(state, 'named tag handle cannot contain such characters');
          }

          isNamed = true;
          _position = state.position + 1;
        } else {
          throwError(state, 'tag suffix cannot contain exclamation marks');
        }
      }

      ch = state.input.charCodeAt(++state.position);
    }

    tagName = state.input.slice(_position, state.position);

    if (PATTERN_FLOW_INDICATORS.test(tagName)) {
      throwError(state, 'tag suffix cannot contain flow indicator characters');
    }
  }

  if (tagName && !PATTERN_TAG_URI.test(tagName)) {
    throwError(state, 'tag name cannot contain such characters: ' + tagName);
  }

  if (isVerbatim) {
    state.tag = tagName;

  } else if (_hasOwnProperty.call(state.tagMap, tagHandle)) {
    state.tag = state.tagMap[tagHandle] + tagName;

  } else if (tagHandle === '!') {
    state.tag = '!' + tagName;

  } else if (tagHandle === '!!') {
    state.tag = 'tag:yaml.org,2002:' + tagName;

  } else {
    throwError(state, 'undeclared tag handle "' + tagHandle + '"');
  }

  return true;
}

function readAnchorProperty(state) {
  var _position,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x26/* & */) return false;

  if (state.anchor !== null) {
    throwError(state, 'duplication of an anchor property');
  }

  ch = state.input.charCodeAt(++state.position);
  _position = state.position;

  while (ch !== 0 && !is_WS_OR_EOL(ch) && !is_FLOW_INDICATOR(ch)) {
    ch = state.input.charCodeAt(++state.position);
  }

  if (state.position === _position) {
    throwError(state, 'name of an anchor node must contain at least one character');
  }

  state.anchor = state.input.slice(_position, state.position);
  return true;
}

function readAlias(state) {
  var _position, alias,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x2A/* * */) return false;

  ch = state.input.charCodeAt(++state.position);
  _position = state.position;

  while (ch !== 0 && !is_WS_OR_EOL(ch) && !is_FLOW_INDICATOR(ch)) {
    ch = state.input.charCodeAt(++state.position);
  }

  if (state.position === _position) {
    throwError(state, 'name of an alias node must contain at least one character');
  }

  alias = state.input.slice(_position, state.position);

  if (!state.anchorMap.hasOwnProperty(alias)) {
    throwError(state, 'unidentified alias "' + alias + '"');
  }

  state.result = state.anchorMap[alias];
  skipSeparationSpace(state, true, -1);
  return true;
}

function composeNode(state, parentIndent, nodeContext, allowToSeek, allowCompact) {
  var allowBlockStyles,
      allowBlockScalars,
      allowBlockCollections,
      indentStatus = 1, // 1: this>parent, 0: this=parent, -1: this<parent
      atNewLine  = false,
      hasContent = false,
      typeIndex,
      typeQuantity,
      type,
      flowIndent,
      blockIndent;

  if (state.listener !== null) {
    state.listener('open', state);
  }

  state.tag    = null;
  state.anchor = null;
  state.kind   = null;
  state.result = null;

  allowBlockStyles = allowBlockScalars = allowBlockCollections =
    CONTEXT_BLOCK_OUT === nodeContext ||
    CONTEXT_BLOCK_IN  === nodeContext;

  if (allowToSeek) {
    if (skipSeparationSpace(state, true, -1)) {
      atNewLine = true;

      if (state.lineIndent > parentIndent) {
        indentStatus = 1;
      } else if (state.lineIndent === parentIndent) {
        indentStatus = 0;
      } else if (state.lineIndent < parentIndent) {
        indentStatus = -1;
      }
    }
  }

  if (indentStatus === 1) {
    while (readTagProperty(state) || readAnchorProperty(state)) {
      if (skipSeparationSpace(state, true, -1)) {
        atNewLine = true;
        allowBlockCollections = allowBlockStyles;

        if (state.lineIndent > parentIndent) {
          indentStatus = 1;
        } else if (state.lineIndent === parentIndent) {
          indentStatus = 0;
        } else if (state.lineIndent < parentIndent) {
          indentStatus = -1;
        }
      } else {
        allowBlockCollections = false;
      }
    }
  }

  if (allowBlockCollections) {
    allowBlockCollections = atNewLine || allowCompact;
  }

  if (indentStatus === 1 || CONTEXT_BLOCK_OUT === nodeContext) {
    if (CONTEXT_FLOW_IN === nodeContext || CONTEXT_FLOW_OUT === nodeContext) {
      flowIndent = parentIndent;
    } else {
      flowIndent = parentIndent + 1;
    }

    blockIndent = state.position - state.lineStart;

    if (indentStatus === 1) {
      if (allowBlockCollections &&
          (readBlockSequence(state, blockIndent) ||
           readBlockMapping(state, blockIndent, flowIndent)) ||
          readFlowCollection(state, flowIndent)) {
        hasContent = true;
      } else {
        if ((allowBlockScalars && readBlockScalar(state, flowIndent)) ||
            readSingleQuotedScalar(state, flowIndent) ||
            readDoubleQuotedScalar(state, flowIndent)) {
          hasContent = true;

        } else if (readAlias(state)) {
          hasContent = true;

          if (state.tag !== null || state.anchor !== null) {
            throwError(state, 'alias node should not have any properties');
          }

        } else if (readPlainScalar(state, flowIndent, CONTEXT_FLOW_IN === nodeContext)) {
          hasContent = true;

          if (state.tag === null) {
            state.tag = '?';
          }
        }

        if (state.anchor !== null) {
          state.anchorMap[state.anchor] = state.result;
        }
      }
    } else if (indentStatus === 0) {
      // Special case: block sequences are allowed to have same indentation level as the parent.
      // http://www.yaml.org/spec/1.2/spec.html#id2799784
      hasContent = allowBlockCollections && readBlockSequence(state, blockIndent);
    }
  }

  if (state.tag !== null && state.tag !== '!') {
    if (state.tag === '?') {
      for (typeIndex = 0, typeQuantity = state.implicitTypes.length; typeIndex < typeQuantity; typeIndex += 1) {
        type = state.implicitTypes[typeIndex];

        // Implicit resolving is not allowed for non-scalar types, and '?'
        // non-specific tag is only assigned to plain scalars. So, it isn't
        // needed to check for 'kind' conformity.

        if (type.resolve(state.result)) { // `state.result` updated in resolver if matched
          state.result = type.construct(state.result);
          state.tag = type.tag;
          if (state.anchor !== null) {
            state.anchorMap[state.anchor] = state.result;
          }
          break;
        }
      }
    } else if (_hasOwnProperty.call(state.typeMap[state.kind || 'fallback'], state.tag)) {
      type = state.typeMap[state.kind || 'fallback'][state.tag];

      if (state.result !== null && type.kind !== state.kind) {
        throwError(state, 'unacceptable node kind for !<' + state.tag + '> tag; it should be "' + type.kind + '", not "' + state.kind + '"');
      }

      if (!type.resolve(state.result)) { // `state.result` updated in resolver if matched
        throwError(state, 'cannot resolve a node with !<' + state.tag + '> explicit tag');
      } else {
        state.result = type.construct(state.result);
        if (state.anchor !== null) {
          state.anchorMap[state.anchor] = state.result;
        }
      }
    } else {
      throwError(state, 'unknown tag !<' + state.tag + '>');
    }
  }

  if (state.listener !== null) {
    state.listener('close', state);
  }
  return state.tag !== null ||  state.anchor !== null || hasContent;
}

function readDocument(state) {
  var documentStart = state.position,
      _position,
      directiveName,
      directiveArgs,
      hasDirectives = false,
      ch;

  state.version = null;
  state.checkLineBreaks = state.legacy;
  state.tagMap = {};
  state.anchorMap = {};

  while ((ch = state.input.charCodeAt(state.position)) !== 0) {
    skipSeparationSpace(state, true, -1);

    ch = state.input.charCodeAt(state.position);

    if (state.lineIndent > 0 || ch !== 0x25/* % */) {
      break;
    }

    hasDirectives = true;
    ch = state.input.charCodeAt(++state.position);
    _position = state.position;

    while (ch !== 0 && !is_WS_OR_EOL(ch)) {
      ch = state.input.charCodeAt(++state.position);
    }

    directiveName = state.input.slice(_position, state.position);
    directiveArgs = [];

    if (directiveName.length < 1) {
      throwError(state, 'directive name must not be less than one character in length');
    }

    while (ch !== 0) {
      while (is_WHITE_SPACE(ch)) {
        ch = state.input.charCodeAt(++state.position);
      }

      if (ch === 0x23/* # */) {
        do { ch = state.input.charCodeAt(++state.position); }
        while (ch !== 0 && !is_EOL(ch));
        break;
      }

      if (is_EOL(ch)) break;

      _position = state.position;

      while (ch !== 0 && !is_WS_OR_EOL(ch)) {
        ch = state.input.charCodeAt(++state.position);
      }

      directiveArgs.push(state.input.slice(_position, state.position));
    }

    if (ch !== 0) readLineBreak(state);

    if (_hasOwnProperty.call(directiveHandlers, directiveName)) {
      directiveHandlers[directiveName](state, directiveName, directiveArgs);
    } else {
      throwWarning(state, 'unknown document directive "' + directiveName + '"');
    }
  }

  skipSeparationSpace(state, true, -1);

  if (state.lineIndent === 0 &&
      state.input.charCodeAt(state.position)     === 0x2D/* - */ &&
      state.input.charCodeAt(state.position + 1) === 0x2D/* - */ &&
      state.input.charCodeAt(state.position + 2) === 0x2D/* - */) {
    state.position += 3;
    skipSeparationSpace(state, true, -1);

  } else if (hasDirectives) {
    throwError(state, 'directives end mark is expected');
  }

  composeNode(state, state.lineIndent - 1, CONTEXT_BLOCK_OUT, false, true);
  skipSeparationSpace(state, true, -1);

  if (state.checkLineBreaks &&
      PATTERN_NON_ASCII_LINE_BREAKS.test(state.input.slice(documentStart, state.position))) {
    throwWarning(state, 'non-ASCII line breaks are interpreted as content');
  }

  state.documents.push(state.result);

  if (state.position === state.lineStart && testDocumentSeparator(state)) {

    if (state.input.charCodeAt(state.position) === 0x2E/* . */) {
      state.position += 3;
      skipSeparationSpace(state, true, -1);
    }
    return;
  }

  if (state.position < (state.length - 1)) {
    throwError(state, 'end of the stream or a document separator is expected');
  } else {
    return;
  }
}


function loadDocuments(input, options) {
  input = String(input);
  options = options || {};

  if (input.length !== 0) {

    // Add tailing `\n` if not exists
    if (input.charCodeAt(input.length - 1) !== 0x0A/* LF */ &&
        input.charCodeAt(input.length - 1) !== 0x0D/* CR */) {
      input += '\n';
    }

    // Strip BOM
    if (input.charCodeAt(0) === 0xFEFF) {
      input = input.slice(1);
    }
  }

  var state = new State(input, options);

  // Use 0 as string terminator. That significantly simplifies bounds check.
  state.input += '\0';

  while (state.input.charCodeAt(state.position) === 0x20/* Space */) {
    state.lineIndent += 1;
    state.position += 1;
  }

  while (state.position < (state.length - 1)) {
    readDocument(state);
  }

  return state.documents;
}


function loadAll(input, iterator, options) {
  var documents = loadDocuments(input, options), index, length;

  if (typeof iterator !== 'function') {
    return documents;
  }

  for (index = 0, length = documents.length; index < length; index += 1) {
    iterator(documents[index]);
  }
}


function load(input, options) {
  var documents = loadDocuments(input, options);

  if (documents.length === 0) {
    /*eslint-disable no-undefined*/
    return undefined;
  } else if (documents.length === 1) {
    return documents[0];
  }
  throw new YAMLException('expected a single document in the stream, but found more');
}


function safeLoadAll(input, output, options) {
  if (typeof output === 'function') {
    loadAll(input, output, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
  } else {
    return loadAll(input, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
  }
}


function safeLoad(input, options) {
  return load(input, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
}


module.exports.loadAll     = loadAll;
module.exports.load        = load;
module.exports.safeLoadAll = safeLoadAll;
module.exports.safeLoad    = safeLoad;

},{"./common":36,"./exception":38,"./mark":40,"./schema/default_full":43,"./schema/default_safe":44}],40:[function(require,module,exports){
'use strict';


var common = require('./common');


function Mark(name, buffer, position, line, column) {
  this.name     = name;
  this.buffer   = buffer;
  this.position = position;
  this.line     = line;
  this.column   = column;
}


Mark.prototype.getSnippet = function getSnippet(indent, maxLength) {
  var head, start, tail, end, snippet;

  if (!this.buffer) return null;

  indent = indent || 4;
  maxLength = maxLength || 75;

  head = '';
  start = this.position;

  while (start > 0 && '\x00\r\n\x85\u2028\u2029'.indexOf(this.buffer.charAt(start - 1)) === -1) {
    start -= 1;
    if (this.position - start > (maxLength / 2 - 1)) {
      head = ' ... ';
      start += 5;
      break;
    }
  }

  tail = '';
  end = this.position;

  while (end < this.buffer.length && '\x00\r\n\x85\u2028\u2029'.indexOf(this.buffer.charAt(end)) === -1) {
    end += 1;
    if (end - this.position > (maxLength / 2 - 1)) {
      tail = ' ... ';
      end -= 5;
      break;
    }
  }

  snippet = this.buffer.slice(start, end);

  return common.repeat(' ', indent) + head + snippet + tail + '\n' +
         common.repeat(' ', indent + this.position - start + head.length) + '^';
};


Mark.prototype.toString = function toString(compact) {
  var snippet, where = '';

  if (this.name) {
    where += 'in "' + this.name + '" ';
  }

  where += 'at line ' + (this.line + 1) + ', column ' + (this.column + 1);

  if (!compact) {
    snippet = this.getSnippet();

    if (snippet) {
      where += ':\n' + snippet;
    }
  }

  return where;
};


module.exports = Mark;

},{"./common":36}],41:[function(require,module,exports){
'use strict';

/*eslint-disable max-len*/

var common        = require('./common');
var YAMLException = require('./exception');
var Type          = require('./type');


function compileList(schema, name, result) {
  var exclude = [];

  schema.include.forEach(function (includedSchema) {
    result = compileList(includedSchema, name, result);
  });

  schema[name].forEach(function (currentType) {
    result.forEach(function (previousType, previousIndex) {
      if (previousType.tag === currentType.tag && previousType.kind === currentType.kind) {
        exclude.push(previousIndex);
      }
    });

    result.push(currentType);
  });

  return result.filter(function (type, index) {
    return exclude.indexOf(index) === -1;
  });
}


function compileMap(/* lists... */) {
  var result = {
        scalar: {},
        sequence: {},
        mapping: {},
        fallback: {}
      }, index, length;

  function collectType(type) {
    result[type.kind][type.tag] = result['fallback'][type.tag] = type;
  }

  for (index = 0, length = arguments.length; index < length; index += 1) {
    arguments[index].forEach(collectType);
  }
  return result;
}


function Schema(definition) {
  this.include  = definition.include  || [];
  this.implicit = definition.implicit || [];
  this.explicit = definition.explicit || [];

  this.implicit.forEach(function (type) {
    if (type.loadKind && type.loadKind !== 'scalar') {
      throw new YAMLException('There is a non-scalar type in the implicit list of a schema. Implicit resolving of such types is not supported.');
    }
  });

  this.compiledImplicit = compileList(this, 'implicit', []);
  this.compiledExplicit = compileList(this, 'explicit', []);
  this.compiledTypeMap  = compileMap(this.compiledImplicit, this.compiledExplicit);
}


Schema.DEFAULT = null;


Schema.create = function createSchema() {
  var schemas, types;

  switch (arguments.length) {
    case 1:
      schemas = Schema.DEFAULT;
      types = arguments[0];
      break;

    case 2:
      schemas = arguments[0];
      types = arguments[1];
      break;

    default:
      throw new YAMLException('Wrong number of arguments for Schema.create function');
  }

  schemas = common.toArray(schemas);
  types = common.toArray(types);

  if (!schemas.every(function (schema) { return schema instanceof Schema; })) {
    throw new YAMLException('Specified list of super schemas (or a single Schema object) contains a non-Schema object.');
  }

  if (!types.every(function (type) { return type instanceof Type; })) {
    throw new YAMLException('Specified list of YAML types (or a single Type object) contains a non-Type object.');
  }

  return new Schema({
    include: schemas,
    explicit: types
  });
};


module.exports = Schema;

},{"./common":36,"./exception":38,"./type":47}],42:[function(require,module,exports){
// Standard YAML's Core schema.
// http://www.yaml.org/spec/1.2/spec.html#id2804923
//
// NOTE: JS-YAML does not support schema-specific tag resolution restrictions.
// So, Core schema has no distinctions from JSON schema is JS-YAML.


'use strict';


var Schema = require('../schema');


module.exports = new Schema({
  include: [
    require('./json')
  ]
});

},{"../schema":41,"./json":46}],43:[function(require,module,exports){
// JS-YAML's default schema for `load` function.
// It is not described in the YAML specification.
//
// This schema is based on JS-YAML's default safe schema and includes
// JavaScript-specific types: !!js/undefined, !!js/regexp and !!js/function.
//
// Also this schema is used as default base schema at `Schema.create` function.


'use strict';


var Schema = require('../schema');


module.exports = Schema.DEFAULT = new Schema({
  include: [
    require('./default_safe')
  ],
  explicit: [
    require('../type/js/undefined'),
    require('../type/js/regexp'),
    require('../type/js/function')
  ]
});

},{"../schema":41,"../type/js/function":52,"../type/js/regexp":53,"../type/js/undefined":54,"./default_safe":44}],44:[function(require,module,exports){
// JS-YAML's default schema for `safeLoad` function.
// It is not described in the YAML specification.
//
// This schema is based on standard YAML's Core schema and includes most of
// extra types described at YAML tag repository. (http://yaml.org/type/)


'use strict';


var Schema = require('../schema');


module.exports = new Schema({
  include: [
    require('./core')
  ],
  implicit: [
    require('../type/timestamp'),
    require('../type/merge')
  ],
  explicit: [
    require('../type/binary'),
    require('../type/omap'),
    require('../type/pairs'),
    require('../type/set')
  ]
});

},{"../schema":41,"../type/binary":48,"../type/merge":56,"../type/omap":58,"../type/pairs":59,"../type/set":61,"../type/timestamp":63,"./core":42}],45:[function(require,module,exports){
// Standard YAML's Failsafe schema.
// http://www.yaml.org/spec/1.2/spec.html#id2802346


'use strict';


var Schema = require('../schema');


module.exports = new Schema({
  explicit: [
    require('../type/str'),
    require('../type/seq'),
    require('../type/map')
  ]
});

},{"../schema":41,"../type/map":55,"../type/seq":60,"../type/str":62}],46:[function(require,module,exports){
// Standard YAML's JSON schema.
// http://www.yaml.org/spec/1.2/spec.html#id2803231
//
// NOTE: JS-YAML does not support schema-specific tag resolution restrictions.
// So, this schema is not such strict as defined in the YAML specification.
// It allows numbers in binary notaion, use `Null` and `NULL` as `null`, etc.


'use strict';


var Schema = require('../schema');


module.exports = new Schema({
  include: [
    require('./failsafe')
  ],
  implicit: [
    require('../type/null'),
    require('../type/bool'),
    require('../type/int'),
    require('../type/float')
  ]
});

},{"../schema":41,"../type/bool":49,"../type/float":50,"../type/int":51,"../type/null":57,"./failsafe":45}],47:[function(require,module,exports){
'use strict';

var YAMLException = require('./exception');

var TYPE_CONSTRUCTOR_OPTIONS = [
  'kind',
  'resolve',
  'construct',
  'instanceOf',
  'predicate',
  'represent',
  'defaultStyle',
  'styleAliases'
];

var YAML_NODE_KINDS = [
  'scalar',
  'sequence',
  'mapping'
];

function compileStyleAliases(map) {
  var result = {};

  if (map !== null) {
    Object.keys(map).forEach(function (style) {
      map[style].forEach(function (alias) {
        result[String(alias)] = style;
      });
    });
  }

  return result;
}

function Type(tag, options) {
  options = options || {};

  Object.keys(options).forEach(function (name) {
    if (TYPE_CONSTRUCTOR_OPTIONS.indexOf(name) === -1) {
      throw new YAMLException('Unknown option "' + name + '" is met in definition of "' + tag + '" YAML type.');
    }
  });

  // TODO: Add tag format check.
  this.tag          = tag;
  this.kind         = options['kind']         || null;
  this.resolve      = options['resolve']      || function () { return true; };
  this.construct    = options['construct']    || function (data) { return data; };
  this.instanceOf   = options['instanceOf']   || null;
  this.predicate    = options['predicate']    || null;
  this.represent    = options['represent']    || null;
  this.defaultStyle = options['defaultStyle'] || null;
  this.styleAliases = compileStyleAliases(options['styleAliases'] || null);

  if (YAML_NODE_KINDS.indexOf(this.kind) === -1) {
    throw new YAMLException('Unknown kind "' + this.kind + '" is specified for "' + tag + '" YAML type.');
  }
}

module.exports = Type;

},{"./exception":38}],48:[function(require,module,exports){
'use strict';

/*eslint-disable no-bitwise*/

var NodeBuffer;

try {
  // A trick for browserified version, to not include `Buffer` shim
  var _require = require;
  NodeBuffer = _require('buffer').Buffer;
} catch (__) {}

var Type       = require('../type');


// [ 64, 65, 66 ] -> [ padding, CR, LF ]
var BASE64_MAP = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n\r';


function resolveYamlBinary(data) {
  if (data === null) return false;

  var code, idx, bitlen = 0, max = data.length, map = BASE64_MAP;

  // Convert one by one.
  for (idx = 0; idx < max; idx++) {
    code = map.indexOf(data.charAt(idx));

    // Skip CR/LF
    if (code > 64) continue;

    // Fail on illegal characters
    if (code < 0) return false;

    bitlen += 6;
  }

  // If there are any bits left, source was corrupted
  return (bitlen % 8) === 0;
}

function constructYamlBinary(data) {
  var idx, tailbits,
      input = data.replace(/[\r\n=]/g, ''), // remove CR/LF & padding to simplify scan
      max = input.length,
      map = BASE64_MAP,
      bits = 0,
      result = [];

  // Collect by 6*4 bits (3 bytes)

  for (idx = 0; idx < max; idx++) {
    if ((idx % 4 === 0) && idx) {
      result.push((bits >> 16) & 0xFF);
      result.push((bits >> 8) & 0xFF);
      result.push(bits & 0xFF);
    }

    bits = (bits << 6) | map.indexOf(input.charAt(idx));
  }

  // Dump tail

  tailbits = (max % 4) * 6;

  if (tailbits === 0) {
    result.push((bits >> 16) & 0xFF);
    result.push((bits >> 8) & 0xFF);
    result.push(bits & 0xFF);
  } else if (tailbits === 18) {
    result.push((bits >> 10) & 0xFF);
    result.push((bits >> 2) & 0xFF);
  } else if (tailbits === 12) {
    result.push((bits >> 4) & 0xFF);
  }

  // Wrap into Buffer for NodeJS and leave Array for browser
  if (NodeBuffer) {
    // Support node 6.+ Buffer API when available
    return NodeBuffer.from ? NodeBuffer.from(result) : new NodeBuffer(result);
  }

  return result;
}

function representYamlBinary(object /*, style*/) {
  var result = '', bits = 0, idx, tail,
      max = object.length,
      map = BASE64_MAP;

  // Convert every three bytes to 4 ASCII characters.

  for (idx = 0; idx < max; idx++) {
    if ((idx % 3 === 0) && idx) {
      result += map[(bits >> 18) & 0x3F];
      result += map[(bits >> 12) & 0x3F];
      result += map[(bits >> 6) & 0x3F];
      result += map[bits & 0x3F];
    }

    bits = (bits << 8) + object[idx];
  }

  // Dump tail

  tail = max % 3;

  if (tail === 0) {
    result += map[(bits >> 18) & 0x3F];
    result += map[(bits >> 12) & 0x3F];
    result += map[(bits >> 6) & 0x3F];
    result += map[bits & 0x3F];
  } else if (tail === 2) {
    result += map[(bits >> 10) & 0x3F];
    result += map[(bits >> 4) & 0x3F];
    result += map[(bits << 2) & 0x3F];
    result += map[64];
  } else if (tail === 1) {
    result += map[(bits >> 2) & 0x3F];
    result += map[(bits << 4) & 0x3F];
    result += map[64];
    result += map[64];
  }

  return result;
}

function isBinary(object) {
  return NodeBuffer && NodeBuffer.isBuffer(object);
}

module.exports = new Type('tag:yaml.org,2002:binary', {
  kind: 'scalar',
  resolve: resolveYamlBinary,
  construct: constructYamlBinary,
  predicate: isBinary,
  represent: representYamlBinary
});

},{"../type":47}],49:[function(require,module,exports){
'use strict';

var Type = require('../type');

function resolveYamlBoolean(data) {
  if (data === null) return false;

  var max = data.length;

  return (max === 4 && (data === 'true' || data === 'True' || data === 'TRUE')) ||
         (max === 5 && (data === 'false' || data === 'False' || data === 'FALSE'));
}

function constructYamlBoolean(data) {
  return data === 'true' ||
         data === 'True' ||
         data === 'TRUE';
}

function isBoolean(object) {
  return Object.prototype.toString.call(object) === '[object Boolean]';
}

module.exports = new Type('tag:yaml.org,2002:bool', {
  kind: 'scalar',
  resolve: resolveYamlBoolean,
  construct: constructYamlBoolean,
  predicate: isBoolean,
  represent: {
    lowercase: function (object) { return object ? 'true' : 'false'; },
    uppercase: function (object) { return object ? 'TRUE' : 'FALSE'; },
    camelcase: function (object) { return object ? 'True' : 'False'; }
  },
  defaultStyle: 'lowercase'
});

},{"../type":47}],50:[function(require,module,exports){
'use strict';

var common = require('../common');
var Type   = require('../type');

var YAML_FLOAT_PATTERN = new RegExp(
  // 2.5e4, 2.5 and integers
  '^(?:[-+]?(?:0|[1-9][0-9_]*)(?:\\.[0-9_]*)?(?:[eE][-+]?[0-9]+)?' +
  // .2e4, .2
  // special case, seems not from spec
  '|\\.[0-9_]+(?:[eE][-+]?[0-9]+)?' +
  // 20:59
  '|[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+\\.[0-9_]*' +
  // .inf
  '|[-+]?\\.(?:inf|Inf|INF)' +
  // .nan
  '|\\.(?:nan|NaN|NAN))$');

function resolveYamlFloat(data) {
  if (data === null) return false;

  if (!YAML_FLOAT_PATTERN.test(data) ||
      // Quick hack to not allow integers end with `_`
      // Probably should update regexp & check speed
      data[data.length - 1] === '_') {
    return false;
  }

  return true;
}

function constructYamlFloat(data) {
  var value, sign, base, digits;

  value  = data.replace(/_/g, '').toLowerCase();
  sign   = value[0] === '-' ? -1 : 1;
  digits = [];

  if ('+-'.indexOf(value[0]) >= 0) {
    value = value.slice(1);
  }

  if (value === '.inf') {
    return (sign === 1) ? Number.POSITIVE_INFINITY : Number.NEGATIVE_INFINITY;

  } else if (value === '.nan') {
    return NaN;

  } else if (value.indexOf(':') >= 0) {
    value.split(':').forEach(function (v) {
      digits.unshift(parseFloat(v, 10));
    });

    value = 0.0;
    base = 1;

    digits.forEach(function (d) {
      value += d * base;
      base *= 60;
    });

    return sign * value;

  }
  return sign * parseFloat(value, 10);
}


var SCIENTIFIC_WITHOUT_DOT = /^[-+]?[0-9]+e/;

function representYamlFloat(object, style) {
  var res;

  if (isNaN(object)) {
    switch (style) {
      case 'lowercase': return '.nan';
      case 'uppercase': return '.NAN';
      case 'camelcase': return '.NaN';
    }
  } else if (Number.POSITIVE_INFINITY === object) {
    switch (style) {
      case 'lowercase': return '.inf';
      case 'uppercase': return '.INF';
      case 'camelcase': return '.Inf';
    }
  } else if (Number.NEGATIVE_INFINITY === object) {
    switch (style) {
      case 'lowercase': return '-.inf';
      case 'uppercase': return '-.INF';
      case 'camelcase': return '-.Inf';
    }
  } else if (common.isNegativeZero(object)) {
    return '-0.0';
  }

  res = object.toString(10);

  // JS stringifier can build scientific format without dots: 5e-100,
  // while YAML requres dot: 5.e-100. Fix it with simple hack

  return SCIENTIFIC_WITHOUT_DOT.test(res) ? res.replace('e', '.e') : res;
}

function isFloat(object) {
  return (Object.prototype.toString.call(object) === '[object Number]') &&
         (object % 1 !== 0 || common.isNegativeZero(object));
}

module.exports = new Type('tag:yaml.org,2002:float', {
  kind: 'scalar',
  resolve: resolveYamlFloat,
  construct: constructYamlFloat,
  predicate: isFloat,
  represent: representYamlFloat,
  defaultStyle: 'lowercase'
});

},{"../common":36,"../type":47}],51:[function(require,module,exports){
'use strict';

var common = require('../common');
var Type   = require('../type');

function isHexCode(c) {
  return ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) ||
         ((0x41/* A */ <= c) && (c <= 0x46/* F */)) ||
         ((0x61/* a */ <= c) && (c <= 0x66/* f */));
}

function isOctCode(c) {
  return ((0x30/* 0 */ <= c) && (c <= 0x37/* 7 */));
}

function isDecCode(c) {
  return ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */));
}

function resolveYamlInteger(data) {
  if (data === null) return false;

  var max = data.length,
      index = 0,
      hasDigits = false,
      ch;

  if (!max) return false;

  ch = data[index];

  // sign
  if (ch === '-' || ch === '+') {
    ch = data[++index];
  }

  if (ch === '0') {
    // 0
    if (index + 1 === max) return true;
    ch = data[++index];

    // base 2, base 8, base 16

    if (ch === 'b') {
      // base 2
      index++;

      for (; index < max; index++) {
        ch = data[index];
        if (ch === '_') continue;
        if (ch !== '0' && ch !== '1') return false;
        hasDigits = true;
      }
      return hasDigits && ch !== '_';
    }


    if (ch === 'x') {
      // base 16
      index++;

      for (; index < max; index++) {
        ch = data[index];
        if (ch === '_') continue;
        if (!isHexCode(data.charCodeAt(index))) return false;
        hasDigits = true;
      }
      return hasDigits && ch !== '_';
    }

    // base 8
    for (; index < max; index++) {
      ch = data[index];
      if (ch === '_') continue;
      if (!isOctCode(data.charCodeAt(index))) return false;
      hasDigits = true;
    }
    return hasDigits && ch !== '_';
  }

  // base 10 (except 0) or base 60

  // value should not start with `_`;
  if (ch === '_') return false;

  for (; index < max; index++) {
    ch = data[index];
    if (ch === '_') continue;
    if (ch === ':') break;
    if (!isDecCode(data.charCodeAt(index))) {
      return false;
    }
    hasDigits = true;
  }

  // Should have digits and should not end with `_`
  if (!hasDigits || ch === '_') return false;

  // if !base60 - done;
  if (ch !== ':') return true;

  // base60 almost not used, no needs to optimize
  return /^(:[0-5]?[0-9])+$/.test(data.slice(index));
}

function constructYamlInteger(data) {
  var value = data, sign = 1, ch, base, digits = [];

  if (value.indexOf('_') !== -1) {
    value = value.replace(/_/g, '');
  }

  ch = value[0];

  if (ch === '-' || ch === '+') {
    if (ch === '-') sign = -1;
    value = value.slice(1);
    ch = value[0];
  }

  if (value === '0') return 0;

  if (ch === '0') {
    if (value[1] === 'b') return sign * parseInt(value.slice(2), 2);
    if (value[1] === 'x') return sign * parseInt(value, 16);
    return sign * parseInt(value, 8);
  }

  if (value.indexOf(':') !== -1) {
    value.split(':').forEach(function (v) {
      digits.unshift(parseInt(v, 10));
    });

    value = 0;
    base = 1;

    digits.forEach(function (d) {
      value += (d * base);
      base *= 60;
    });

    return sign * value;

  }

  return sign * parseInt(value, 10);
}

function isInteger(object) {
  return (Object.prototype.toString.call(object)) === '[object Number]' &&
         (object % 1 === 0 && !common.isNegativeZero(object));
}

module.exports = new Type('tag:yaml.org,2002:int', {
  kind: 'scalar',
  resolve: resolveYamlInteger,
  construct: constructYamlInteger,
  predicate: isInteger,
  represent: {
    binary:      function (obj) { return obj >= 0 ? '0b' + obj.toString(2) : '-0b' + obj.toString(2).slice(1); },
    octal:       function (obj) { return obj >= 0 ? '0'  + obj.toString(8) : '-0'  + obj.toString(8).slice(1); },
    decimal:     function (obj) { return obj.toString(10); },
    /* eslint-disable max-len */
    hexadecimal: function (obj) { return obj >= 0 ? '0x' + obj.toString(16).toUpperCase() :  '-0x' + obj.toString(16).toUpperCase().slice(1); }
  },
  defaultStyle: 'decimal',
  styleAliases: {
    binary:      [ 2,  'bin' ],
    octal:       [ 8,  'oct' ],
    decimal:     [ 10, 'dec' ],
    hexadecimal: [ 16, 'hex' ]
  }
});

},{"../common":36,"../type":47}],52:[function(require,module,exports){
'use strict';

var esprima;

// Browserified version does not have esprima
//
// 1. For node.js just require module as deps
// 2. For browser try to require mudule via external AMD system.
//    If not found - try to fallback to window.esprima. If not
//    found too - then fail to parse.
//
try {
  // workaround to exclude package from browserify list.
  var _require = require;
  esprima = _require('esprima');
} catch (_) {
  /*global window */
  if (typeof window !== 'undefined') esprima = window.esprima;
}

var Type = require('../../type');

function resolveJavascriptFunction(data) {
  if (data === null) return false;

  try {
    var source = '(' + data + ')',
        ast    = esprima.parse(source, { range: true });

    if (ast.type                    !== 'Program'             ||
        ast.body.length             !== 1                     ||
        ast.body[0].type            !== 'ExpressionStatement' ||
        (ast.body[0].expression.type !== 'ArrowFunctionExpression' &&
          ast.body[0].expression.type !== 'FunctionExpression')) {
      return false;
    }

    return true;
  } catch (err) {
    return false;
  }
}

function constructJavascriptFunction(data) {
  /*jslint evil:true*/

  var source = '(' + data + ')',
      ast    = esprima.parse(source, { range: true }),
      params = [],
      body;

  if (ast.type                    !== 'Program'             ||
      ast.body.length             !== 1                     ||
      ast.body[0].type            !== 'ExpressionStatement' ||
      (ast.body[0].expression.type !== 'ArrowFunctionExpression' &&
        ast.body[0].expression.type !== 'FunctionExpression')) {
    throw new Error('Failed to resolve function');
  }

  ast.body[0].expression.params.forEach(function (param) {
    params.push(param.name);
  });

  body = ast.body[0].expression.body.range;

  // Esprima's ranges include the first '{' and the last '}' characters on
  // function expressions. So cut them out.
  if (ast.body[0].expression.body.type === 'BlockStatement') {
    /*eslint-disable no-new-func*/
    return new Function(params, source.slice(body[0] + 1, body[1] - 1));
  }
  // ES6 arrow functions can omit the BlockStatement. In that case, just return
  // the body.
  /*eslint-disable no-new-func*/
  return new Function(params, 'return ' + source.slice(body[0], body[1]));
}

function representJavascriptFunction(object /*, style*/) {
  return object.toString();
}

function isFunction(object) {
  return Object.prototype.toString.call(object) === '[object Function]';
}

module.exports = new Type('tag:yaml.org,2002:js/function', {
  kind: 'scalar',
  resolve: resolveJavascriptFunction,
  construct: constructJavascriptFunction,
  predicate: isFunction,
  represent: representJavascriptFunction
});

},{"../../type":47}],53:[function(require,module,exports){
'use strict';

var Type = require('../../type');

function resolveJavascriptRegExp(data) {
  if (data === null) return false;
  if (data.length === 0) return false;

  var regexp = data,
      tail   = /\/([gim]*)$/.exec(data),
      modifiers = '';

  // if regexp starts with '/' it can have modifiers and must be properly closed
  // `/foo/gim` - modifiers tail can be maximum 3 chars
  if (regexp[0] === '/') {
    if (tail) modifiers = tail[1];

    if (modifiers.length > 3) return false;
    // if expression starts with /, is should be properly terminated
    if (regexp[regexp.length - modifiers.length - 1] !== '/') return false;
  }

  return true;
}

function constructJavascriptRegExp(data) {
  var regexp = data,
      tail   = /\/([gim]*)$/.exec(data),
      modifiers = '';

  // `/foo/gim` - tail can be maximum 4 chars
  if (regexp[0] === '/') {
    if (tail) modifiers = tail[1];
    regexp = regexp.slice(1, regexp.length - modifiers.length - 1);
  }

  return new RegExp(regexp, modifiers);
}

function representJavascriptRegExp(object /*, style*/) {
  var result = '/' + object.source + '/';

  if (object.global) result += 'g';
  if (object.multiline) result += 'm';
  if (object.ignoreCase) result += 'i';

  return result;
}

function isRegExp(object) {
  return Object.prototype.toString.call(object) === '[object RegExp]';
}

module.exports = new Type('tag:yaml.org,2002:js/regexp', {
  kind: 'scalar',
  resolve: resolveJavascriptRegExp,
  construct: constructJavascriptRegExp,
  predicate: isRegExp,
  represent: representJavascriptRegExp
});

},{"../../type":47}],54:[function(require,module,exports){
'use strict';

var Type = require('../../type');

function resolveJavascriptUndefined() {
  return true;
}

function constructJavascriptUndefined() {
  /*eslint-disable no-undefined*/
  return undefined;
}

function representJavascriptUndefined() {
  return '';
}

function isUndefined(object) {
  return typeof object === 'undefined';
}

module.exports = new Type('tag:yaml.org,2002:js/undefined', {
  kind: 'scalar',
  resolve: resolveJavascriptUndefined,
  construct: constructJavascriptUndefined,
  predicate: isUndefined,
  represent: representJavascriptUndefined
});

},{"../../type":47}],55:[function(require,module,exports){
'use strict';

var Type = require('../type');

module.exports = new Type('tag:yaml.org,2002:map', {
  kind: 'mapping',
  construct: function (data) { return data !== null ? data : {}; }
});

},{"../type":47}],56:[function(require,module,exports){
'use strict';

var Type = require('../type');

function resolveYamlMerge(data) {
  return data === '<<' || data === null;
}

module.exports = new Type('tag:yaml.org,2002:merge', {
  kind: 'scalar',
  resolve: resolveYamlMerge
});

},{"../type":47}],57:[function(require,module,exports){
'use strict';

var Type = require('../type');

function resolveYamlNull(data) {
  if (data === null) return true;

  var max = data.length;

  return (max === 1 && data === '~') ||
         (max === 4 && (data === 'null' || data === 'Null' || data === 'NULL'));
}

function constructYamlNull() {
  return null;
}

function isNull(object) {
  return object === null;
}

module.exports = new Type('tag:yaml.org,2002:null', {
  kind: 'scalar',
  resolve: resolveYamlNull,
  construct: constructYamlNull,
  predicate: isNull,
  represent: {
    canonical: function () { return '~';    },
    lowercase: function () { return 'null'; },
    uppercase: function () { return 'NULL'; },
    camelcase: function () { return 'Null'; }
  },
  defaultStyle: 'lowercase'
});

},{"../type":47}],58:[function(require,module,exports){
'use strict';

var Type = require('../type');

var _hasOwnProperty = Object.prototype.hasOwnProperty;
var _toString       = Object.prototype.toString;

function resolveYamlOmap(data) {
  if (data === null) return true;

  var objectKeys = [], index, length, pair, pairKey, pairHasKey,
      object = data;

  for (index = 0, length = object.length; index < length; index += 1) {
    pair = object[index];
    pairHasKey = false;

    if (_toString.call(pair) !== '[object Object]') return false;

    for (pairKey in pair) {
      if (_hasOwnProperty.call(pair, pairKey)) {
        if (!pairHasKey) pairHasKey = true;
        else return false;
      }
    }

    if (!pairHasKey) return false;

    if (objectKeys.indexOf(pairKey) === -1) objectKeys.push(pairKey);
    else return false;
  }

  return true;
}

function constructYamlOmap(data) {
  return data !== null ? data : [];
}

module.exports = new Type('tag:yaml.org,2002:omap', {
  kind: 'sequence',
  resolve: resolveYamlOmap,
  construct: constructYamlOmap
});

},{"../type":47}],59:[function(require,module,exports){
'use strict';

var Type = require('../type');

var _toString = Object.prototype.toString;

function resolveYamlPairs(data) {
  if (data === null) return true;

  var index, length, pair, keys, result,
      object = data;

  result = new Array(object.length);

  for (index = 0, length = object.length; index < length; index += 1) {
    pair = object[index];

    if (_toString.call(pair) !== '[object Object]') return false;

    keys = Object.keys(pair);

    if (keys.length !== 1) return false;

    result[index] = [ keys[0], pair[keys[0]] ];
  }

  return true;
}

function constructYamlPairs(data) {
  if (data === null) return [];

  var index, length, pair, keys, result,
      object = data;

  result = new Array(object.length);

  for (index = 0, length = object.length; index < length; index += 1) {
    pair = object[index];

    keys = Object.keys(pair);

    result[index] = [ keys[0], pair[keys[0]] ];
  }

  return result;
}

module.exports = new Type('tag:yaml.org,2002:pairs', {
  kind: 'sequence',
  resolve: resolveYamlPairs,
  construct: constructYamlPairs
});

},{"../type":47}],60:[function(require,module,exports){
'use strict';

var Type = require('../type');

module.exports = new Type('tag:yaml.org,2002:seq', {
  kind: 'sequence',
  construct: function (data) { return data !== null ? data : []; }
});

},{"../type":47}],61:[function(require,module,exports){
'use strict';

var Type = require('../type');

var _hasOwnProperty = Object.prototype.hasOwnProperty;

function resolveYamlSet(data) {
  if (data === null) return true;

  var key, object = data;

  for (key in object) {
    if (_hasOwnProperty.call(object, key)) {
      if (object[key] !== null) return false;
    }
  }

  return true;
}

function constructYamlSet(data) {
  return data !== null ? data : {};
}

module.exports = new Type('tag:yaml.org,2002:set', {
  kind: 'mapping',
  resolve: resolveYamlSet,
  construct: constructYamlSet
});

},{"../type":47}],62:[function(require,module,exports){
'use strict';

var Type = require('../type');

module.exports = new Type('tag:yaml.org,2002:str', {
  kind: 'scalar',
  construct: function (data) { return data !== null ? data : ''; }
});

},{"../type":47}],63:[function(require,module,exports){
'use strict';

var Type = require('../type');

var YAML_DATE_REGEXP = new RegExp(
  '^([0-9][0-9][0-9][0-9])'          + // [1] year
  '-([0-9][0-9])'                    + // [2] month
  '-([0-9][0-9])$');                   // [3] day

var YAML_TIMESTAMP_REGEXP = new RegExp(
  '^([0-9][0-9][0-9][0-9])'          + // [1] year
  '-([0-9][0-9]?)'                   + // [2] month
  '-([0-9][0-9]?)'                   + // [3] day
  '(?:[Tt]|[ \\t]+)'                 + // ...
  '([0-9][0-9]?)'                    + // [4] hour
  ':([0-9][0-9])'                    + // [5] minute
  ':([0-9][0-9])'                    + // [6] second
  '(?:\\.([0-9]*))?'                 + // [7] fraction
  '(?:[ \\t]*(Z|([-+])([0-9][0-9]?)' + // [8] tz [9] tz_sign [10] tz_hour
  '(?::([0-9][0-9]))?))?$');           // [11] tz_minute

function resolveYamlTimestamp(data) {
  if (data === null) return false;
  if (YAML_DATE_REGEXP.exec(data) !== null) return true;
  if (YAML_TIMESTAMP_REGEXP.exec(data) !== null) return true;
  return false;
}

function constructYamlTimestamp(data) {
  var match, year, month, day, hour, minute, second, fraction = 0,
      delta = null, tz_hour, tz_minute, date;

  match = YAML_DATE_REGEXP.exec(data);
  if (match === null) match = YAML_TIMESTAMP_REGEXP.exec(data);

  if (match === null) throw new Error('Date resolve error');

  // match: [1] year [2] month [3] day

  year = +(match[1]);
  month = +(match[2]) - 1; // JS month starts with 0
  day = +(match[3]);

  if (!match[4]) { // no hour
    return new Date(Date.UTC(year, month, day));
  }

  // match: [4] hour [5] minute [6] second [7] fraction

  hour = +(match[4]);
  minute = +(match[5]);
  second = +(match[6]);

  if (match[7]) {
    fraction = match[7].slice(0, 3);
    while (fraction.length < 3) { // milli-seconds
      fraction += '0';
    }
    fraction = +fraction;
  }

  // match: [8] tz [9] tz_sign [10] tz_hour [11] tz_minute

  if (match[9]) {
    tz_hour = +(match[10]);
    tz_minute = +(match[11] || 0);
    delta = (tz_hour * 60 + tz_minute) * 60000; // delta in mili-seconds
    if (match[9] === '-') delta = -delta;
  }

  date = new Date(Date.UTC(year, month, day, hour, minute, second, fraction));

  if (delta) date.setTime(date.getTime() - delta);

  return date;
}

function representYamlTimestamp(object /*, style*/) {
  return object.toISOString();
}

module.exports = new Type('tag:yaml.org,2002:timestamp', {
  kind: 'scalar',
  resolve: resolveYamlTimestamp,
  construct: constructYamlTimestamp,
  instanceOf: Date,
  represent: representYamlTimestamp
});

},{"../type":47}],64:[function(require,module,exports){
"use strict";

var format = require("format-util");
var slice = Array.prototype.slice;
var protectedProperties = ["name", "message", "stack"];
var errorPrototypeProperties = [
  "name", "message", "description", "number", "code", "fileName", "lineNumber", "columnNumber",
  "sourceURL", "line", "column", "stack"
];

module.exports = create(Error);
module.exports.error = create(Error);
module.exports.eval = create(EvalError);
module.exports.range = create(RangeError);
module.exports.reference = create(ReferenceError);
module.exports.syntax = create(SyntaxError);
module.exports.type = create(TypeError);
module.exports.uri = create(URIError);
module.exports.formatter = format;

/**
 * Creates a new {@link ono} function that creates the given Error class.
 *
 * @param {Class} Klass - The Error subclass to create
 * @returns {ono}
 */
function create (Klass) {
  /**
   * @param {Error}   [err]     - The original error, if any
   * @param {object}  [props]   - An object whose properties will be added to the error object
   * @param {string}  [message] - The error message. May contain {@link util#format} placeholders
   * @param {...*}    [params]  - Parameters that map to the `message` placeholders
   * @returns {Error}
   */
  return function onoFactory (err, props, message, params) {   // eslint-disable-line no-unused-vars
    var formatArgs = [];
    var formattedMessage = "";

    // Determine which arguments were actually specified
    if (typeof err === "string") {
      formatArgs = slice.call(arguments);
      err = props = undefined;
    }
    else if (typeof props === "string") {
      formatArgs = slice.call(arguments, 1);
      props = undefined;
    }
    else if (typeof message === "string") {
      formatArgs = slice.call(arguments, 2);
    }

    // If there are any format arguments, then format the error message
    if (formatArgs.length > 0) {
      formattedMessage = module.exports.formatter.apply(null, formatArgs);
    }

    if (err && err.message) {
      // The inner-error's message will be added to the new message
      formattedMessage += (formattedMessage ? " \n" : "") + err.message;
    }

    // Create the new error
    // NOTE: DON'T move this to a separate function! We don't want to pollute the stack trace
    var newError = new Klass(formattedMessage);

    // Extend the new error with the additional properties
    extendError(newError, err);   // Copy properties of the original error
    extendToJSON(newError);       // Replace the original toJSON method
    extend(newError, props);      // Copy custom properties, possibly including a custom toJSON method

    return newError;
  };
}

/**
 * Extends the targetError with the properties of the source error.
 *
 * @param {Error}   targetError - The error object to extend
 * @param {?Error}  sourceError - The source error object, if any
 */
function extendError (targetError, sourceError) {
  extendStack(targetError, sourceError);
  extend(targetError, sourceError);
}

/**
 * JavaScript engines differ in how errors are serialized to JSON - especially when it comes
 * to custom error properties and stack traces.  So we add our own toJSON method that ALWAYS
 * outputs every property of the error.
 */
function extendToJSON (error) {
  error.toJSON = errorToJSON;

  // Also add an inspect() method, for compatibility with Node.js' `util.inspect()` method
  error.inspect = errorToString;
}

/**
 * Extends the target object with the properties of the source object.
 *
 * @param {object}  target - The object to extend
 * @param {?source} source - The object whose properties are copied
 */
function extend (target, source) {
  if (source && typeof source === "object") {
    var keys = Object.keys(source);
    for (var i = 0; i < keys.length; i++) {
      var key = keys[i];

      // Don't copy "protected" properties, since they have special meaning/behavior
      // and are set by the onoFactory function
      if (protectedProperties.indexOf(key) >= 0) {
        continue;
      }

      try {
        target[key] = source[key];
      }
      catch (e) {
        // This property is read-only, so it can't be copied
      }
    }
  }
}

/**
 * Custom JSON serializer for Error objects.
 * Returns all built-in error properties, as well as extended properties.
 *
 * @returns {object}
 */
function errorToJSON () {
  var json = {};

  // Get all the properties of this error
  var keys = Object.keys(this);

  // Also include properties from the Error prototype
  keys = keys.concat(errorPrototypeProperties);

  for (var i = 0; i < keys.length; i++) {
    var key = keys[i];
    var value = this[key];
    var type = typeof value;
    if (type !== "undefined" && type !== "function") {
      json[key] = value;
    }
  }

  return json;
}

/**
 * Serializes Error objects as human-readable JSON strings for debugging/logging purposes.
 *
 * @returns {string}
 */
function errorToString () {
  return JSON.stringify(this, null, 2).replace(/\\n/g, "\n");
}

/**
 * Extend the error stack to include its cause
 *
 * @param {Error} targetError
 * @param {Error} sourceError
 */
function extendStack (targetError, sourceError) {
  if (hasLazyStack(targetError)) {
    if (sourceError) {
      lazyJoinStacks(targetError, sourceError);
    }
    else {
      lazyPopStack(targetError);
    }
  }
  else {
    if (sourceError) {
      targetError.stack = joinStacks(targetError.stack, sourceError.stack);
    }
    else {
      targetError.stack = popStack(targetError.stack);
    }
  }
}

/**
 * Appends the original {@link Error#stack} property to the new Error's stack.
 *
 * @param {string} newStack
 * @param {string} originalStack
 * @returns {string}
 */
function joinStacks (newStack, originalStack) {
  newStack = popStack(newStack);

  if (newStack && originalStack) {
    return newStack + "\n\n" + originalStack;
  }
  else {
    return newStack || originalStack;
  }
}

/**
 * Removes Ono from the stack, so that the stack starts at the original error location
 *
 * @param {string} stack
 * @returns {string}
 */
function popStack (stack) {
  if (stack) {
    var lines = stack.split("\n");

    if (lines.length < 2) {
      // The stack only has one line, so there's nothing we can remove
      return stack;
    }

    // Find the `onoFactory` call in the stack, and remove it
    for (var i = 0; i < lines.length; i++) {
      var line = lines[i];
      if (line.indexOf("onoFactory") >= 0) {
        lines.splice(i, 1);
        return lines.join("\n");
      }
    }

    // If we get here, then the stack doesn't contain a call to `onoFactory`.
    // This may be due to minification or some optimization of the JS engine.
    // So just return the stack as-is.
    return stack;
  }
}

/**
 * Does a one-time determination of whether this JavaScript engine
 * supports lazy `Error.stack` properties.
 */
var supportsLazyStack = (function () {
  return !!(
    // ES5 property descriptors must be supported
    Object.getOwnPropertyDescriptor && Object.defineProperty &&

    // Chrome on Android doesn't support lazy stacks :(
    (typeof navigator === "undefined" || !/Android/.test(navigator.userAgent))
  );
}());

/**
 * Does this error have a lazy stack property?
 *
 * @param {Error} err
 * @returns {boolean}
 */
function hasLazyStack (err) {
  if (!supportsLazyStack) {
    return false;
  }

  var descriptor = Object.getOwnPropertyDescriptor(err, "stack");
  if (!descriptor) {
    return false;
  }
  return typeof descriptor.get === "function";
}

/**
 * Calls {@link joinStacks} lazily, when the {@link Error#stack} property is accessed.
 *
 * @param {Error} targetError
 * @param {Error} sourceError
 */
function lazyJoinStacks (targetError, sourceError) {
  var targetStack = Object.getOwnPropertyDescriptor(targetError, "stack");

  Object.defineProperty(targetError, "stack", {
    get: function () {
      return joinStacks(targetStack.get.apply(targetError), sourceError.stack);
    },
    enumerable: false,
    configurable: true
  });
}

/**
 * Calls {@link popStack} lazily, when the {@link Error#stack} property is accessed.
 *
 * @param {Error} error
 */
function lazyPopStack (error) {
  var targetStack = Object.getOwnPropertyDescriptor(error, "stack");

  Object.defineProperty(error, "stack", {
    get: function () {
      return popStack(targetStack.get.apply(error));
    },
    enumerable: false,
    configurable: true
  });
}

},{"format-util":28}],65:[function(require,module,exports){
(function (process){
'use strict';

if (!process.version ||
    process.version.indexOf('v0.') === 0 ||
    process.version.indexOf('v1.') === 0 && process.version.indexOf('v1.8.') !== 0) {
  module.exports = { nextTick: nextTick };
} else {
  module.exports = process
}

function nextTick(fn, arg1, arg2, arg3) {
  if (typeof fn !== 'function') {
    throw new TypeError('"callback" argument must be a function');
  }
  var len = arguments.length;
  var args, i;
  switch (len) {
  case 0:
  case 1:
    return process.nextTick(fn);
  case 2:
    return process.nextTick(function afterTickOne() {
      fn.call(null, arg1);
    });
  case 3:
    return process.nextTick(function afterTickTwo() {
      fn.call(null, arg1, arg2);
    });
  case 4:
    return process.nextTick(function afterTickThree() {
      fn.call(null, arg1, arg2, arg3);
    });
  default:
    args = new Array(len - 1);
    i = 0;
    while (i < args.length) {
      args[i++] = arguments[i];
    }
    return process.nextTick(function afterTick() {
      fn.apply(null, args);
    });
  }
}


}).call(this,require('_process'))

},{"_process":66}],66:[function(require,module,exports){
// shim for using process in browser
var process = module.exports = {};

// cached from whatever global is present so that test runners that stub it
// don't break things.  But we need to wrap it in a try catch in case it is
// wrapped in strict mode code which doesn't define any globals.  It's inside a
// function because try/catches deoptimize in certain engines.

var cachedSetTimeout;
var cachedClearTimeout;

function defaultSetTimout() {
    throw new Error('setTimeout has not been defined');
}
function defaultClearTimeout () {
    throw new Error('clearTimeout has not been defined');
}
(function () {
    try {
        if (typeof setTimeout === 'function') {
            cachedSetTimeout = setTimeout;
        } else {
            cachedSetTimeout = defaultSetTimout;
        }
    } catch (e) {
        cachedSetTimeout = defaultSetTimout;
    }
    try {
        if (typeof clearTimeout === 'function') {
            cachedClearTimeout = clearTimeout;
        } else {
            cachedClearTimeout = defaultClearTimeout;
        }
    } catch (e) {
        cachedClearTimeout = defaultClearTimeout;
    }
} ())
function runTimeout(fun) {
    if (cachedSetTimeout === setTimeout) {
        //normal enviroments in sane situations
        return setTimeout(fun, 0);
    }
    // if setTimeout wasn't available but was latter defined
    if ((cachedSetTimeout === defaultSetTimout || !cachedSetTimeout) && setTimeout) {
        cachedSetTimeout = setTimeout;
        return setTimeout(fun, 0);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedSetTimeout(fun, 0);
    } catch(e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't trust the global object when called normally
            return cachedSetTimeout.call(null, fun, 0);
        } catch(e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error
            return cachedSetTimeout.call(this, fun, 0);
        }
    }


}
function runClearTimeout(marker) {
    if (cachedClearTimeout === clearTimeout) {
        //normal enviroments in sane situations
        return clearTimeout(marker);
    }
    // if clearTimeout wasn't available but was latter defined
    if ((cachedClearTimeout === defaultClearTimeout || !cachedClearTimeout) && clearTimeout) {
        cachedClearTimeout = clearTimeout;
        return clearTimeout(marker);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedClearTimeout(marker);
    } catch (e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't  trust the global object when called normally
            return cachedClearTimeout.call(null, marker);
        } catch (e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error.
            // Some versions of I.E. have different rules for clearTimeout vs setTimeout
            return cachedClearTimeout.call(this, marker);
        }
    }



}
var queue = [];
var draining = false;
var currentQueue;
var queueIndex = -1;

function cleanUpNextTick() {
    if (!draining || !currentQueue) {
        return;
    }
    draining = false;
    if (currentQueue.length) {
        queue = currentQueue.concat(queue);
    } else {
        queueIndex = -1;
    }
    if (queue.length) {
        drainQueue();
    }
}

function drainQueue() {
    if (draining) {
        return;
    }
    var timeout = runTimeout(cleanUpNextTick);
    draining = true;

    var len = queue.length;
    while(len) {
        currentQueue = queue;
        queue = [];
        while (++queueIndex < len) {
            if (currentQueue) {
                currentQueue[queueIndex].run();
            }
        }
        queueIndex = -1;
        len = queue.length;
    }
    currentQueue = null;
    draining = false;
    runClearTimeout(timeout);
}

process.nextTick = function (fun) {
    var args = new Array(arguments.length - 1);
    if (arguments.length > 1) {
        for (var i = 1; i < arguments.length; i++) {
            args[i - 1] = arguments[i];
        }
    }
    queue.push(new Item(fun, args));
    if (queue.length === 1 && !draining) {
        runTimeout(drainQueue);
    }
};

// v8 likes predictible objects
function Item(fun, array) {
    this.fun = fun;
    this.array = array;
}
Item.prototype.run = function () {
    this.fun.apply(null, this.array);
};
process.title = 'browser';
process.browser = true;
process.env = {};
process.argv = [];
process.version = ''; // empty string to avoid regexp issues
process.versions = {};

function noop() {}

process.on = noop;
process.addListener = noop;
process.once = noop;
process.off = noop;
process.removeListener = noop;
process.removeAllListeners = noop;
process.emit = noop;
process.prependListener = noop;
process.prependOnceListener = noop;

process.listeners = function (name) { return [] }

process.binding = function (name) {
    throw new Error('process.binding is not supported');
};

process.cwd = function () { return '/' };
process.chdir = function (dir) {
    throw new Error('process.chdir is not supported');
};
process.umask = function() { return 0; };

},{}],67:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

'use strict';

// If obj.hasOwnProperty has been overridden, then calling
// obj.hasOwnProperty(prop) will break.
// See: https://github.com/joyent/node/issues/1707
function hasOwnProperty(obj, prop) {
  return Object.prototype.hasOwnProperty.call(obj, prop);
}

module.exports = function(qs, sep, eq, options) {
  sep = sep || '&';
  eq = eq || '=';
  var obj = {};

  if (typeof qs !== 'string' || qs.length === 0) {
    return obj;
  }

  var regexp = /\+/g;
  qs = qs.split(sep);

  var maxKeys = 1000;
  if (options && typeof options.maxKeys === 'number') {
    maxKeys = options.maxKeys;
  }

  var len = qs.length;
  // maxKeys <= 0 means that we should not limit keys count
  if (maxKeys > 0 && len > maxKeys) {
    len = maxKeys;
  }

  for (var i = 0; i < len; ++i) {
    var x = qs[i].replace(regexp, '%20'),
        idx = x.indexOf(eq),
        kstr, vstr, k, v;

    if (idx >= 0) {
      kstr = x.substr(0, idx);
      vstr = x.substr(idx + 1);
    } else {
      kstr = x;
      vstr = '';
    }

    k = decodeURIComponent(kstr);
    v = decodeURIComponent(vstr);

    if (!hasOwnProperty(obj, k)) {
      obj[k] = v;
    } else if (isArray(obj[k])) {
      obj[k].push(v);
    } else {
      obj[k] = [obj[k], v];
    }
  }

  return obj;
};

var isArray = Array.isArray || function (xs) {
  return Object.prototype.toString.call(xs) === '[object Array]';
};

},{}],68:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

'use strict';

var stringifyPrimitive = function(v) {
  switch (typeof v) {
    case 'string':
      return v;

    case 'boolean':
      return v ? 'true' : 'false';

    case 'number':
      return isFinite(v) ? v : '';

    default:
      return '';
  }
};

module.exports = function(obj, sep, eq, name) {
  sep = sep || '&';
  eq = eq || '=';
  if (obj === null) {
    obj = undefined;
  }

  if (typeof obj === 'object') {
    return map(objectKeys(obj), function(k) {
      var ks = encodeURIComponent(stringifyPrimitive(k)) + eq;
      if (isArray(obj[k])) {
        return map(obj[k], function(v) {
          return ks + encodeURIComponent(stringifyPrimitive(v));
        }).join(sep);
      } else {
        return ks + encodeURIComponent(stringifyPrimitive(obj[k]));
      }
    }).join(sep);

  }

  if (!name) return '';
  return encodeURIComponent(stringifyPrimitive(name)) + eq +
         encodeURIComponent(stringifyPrimitive(obj));
};

var isArray = Array.isArray || function (xs) {
  return Object.prototype.toString.call(xs) === '[object Array]';
};

function map (xs, f) {
  if (xs.map) return xs.map(f);
  var res = [];
  for (var i = 0; i < xs.length; i++) {
    res.push(f(xs[i], i));
  }
  return res;
}

var objectKeys = Object.keys || function (obj) {
  var res = [];
  for (var key in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, key)) res.push(key);
  }
  return res;
};

},{}],69:[function(require,module,exports){
'use strict';

exports.decode = exports.parse = require('./decode');
exports.encode = exports.stringify = require('./encode');

},{"./decode":67,"./encode":68}],70:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// a duplex stream is just a stream that is both readable and writable.
// Since JS doesn't have multiple prototypal inheritance, this class
// prototypally inherits from Readable, and then parasitically from
// Writable.

'use strict';

/*<replacement>*/

var pna = require('process-nextick-args');
/*</replacement>*/

/*<replacement>*/
var objectKeys = Object.keys || function (obj) {
  var keys = [];
  for (var key in obj) {
    keys.push(key);
  }return keys;
};
/*</replacement>*/

module.exports = Duplex;

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

var Readable = require('./_stream_readable');
var Writable = require('./_stream_writable');

util.inherits(Duplex, Readable);

{
  // avoid scope creep, the keys array can then be collected
  var keys = objectKeys(Writable.prototype);
  for (var v = 0; v < keys.length; v++) {
    var method = keys[v];
    if (!Duplex.prototype[method]) Duplex.prototype[method] = Writable.prototype[method];
  }
}

function Duplex(options) {
  if (!(this instanceof Duplex)) return new Duplex(options);

  Readable.call(this, options);
  Writable.call(this, options);

  if (options && options.readable === false) this.readable = false;

  if (options && options.writable === false) this.writable = false;

  this.allowHalfOpen = true;
  if (options && options.allowHalfOpen === false) this.allowHalfOpen = false;

  this.once('end', onend);
}

Object.defineProperty(Duplex.prototype, 'writableHighWaterMark', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function () {
    return this._writableState.highWaterMark;
  }
});

// the no-half-open enforcer
function onend() {
  // if we allow half-open state, or if the writable side ended,
  // then we're ok.
  if (this.allowHalfOpen || this._writableState.ended) return;

  // no more data can be written.
  // But allow more writes to happen in this tick.
  pna.nextTick(onEndNT, this);
}

function onEndNT(self) {
  self.end();
}

Object.defineProperty(Duplex.prototype, 'destroyed', {
  get: function () {
    if (this._readableState === undefined || this._writableState === undefined) {
      return false;
    }
    return this._readableState.destroyed && this._writableState.destroyed;
  },
  set: function (value) {
    // we ignore the value if the stream
    // has not been initialized yet
    if (this._readableState === undefined || this._writableState === undefined) {
      return;
    }

    // backward compatibility, the user is explicitly
    // managing destroyed
    this._readableState.destroyed = value;
    this._writableState.destroyed = value;
  }
});

Duplex.prototype._destroy = function (err, cb) {
  this.push(null);
  this.end();

  pna.nextTick(cb, err);
};
},{"./_stream_readable":72,"./_stream_writable":74,"core-util-is":26,"inherits":31,"process-nextick-args":65}],71:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// a passthrough stream.
// basically just the most minimal sort of Transform stream.
// Every written chunk gets output as-is.

'use strict';

module.exports = PassThrough;

var Transform = require('./_stream_transform');

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

util.inherits(PassThrough, Transform);

function PassThrough(options) {
  if (!(this instanceof PassThrough)) return new PassThrough(options);

  Transform.call(this, options);
}

PassThrough.prototype._transform = function (chunk, encoding, cb) {
  cb(null, chunk);
};
},{"./_stream_transform":73,"core-util-is":26,"inherits":31}],72:[function(require,module,exports){
(function (process,global){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

'use strict';

/*<replacement>*/

var pna = require('process-nextick-args');
/*</replacement>*/

module.exports = Readable;

/*<replacement>*/
var isArray = require('isarray');
/*</replacement>*/

/*<replacement>*/
var Duplex;
/*</replacement>*/

Readable.ReadableState = ReadableState;

/*<replacement>*/
var EE = require('events').EventEmitter;

var EElistenerCount = function (emitter, type) {
  return emitter.listeners(type).length;
};
/*</replacement>*/

/*<replacement>*/
var Stream = require('./internal/streams/stream');
/*</replacement>*/

/*<replacement>*/

var Buffer = require('safe-buffer').Buffer;
var OurUint8Array = global.Uint8Array || function () {};
function _uint8ArrayToBuffer(chunk) {
  return Buffer.from(chunk);
}
function _isUint8Array(obj) {
  return Buffer.isBuffer(obj) || obj instanceof OurUint8Array;
}

/*</replacement>*/

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

/*<replacement>*/
var debugUtil = require('util');
var debug = void 0;
if (debugUtil && debugUtil.debuglog) {
  debug = debugUtil.debuglog('stream');
} else {
  debug = function () {};
}
/*</replacement>*/

var BufferList = require('./internal/streams/BufferList');
var destroyImpl = require('./internal/streams/destroy');
var StringDecoder;

util.inherits(Readable, Stream);

var kProxyEvents = ['error', 'close', 'destroy', 'pause', 'resume'];

function prependListener(emitter, event, fn) {
  // Sadly this is not cacheable as some libraries bundle their own
  // event emitter implementation with them.
  if (typeof emitter.prependListener === 'function') return emitter.prependListener(event, fn);

  // This is a hack to make sure that our error handler is attached before any
  // userland ones.  NEVER DO THIS. This is here only because this code needs
  // to continue to work with older versions of Node.js that do not include
  // the prependListener() method. The goal is to eventually remove this hack.
  if (!emitter._events || !emitter._events[event]) emitter.on(event, fn);else if (isArray(emitter._events[event])) emitter._events[event].unshift(fn);else emitter._events[event] = [fn, emitter._events[event]];
}

function ReadableState(options, stream) {
  Duplex = Duplex || require('./_stream_duplex');

  options = options || {};

  // Duplex streams are both readable and writable, but share
  // the same options object.
  // However, some cases require setting options to different
  // values for the readable and the writable sides of the duplex stream.
  // These options can be provided separately as readableXXX and writableXXX.
  var isDuplex = stream instanceof Duplex;

  // object stream flag. Used to make read(n) ignore n and to
  // make all the buffer merging and length checks go away
  this.objectMode = !!options.objectMode;

  if (isDuplex) this.objectMode = this.objectMode || !!options.readableObjectMode;

  // the point at which it stops calling _read() to fill the buffer
  // Note: 0 is a valid value, means "don't call _read preemptively ever"
  var hwm = options.highWaterMark;
  var readableHwm = options.readableHighWaterMark;
  var defaultHwm = this.objectMode ? 16 : 16 * 1024;

  if (hwm || hwm === 0) this.highWaterMark = hwm;else if (isDuplex && (readableHwm || readableHwm === 0)) this.highWaterMark = readableHwm;else this.highWaterMark = defaultHwm;

  // cast to ints.
  this.highWaterMark = Math.floor(this.highWaterMark);

  // A linked list is used to store data chunks instead of an array because the
  // linked list can remove elements from the beginning faster than
  // array.shift()
  this.buffer = new BufferList();
  this.length = 0;
  this.pipes = null;
  this.pipesCount = 0;
  this.flowing = null;
  this.ended = false;
  this.endEmitted = false;
  this.reading = false;

  // a flag to be able to tell if the event 'readable'/'data' is emitted
  // immediately, or on a later tick.  We set this to true at first, because
  // any actions that shouldn't happen until "later" should generally also
  // not happen before the first read call.
  this.sync = true;

  // whenever we return null, then we set a flag to say
  // that we're awaiting a 'readable' event emission.
  this.needReadable = false;
  this.emittedReadable = false;
  this.readableListening = false;
  this.resumeScheduled = false;

  // has it been destroyed
  this.destroyed = false;

  // Crypto is kind of old and crusty.  Historically, its default string
  // encoding is 'binary' so we have to make this configurable.
  // Everything else in the universe uses 'utf8', though.
  this.defaultEncoding = options.defaultEncoding || 'utf8';

  // the number of writers that are awaiting a drain event in .pipe()s
  this.awaitDrain = 0;

  // if true, a maybeReadMore has been scheduled
  this.readingMore = false;

  this.decoder = null;
  this.encoding = null;
  if (options.encoding) {
    if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder;
    this.decoder = new StringDecoder(options.encoding);
    this.encoding = options.encoding;
  }
}

function Readable(options) {
  Duplex = Duplex || require('./_stream_duplex');

  if (!(this instanceof Readable)) return new Readable(options);

  this._readableState = new ReadableState(options, this);

  // legacy
  this.readable = true;

  if (options) {
    if (typeof options.read === 'function') this._read = options.read;

    if (typeof options.destroy === 'function') this._destroy = options.destroy;
  }

  Stream.call(this);
}

Object.defineProperty(Readable.prototype, 'destroyed', {
  get: function () {
    if (this._readableState === undefined) {
      return false;
    }
    return this._readableState.destroyed;
  },
  set: function (value) {
    // we ignore the value if the stream
    // has not been initialized yet
    if (!this._readableState) {
      return;
    }

    // backward compatibility, the user is explicitly
    // managing destroyed
    this._readableState.destroyed = value;
  }
});

Readable.prototype.destroy = destroyImpl.destroy;
Readable.prototype._undestroy = destroyImpl.undestroy;
Readable.prototype._destroy = function (err, cb) {
  this.push(null);
  cb(err);
};

// Manually shove something into the read() buffer.
// This returns true if the highWaterMark has not been hit yet,
// similar to how Writable.write() returns true if you should
// write() some more.
Readable.prototype.push = function (chunk, encoding) {
  var state = this._readableState;
  var skipChunkCheck;

  if (!state.objectMode) {
    if (typeof chunk === 'string') {
      encoding = encoding || state.defaultEncoding;
      if (encoding !== state.encoding) {
        chunk = Buffer.from(chunk, encoding);
        encoding = '';
      }
      skipChunkCheck = true;
    }
  } else {
    skipChunkCheck = true;
  }

  return readableAddChunk(this, chunk, encoding, false, skipChunkCheck);
};

// Unshift should *always* be something directly out of read()
Readable.prototype.unshift = function (chunk) {
  return readableAddChunk(this, chunk, null, true, false);
};

function readableAddChunk(stream, chunk, encoding, addToFront, skipChunkCheck) {
  var state = stream._readableState;
  if (chunk === null) {
    state.reading = false;
    onEofChunk(stream, state);
  } else {
    var er;
    if (!skipChunkCheck) er = chunkInvalid(state, chunk);
    if (er) {
      stream.emit('error', er);
    } else if (state.objectMode || chunk && chunk.length > 0) {
      if (typeof chunk !== 'string' && !state.objectMode && Object.getPrototypeOf(chunk) !== Buffer.prototype) {
        chunk = _uint8ArrayToBuffer(chunk);
      }

      if (addToFront) {
        if (state.endEmitted) stream.emit('error', new Error('stream.unshift() after end event'));else addChunk(stream, state, chunk, true);
      } else if (state.ended) {
        stream.emit('error', new Error('stream.push() after EOF'));
      } else {
        state.reading = false;
        if (state.decoder && !encoding) {
          chunk = state.decoder.write(chunk);
          if (state.objectMode || chunk.length !== 0) addChunk(stream, state, chunk, false);else maybeReadMore(stream, state);
        } else {
          addChunk(stream, state, chunk, false);
        }
      }
    } else if (!addToFront) {
      state.reading = false;
    }
  }

  return needMoreData(state);
}

function addChunk(stream, state, chunk, addToFront) {
  if (state.flowing && state.length === 0 && !state.sync) {
    stream.emit('data', chunk);
    stream.read(0);
  } else {
    // update the buffer info.
    state.length += state.objectMode ? 1 : chunk.length;
    if (addToFront) state.buffer.unshift(chunk);else state.buffer.push(chunk);

    if (state.needReadable) emitReadable(stream);
  }
  maybeReadMore(stream, state);
}

function chunkInvalid(state, chunk) {
  var er;
  if (!_isUint8Array(chunk) && typeof chunk !== 'string' && chunk !== undefined && !state.objectMode) {
    er = new TypeError('Invalid non-string/buffer chunk');
  }
  return er;
}

// if it's past the high water mark, we can push in some more.
// Also, if we have no data yet, we can stand some
// more bytes.  This is to work around cases where hwm=0,
// such as the repl.  Also, if the push() triggered a
// readable event, and the user called read(largeNumber) such that
// needReadable was set, then we ought to push more, so that another
// 'readable' event will be triggered.
function needMoreData(state) {
  return !state.ended && (state.needReadable || state.length < state.highWaterMark || state.length === 0);
}

Readable.prototype.isPaused = function () {
  return this._readableState.flowing === false;
};

// backwards compatibility.
Readable.prototype.setEncoding = function (enc) {
  if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder;
  this._readableState.decoder = new StringDecoder(enc);
  this._readableState.encoding = enc;
  return this;
};

// Don't raise the hwm > 8MB
var MAX_HWM = 0x800000;
function computeNewHighWaterMark(n) {
  if (n >= MAX_HWM) {
    n = MAX_HWM;
  } else {
    // Get the next highest power of 2 to prevent increasing hwm excessively in
    // tiny amounts
    n--;
    n |= n >>> 1;
    n |= n >>> 2;
    n |= n >>> 4;
    n |= n >>> 8;
    n |= n >>> 16;
    n++;
  }
  return n;
}

// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function howMuchToRead(n, state) {
  if (n <= 0 || state.length === 0 && state.ended) return 0;
  if (state.objectMode) return 1;
  if (n !== n) {
    // Only flow one buffer at a time
    if (state.flowing && state.length) return state.buffer.head.data.length;else return state.length;
  }
  // If we're asking for more than the current hwm, then raise the hwm.
  if (n > state.highWaterMark) state.highWaterMark = computeNewHighWaterMark(n);
  if (n <= state.length) return n;
  // Don't have enough
  if (!state.ended) {
    state.needReadable = true;
    return 0;
  }
  return state.length;
}

// you can override either this method, or the async _read(n) below.
Readable.prototype.read = function (n) {
  debug('read', n);
  n = parseInt(n, 10);
  var state = this._readableState;
  var nOrig = n;

  if (n !== 0) state.emittedReadable = false;

  // if we're doing read(0) to trigger a readable event, but we
  // already have a bunch of data in the buffer, then just trigger
  // the 'readable' event and move on.
  if (n === 0 && state.needReadable && (state.length >= state.highWaterMark || state.ended)) {
    debug('read: emitReadable', state.length, state.ended);
    if (state.length === 0 && state.ended) endReadable(this);else emitReadable(this);
    return null;
  }

  n = howMuchToRead(n, state);

  // if we've ended, and we're now clear, then finish it up.
  if (n === 0 && state.ended) {
    if (state.length === 0) endReadable(this);
    return null;
  }

  // All the actual chunk generation logic needs to be
  // *below* the call to _read.  The reason is that in certain
  // synthetic stream cases, such as passthrough streams, _read
  // may be a completely synchronous operation which may change
  // the state of the read buffer, providing enough data when
  // before there was *not* enough.
  //
  // So, the steps are:
  // 1. Figure out what the state of things will be after we do
  // a read from the buffer.
  //
  // 2. If that resulting state will trigger a _read, then call _read.
  // Note that this may be asynchronous, or synchronous.  Yes, it is
  // deeply ugly to write APIs this way, but that still doesn't mean
  // that the Readable class should behave improperly, as streams are
  // designed to be sync/async agnostic.
  // Take note if the _read call is sync or async (ie, if the read call
  // has returned yet), so that we know whether or not it's safe to emit
  // 'readable' etc.
  //
  // 3. Actually pull the requested chunks out of the buffer and return.

  // if we need a readable event, then we need to do some reading.
  var doRead = state.needReadable;
  debug('need readable', doRead);

  // if we currently have less than the highWaterMark, then also read some
  if (state.length === 0 || state.length - n < state.highWaterMark) {
    doRead = true;
    debug('length less than watermark', doRead);
  }

  // however, if we've ended, then there's no point, and if we're already
  // reading, then it's unnecessary.
  if (state.ended || state.reading) {
    doRead = false;
    debug('reading or ended', doRead);
  } else if (doRead) {
    debug('do read');
    state.reading = true;
    state.sync = true;
    // if the length is currently zero, then we *need* a readable event.
    if (state.length === 0) state.needReadable = true;
    // call internal read method
    this._read(state.highWaterMark);
    state.sync = false;
    // If _read pushed data synchronously, then `reading` will be false,
    // and we need to re-evaluate how much data we can return to the user.
    if (!state.reading) n = howMuchToRead(nOrig, state);
  }

  var ret;
  if (n > 0) ret = fromList(n, state);else ret = null;

  if (ret === null) {
    state.needReadable = true;
    n = 0;
  } else {
    state.length -= n;
  }

  if (state.length === 0) {
    // If we have nothing in the buffer, then we want to know
    // as soon as we *do* get something into the buffer.
    if (!state.ended) state.needReadable = true;

    // If we tried to read() past the EOF, then emit end on the next tick.
    if (nOrig !== n && state.ended) endReadable(this);
  }

  if (ret !== null) this.emit('data', ret);

  return ret;
};

function onEofChunk(stream, state) {
  if (state.ended) return;
  if (state.decoder) {
    var chunk = state.decoder.end();
    if (chunk && chunk.length) {
      state.buffer.push(chunk);
      state.length += state.objectMode ? 1 : chunk.length;
    }
  }
  state.ended = true;

  // emit 'readable' now to make sure it gets picked up.
  emitReadable(stream);
}

// Don't emit readable right away in sync mode, because this can trigger
// another read() call => stack overflow.  This way, it might trigger
// a nextTick recursion warning, but that's not so bad.
function emitReadable(stream) {
  var state = stream._readableState;
  state.needReadable = false;
  if (!state.emittedReadable) {
    debug('emitReadable', state.flowing);
    state.emittedReadable = true;
    if (state.sync) pna.nextTick(emitReadable_, stream);else emitReadable_(stream);
  }
}

function emitReadable_(stream) {
  debug('emit readable');
  stream.emit('readable');
  flow(stream);
}

// at this point, the user has presumably seen the 'readable' event,
// and called read() to consume some data.  that may have triggered
// in turn another _read(n) call, in which case reading = true if
// it's in progress.
// However, if we're not ended, or reading, and the length < hwm,
// then go ahead and try to read some more preemptively.
function maybeReadMore(stream, state) {
  if (!state.readingMore) {
    state.readingMore = true;
    pna.nextTick(maybeReadMore_, stream, state);
  }
}

function maybeReadMore_(stream, state) {
  var len = state.length;
  while (!state.reading && !state.flowing && !state.ended && state.length < state.highWaterMark) {
    debug('maybeReadMore read 0');
    stream.read(0);
    if (len === state.length)
      // didn't get any data, stop spinning.
      break;else len = state.length;
  }
  state.readingMore = false;
}

// abstract method.  to be overridden in specific implementation classes.
// call cb(er, data) where data is <= n in length.
// for virtual (non-string, non-buffer) streams, "length" is somewhat
// arbitrary, and perhaps not very meaningful.
Readable.prototype._read = function (n) {
  this.emit('error', new Error('_read() is not implemented'));
};

Readable.prototype.pipe = function (dest, pipeOpts) {
  var src = this;
  var state = this._readableState;

  switch (state.pipesCount) {
    case 0:
      state.pipes = dest;
      break;
    case 1:
      state.pipes = [state.pipes, dest];
      break;
    default:
      state.pipes.push(dest);
      break;
  }
  state.pipesCount += 1;
  debug('pipe count=%d opts=%j', state.pipesCount, pipeOpts);

  var doEnd = (!pipeOpts || pipeOpts.end !== false) && dest !== process.stdout && dest !== process.stderr;

  var endFn = doEnd ? onend : unpipe;
  if (state.endEmitted) pna.nextTick(endFn);else src.once('end', endFn);

  dest.on('unpipe', onunpipe);
  function onunpipe(readable, unpipeInfo) {
    debug('onunpipe');
    if (readable === src) {
      if (unpipeInfo && unpipeInfo.hasUnpiped === false) {
        unpipeInfo.hasUnpiped = true;
        cleanup();
      }
    }
  }

  function onend() {
    debug('onend');
    dest.end();
  }

  // when the dest drains, it reduces the awaitDrain counter
  // on the source.  This would be more elegant with a .once()
  // handler in flow(), but adding and removing repeatedly is
  // too slow.
  var ondrain = pipeOnDrain(src);
  dest.on('drain', ondrain);

  var cleanedUp = false;
  function cleanup() {
    debug('cleanup');
    // cleanup event handlers once the pipe is broken
    dest.removeListener('close', onclose);
    dest.removeListener('finish', onfinish);
    dest.removeListener('drain', ondrain);
    dest.removeListener('error', onerror);
    dest.removeListener('unpipe', onunpipe);
    src.removeListener('end', onend);
    src.removeListener('end', unpipe);
    src.removeListener('data', ondata);

    cleanedUp = true;

    // if the reader is waiting for a drain event from this
    // specific writer, then it would cause it to never start
    // flowing again.
    // So, if this is awaiting a drain, then we just call it now.
    // If we don't know, then assume that we are waiting for one.
    if (state.awaitDrain && (!dest._writableState || dest._writableState.needDrain)) ondrain();
  }

  // If the user pushes more data while we're writing to dest then we'll end up
  // in ondata again. However, we only want to increase awaitDrain once because
  // dest will only emit one 'drain' event for the multiple writes.
  // => Introduce a guard on increasing awaitDrain.
  var increasedAwaitDrain = false;
  src.on('data', ondata);
  function ondata(chunk) {
    debug('ondata');
    increasedAwaitDrain = false;
    var ret = dest.write(chunk);
    if (false === ret && !increasedAwaitDrain) {
      // If the user unpiped during `dest.write()`, it is possible
      // to get stuck in a permanently paused state if that write
      // also returned false.
      // => Check whether `dest` is still a piping destination.
      if ((state.pipesCount === 1 && state.pipes === dest || state.pipesCount > 1 && indexOf(state.pipes, dest) !== -1) && !cleanedUp) {
        debug('false write response, pause', src._readableState.awaitDrain);
        src._readableState.awaitDrain++;
        increasedAwaitDrain = true;
      }
      src.pause();
    }
  }

  // if the dest has an error, then stop piping into it.
  // however, don't suppress the throwing behavior for this.
  function onerror(er) {
    debug('onerror', er);
    unpipe();
    dest.removeListener('error', onerror);
    if (EElistenerCount(dest, 'error') === 0) dest.emit('error', er);
  }

  // Make sure our error handler is attached before userland ones.
  prependListener(dest, 'error', onerror);

  // Both close and finish should trigger unpipe, but only once.
  function onclose() {
    dest.removeListener('finish', onfinish);
    unpipe();
  }
  dest.once('close', onclose);
  function onfinish() {
    debug('onfinish');
    dest.removeListener('close', onclose);
    unpipe();
  }
  dest.once('finish', onfinish);

  function unpipe() {
    debug('unpipe');
    src.unpipe(dest);
  }

  // tell the dest that it's being piped to
  dest.emit('pipe', src);

  // start the flow if it hasn't been started already.
  if (!state.flowing) {
    debug('pipe resume');
    src.resume();
  }

  return dest;
};

function pipeOnDrain(src) {
  return function () {
    var state = src._readableState;
    debug('pipeOnDrain', state.awaitDrain);
    if (state.awaitDrain) state.awaitDrain--;
    if (state.awaitDrain === 0 && EElistenerCount(src, 'data')) {
      state.flowing = true;
      flow(src);
    }
  };
}

Readable.prototype.unpipe = function (dest) {
  var state = this._readableState;
  var unpipeInfo = { hasUnpiped: false };

  // if we're not piping anywhere, then do nothing.
  if (state.pipesCount === 0) return this;

  // just one destination.  most common case.
  if (state.pipesCount === 1) {
    // passed in one, but it's not the right one.
    if (dest && dest !== state.pipes) return this;

    if (!dest) dest = state.pipes;

    // got a match.
    state.pipes = null;
    state.pipesCount = 0;
    state.flowing = false;
    if (dest) dest.emit('unpipe', this, unpipeInfo);
    return this;
  }

  // slow case. multiple pipe destinations.

  if (!dest) {
    // remove all.
    var dests = state.pipes;
    var len = state.pipesCount;
    state.pipes = null;
    state.pipesCount = 0;
    state.flowing = false;

    for (var i = 0; i < len; i++) {
      dests[i].emit('unpipe', this, unpipeInfo);
    }return this;
  }

  // try to find the right one.
  var index = indexOf(state.pipes, dest);
  if (index === -1) return this;

  state.pipes.splice(index, 1);
  state.pipesCount -= 1;
  if (state.pipesCount === 1) state.pipes = state.pipes[0];

  dest.emit('unpipe', this, unpipeInfo);

  return this;
};

// set up data events if they are asked for
// Ensure readable listeners eventually get something
Readable.prototype.on = function (ev, fn) {
  var res = Stream.prototype.on.call(this, ev, fn);

  if (ev === 'data') {
    // Start flowing on next tick if stream isn't explicitly paused
    if (this._readableState.flowing !== false) this.resume();
  } else if (ev === 'readable') {
    var state = this._readableState;
    if (!state.endEmitted && !state.readableListening) {
      state.readableListening = state.needReadable = true;
      state.emittedReadable = false;
      if (!state.reading) {
        pna.nextTick(nReadingNextTick, this);
      } else if (state.length) {
        emitReadable(this);
      }
    }
  }

  return res;
};
Readable.prototype.addListener = Readable.prototype.on;

function nReadingNextTick(self) {
  debug('readable nexttick read 0');
  self.read(0);
}

// pause() and resume() are remnants of the legacy readable stream API
// If the user uses them, then switch into old mode.
Readable.prototype.resume = function () {
  var state = this._readableState;
  if (!state.flowing) {
    debug('resume');
    state.flowing = true;
    resume(this, state);
  }
  return this;
};

function resume(stream, state) {
  if (!state.resumeScheduled) {
    state.resumeScheduled = true;
    pna.nextTick(resume_, stream, state);
  }
}

function resume_(stream, state) {
  if (!state.reading) {
    debug('resume read 0');
    stream.read(0);
  }

  state.resumeScheduled = false;
  state.awaitDrain = 0;
  stream.emit('resume');
  flow(stream);
  if (state.flowing && !state.reading) stream.read(0);
}

Readable.prototype.pause = function () {
  debug('call pause flowing=%j', this._readableState.flowing);
  if (false !== this._readableState.flowing) {
    debug('pause');
    this._readableState.flowing = false;
    this.emit('pause');
  }
  return this;
};

function flow(stream) {
  var state = stream._readableState;
  debug('flow', state.flowing);
  while (state.flowing && stream.read() !== null) {}
}

// wrap an old-style stream as the async data source.
// This is *not* part of the readable stream interface.
// It is an ugly unfortunate mess of history.
Readable.prototype.wrap = function (stream) {
  var _this = this;

  var state = this._readableState;
  var paused = false;

  stream.on('end', function () {
    debug('wrapped end');
    if (state.decoder && !state.ended) {
      var chunk = state.decoder.end();
      if (chunk && chunk.length) _this.push(chunk);
    }

    _this.push(null);
  });

  stream.on('data', function (chunk) {
    debug('wrapped data');
    if (state.decoder) chunk = state.decoder.write(chunk);

    // don't skip over falsy values in objectMode
    if (state.objectMode && (chunk === null || chunk === undefined)) return;else if (!state.objectMode && (!chunk || !chunk.length)) return;

    var ret = _this.push(chunk);
    if (!ret) {
      paused = true;
      stream.pause();
    }
  });

  // proxy all the other methods.
  // important when wrapping filters and duplexes.
  for (var i in stream) {
    if (this[i] === undefined && typeof stream[i] === 'function') {
      this[i] = function (method) {
        return function () {
          return stream[method].apply(stream, arguments);
        };
      }(i);
    }
  }

  // proxy certain important events.
  for (var n = 0; n < kProxyEvents.length; n++) {
    stream.on(kProxyEvents[n], this.emit.bind(this, kProxyEvents[n]));
  }

  // when we try to consume some more bytes, simply unpause the
  // underlying stream.
  this._read = function (n) {
    debug('wrapped _read', n);
    if (paused) {
      paused = false;
      stream.resume();
    }
  };

  return this;
};

Object.defineProperty(Readable.prototype, 'readableHighWaterMark', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function () {
    return this._readableState.highWaterMark;
  }
});

// exposed for testing purposes only.
Readable._fromList = fromList;

// Pluck off n bytes from an array of buffers.
// Length is the combined lengths of all the buffers in the list.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function fromList(n, state) {
  // nothing buffered
  if (state.length === 0) return null;

  var ret;
  if (state.objectMode) ret = state.buffer.shift();else if (!n || n >= state.length) {
    // read it all, truncate the list
    if (state.decoder) ret = state.buffer.join('');else if (state.buffer.length === 1) ret = state.buffer.head.data;else ret = state.buffer.concat(state.length);
    state.buffer.clear();
  } else {
    // read part of list
    ret = fromListPartial(n, state.buffer, state.decoder);
  }

  return ret;
}

// Extracts only enough buffered data to satisfy the amount requested.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function fromListPartial(n, list, hasStrings) {
  var ret;
  if (n < list.head.data.length) {
    // slice is the same for buffers and strings
    ret = list.head.data.slice(0, n);
    list.head.data = list.head.data.slice(n);
  } else if (n === list.head.data.length) {
    // first chunk is a perfect match
    ret = list.shift();
  } else {
    // result spans more than one buffer
    ret = hasStrings ? copyFromBufferString(n, list) : copyFromBuffer(n, list);
  }
  return ret;
}

// Copies a specified amount of characters from the list of buffered data
// chunks.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function copyFromBufferString(n, list) {
  var p = list.head;
  var c = 1;
  var ret = p.data;
  n -= ret.length;
  while (p = p.next) {
    var str = p.data;
    var nb = n > str.length ? str.length : n;
    if (nb === str.length) ret += str;else ret += str.slice(0, n);
    n -= nb;
    if (n === 0) {
      if (nb === str.length) {
        ++c;
        if (p.next) list.head = p.next;else list.head = list.tail = null;
      } else {
        list.head = p;
        p.data = str.slice(nb);
      }
      break;
    }
    ++c;
  }
  list.length -= c;
  return ret;
}

// Copies a specified amount of bytes from the list of buffered data chunks.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function copyFromBuffer(n, list) {
  var ret = Buffer.allocUnsafe(n);
  var p = list.head;
  var c = 1;
  p.data.copy(ret);
  n -= p.data.length;
  while (p = p.next) {
    var buf = p.data;
    var nb = n > buf.length ? buf.length : n;
    buf.copy(ret, ret.length - n, 0, nb);
    n -= nb;
    if (n === 0) {
      if (nb === buf.length) {
        ++c;
        if (p.next) list.head = p.next;else list.head = list.tail = null;
      } else {
        list.head = p;
        p.data = buf.slice(nb);
      }
      break;
    }
    ++c;
  }
  list.length -= c;
  return ret;
}

function endReadable(stream) {
  var state = stream._readableState;

  // If we get here before consuming all the bytes, then that is a
  // bug in node.  Should never happen.
  if (state.length > 0) throw new Error('"endReadable()" called on non-empty stream');

  if (!state.endEmitted) {
    state.ended = true;
    pna.nextTick(endReadableNT, state, stream);
  }
}

function endReadableNT(state, stream) {
  // Check that we didn't get one last unshift.
  if (!state.endEmitted && state.length === 0) {
    state.endEmitted = true;
    stream.readable = false;
    stream.emit('end');
  }
}

function indexOf(xs, x) {
  for (var i = 0, l = xs.length; i < l; i++) {
    if (xs[i] === x) return i;
  }
  return -1;
}
}).call(this,require('_process'),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{"./_stream_duplex":70,"./internal/streams/BufferList":75,"./internal/streams/destroy":76,"./internal/streams/stream":77,"_process":66,"core-util-is":26,"events":27,"inherits":31,"isarray":33,"process-nextick-args":65,"safe-buffer":79,"string_decoder/":84,"util":21}],73:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// a transform stream is a readable/writable stream where you do
// something with the data.  Sometimes it's called a "filter",
// but that's not a great name for it, since that implies a thing where
// some bits pass through, and others are simply ignored.  (That would
// be a valid example of a transform, of course.)
//
// While the output is causally related to the input, it's not a
// necessarily symmetric or synchronous transformation.  For example,
// a zlib stream might take multiple plain-text writes(), and then
// emit a single compressed chunk some time in the future.
//
// Here's how this works:
//
// The Transform stream has all the aspects of the readable and writable
// stream classes.  When you write(chunk), that calls _write(chunk,cb)
// internally, and returns false if there's a lot of pending writes
// buffered up.  When you call read(), that calls _read(n) until
// there's enough pending readable data buffered up.
//
// In a transform stream, the written data is placed in a buffer.  When
// _read(n) is called, it transforms the queued up data, calling the
// buffered _write cb's as it consumes chunks.  If consuming a single
// written chunk would result in multiple output chunks, then the first
// outputted bit calls the readcb, and subsequent chunks just go into
// the read buffer, and will cause it to emit 'readable' if necessary.
//
// This way, back-pressure is actually determined by the reading side,
// since _read has to be called to start processing a new chunk.  However,
// a pathological inflate type of transform can cause excessive buffering
// here.  For example, imagine a stream where every byte of input is
// interpreted as an integer from 0-255, and then results in that many
// bytes of output.  Writing the 4 bytes {ff,ff,ff,ff} would result in
// 1kb of data being output.  In this case, you could write a very small
// amount of input, and end up with a very large amount of output.  In
// such a pathological inflating mechanism, there'd be no way to tell
// the system to stop doing the transform.  A single 4MB write could
// cause the system to run out of memory.
//
// However, even in such a pathological case, only a single written chunk
// would be consumed, and then the rest would wait (un-transformed) until
// the results of the previous transformed chunk were consumed.

'use strict';

module.exports = Transform;

var Duplex = require('./_stream_duplex');

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

util.inherits(Transform, Duplex);

function afterTransform(er, data) {
  var ts = this._transformState;
  ts.transforming = false;

  var cb = ts.writecb;

  if (!cb) {
    return this.emit('error', new Error('write callback called multiple times'));
  }

  ts.writechunk = null;
  ts.writecb = null;

  if (data != null) // single equals check for both `null` and `undefined`
    this.push(data);

  cb(er);

  var rs = this._readableState;
  rs.reading = false;
  if (rs.needReadable || rs.length < rs.highWaterMark) {
    this._read(rs.highWaterMark);
  }
}

function Transform(options) {
  if (!(this instanceof Transform)) return new Transform(options);

  Duplex.call(this, options);

  this._transformState = {
    afterTransform: afterTransform.bind(this),
    needTransform: false,
    transforming: false,
    writecb: null,
    writechunk: null,
    writeencoding: null
  };

  // start out asking for a readable event once data is transformed.
  this._readableState.needReadable = true;

  // we have implemented the _read method, and done the other things
  // that Readable wants before the first _read call, so unset the
  // sync guard flag.
  this._readableState.sync = false;

  if (options) {
    if (typeof options.transform === 'function') this._transform = options.transform;

    if (typeof options.flush === 'function') this._flush = options.flush;
  }

  // When the writable side finishes, then flush out anything remaining.
  this.on('prefinish', prefinish);
}

function prefinish() {
  var _this = this;

  if (typeof this._flush === 'function') {
    this._flush(function (er, data) {
      done(_this, er, data);
    });
  } else {
    done(this, null, null);
  }
}

Transform.prototype.push = function (chunk, encoding) {
  this._transformState.needTransform = false;
  return Duplex.prototype.push.call(this, chunk, encoding);
};

// This is the part where you do stuff!
// override this function in implementation classes.
// 'chunk' is an input chunk.
//
// Call `push(newChunk)` to pass along transformed output
// to the readable side.  You may call 'push' zero or more times.
//
// Call `cb(err)` when you are done with this chunk.  If you pass
// an error, then that'll put the hurt on the whole operation.  If you
// never call cb(), then you'll never get another chunk.
Transform.prototype._transform = function (chunk, encoding, cb) {
  throw new Error('_transform() is not implemented');
};

Transform.prototype._write = function (chunk, encoding, cb) {
  var ts = this._transformState;
  ts.writecb = cb;
  ts.writechunk = chunk;
  ts.writeencoding = encoding;
  if (!ts.transforming) {
    var rs = this._readableState;
    if (ts.needTransform || rs.needReadable || rs.length < rs.highWaterMark) this._read(rs.highWaterMark);
  }
};

// Doesn't matter what the args are here.
// _transform does all the work.
// That we got here means that the readable side wants more data.
Transform.prototype._read = function (n) {
  var ts = this._transformState;

  if (ts.writechunk !== null && ts.writecb && !ts.transforming) {
    ts.transforming = true;
    this._transform(ts.writechunk, ts.writeencoding, ts.afterTransform);
  } else {
    // mark that we need a transform, so that any data that comes in
    // will get processed, now that we've asked for it.
    ts.needTransform = true;
  }
};

Transform.prototype._destroy = function (err, cb) {
  var _this2 = this;

  Duplex.prototype._destroy.call(this, err, function (err2) {
    cb(err2);
    _this2.emit('close');
  });
};

function done(stream, er, data) {
  if (er) return stream.emit('error', er);

  if (data != null) // single equals check for both `null` and `undefined`
    stream.push(data);

  // if there's nothing in the write buffer, then that means
  // that nothing more will ever be provided
  if (stream._writableState.length) throw new Error('Calling transform done when ws.length != 0');

  if (stream._transformState.transforming) throw new Error('Calling transform done when still transforming');

  return stream.push(null);
}
},{"./_stream_duplex":70,"core-util-is":26,"inherits":31}],74:[function(require,module,exports){
(function (process,global,setImmediate){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// A bit simpler than readable streams.
// Implement an async ._write(chunk, encoding, cb), and it'll handle all
// the drain event emission and buffering.

'use strict';

/*<replacement>*/

var pna = require('process-nextick-args');
/*</replacement>*/

module.exports = Writable;

/* <replacement> */
function WriteReq(chunk, encoding, cb) {
  this.chunk = chunk;
  this.encoding = encoding;
  this.callback = cb;
  this.next = null;
}

// It seems a linked list but it is not
// there will be only 2 of these for each stream
function CorkedRequest(state) {
  var _this = this;

  this.next = null;
  this.entry = null;
  this.finish = function () {
    onCorkedFinish(_this, state);
  };
}
/* </replacement> */

/*<replacement>*/
var asyncWrite = !process.browser && ['v0.10', 'v0.9.'].indexOf(process.version.slice(0, 5)) > -1 ? setImmediate : pna.nextTick;
/*</replacement>*/

/*<replacement>*/
var Duplex;
/*</replacement>*/

Writable.WritableState = WritableState;

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

/*<replacement>*/
var internalUtil = {
  deprecate: require('util-deprecate')
};
/*</replacement>*/

/*<replacement>*/
var Stream = require('./internal/streams/stream');
/*</replacement>*/

/*<replacement>*/

var Buffer = require('safe-buffer').Buffer;
var OurUint8Array = global.Uint8Array || function () {};
function _uint8ArrayToBuffer(chunk) {
  return Buffer.from(chunk);
}
function _isUint8Array(obj) {
  return Buffer.isBuffer(obj) || obj instanceof OurUint8Array;
}

/*</replacement>*/

var destroyImpl = require('./internal/streams/destroy');

util.inherits(Writable, Stream);

function nop() {}

function WritableState(options, stream) {
  Duplex = Duplex || require('./_stream_duplex');

  options = options || {};

  // Duplex streams are both readable and writable, but share
  // the same options object.
  // However, some cases require setting options to different
  // values for the readable and the writable sides of the duplex stream.
  // These options can be provided separately as readableXXX and writableXXX.
  var isDuplex = stream instanceof Duplex;

  // object stream flag to indicate whether or not this stream
  // contains buffers or objects.
  this.objectMode = !!options.objectMode;

  if (isDuplex) this.objectMode = this.objectMode || !!options.writableObjectMode;

  // the point at which write() starts returning false
  // Note: 0 is a valid value, means that we always return false if
  // the entire buffer is not flushed immediately on write()
  var hwm = options.highWaterMark;
  var writableHwm = options.writableHighWaterMark;
  var defaultHwm = this.objectMode ? 16 : 16 * 1024;

  if (hwm || hwm === 0) this.highWaterMark = hwm;else if (isDuplex && (writableHwm || writableHwm === 0)) this.highWaterMark = writableHwm;else this.highWaterMark = defaultHwm;

  // cast to ints.
  this.highWaterMark = Math.floor(this.highWaterMark);

  // if _final has been called
  this.finalCalled = false;

  // drain event flag.
  this.needDrain = false;
  // at the start of calling end()
  this.ending = false;
  // when end() has been called, and returned
  this.ended = false;
  // when 'finish' is emitted
  this.finished = false;

  // has it been destroyed
  this.destroyed = false;

  // should we decode strings into buffers before passing to _write?
  // this is here so that some node-core streams can optimize string
  // handling at a lower level.
  var noDecode = options.decodeStrings === false;
  this.decodeStrings = !noDecode;

  // Crypto is kind of old and crusty.  Historically, its default string
  // encoding is 'binary' so we have to make this configurable.
  // Everything else in the universe uses 'utf8', though.
  this.defaultEncoding = options.defaultEncoding || 'utf8';

  // not an actual buffer we keep track of, but a measurement
  // of how much we're waiting to get pushed to some underlying
  // socket or file.
  this.length = 0;

  // a flag to see when we're in the middle of a write.
  this.writing = false;

  // when true all writes will be buffered until .uncork() call
  this.corked = 0;

  // a flag to be able to tell if the onwrite cb is called immediately,
  // or on a later tick.  We set this to true at first, because any
  // actions that shouldn't happen until "later" should generally also
  // not happen before the first write call.
  this.sync = true;

  // a flag to know if we're processing previously buffered items, which
  // may call the _write() callback in the same tick, so that we don't
  // end up in an overlapped onwrite situation.
  this.bufferProcessing = false;

  // the callback that's passed to _write(chunk,cb)
  this.onwrite = function (er) {
    onwrite(stream, er);
  };

  // the callback that the user supplies to write(chunk,encoding,cb)
  this.writecb = null;

  // the amount that is being written when _write is called.
  this.writelen = 0;

  this.bufferedRequest = null;
  this.lastBufferedRequest = null;

  // number of pending user-supplied write callbacks
  // this must be 0 before 'finish' can be emitted
  this.pendingcb = 0;

  // emit prefinish if the only thing we're waiting for is _write cbs
  // This is relevant for synchronous Transform streams
  this.prefinished = false;

  // True if the error was already emitted and should not be thrown again
  this.errorEmitted = false;

  // count buffered requests
  this.bufferedRequestCount = 0;

  // allocate the first CorkedRequest, there is always
  // one allocated and free to use, and we maintain at most two
  this.corkedRequestsFree = new CorkedRequest(this);
}

WritableState.prototype.getBuffer = function getBuffer() {
  var current = this.bufferedRequest;
  var out = [];
  while (current) {
    out.push(current);
    current = current.next;
  }
  return out;
};

(function () {
  try {
    Object.defineProperty(WritableState.prototype, 'buffer', {
      get: internalUtil.deprecate(function () {
        return this.getBuffer();
      }, '_writableState.buffer is deprecated. Use _writableState.getBuffer ' + 'instead.', 'DEP0003')
    });
  } catch (_) {}
})();

// Test _writableState for inheritance to account for Duplex streams,
// whose prototype chain only points to Readable.
var realHasInstance;
if (typeof Symbol === 'function' && Symbol.hasInstance && typeof Function.prototype[Symbol.hasInstance] === 'function') {
  realHasInstance = Function.prototype[Symbol.hasInstance];
  Object.defineProperty(Writable, Symbol.hasInstance, {
    value: function (object) {
      if (realHasInstance.call(this, object)) return true;
      if (this !== Writable) return false;

      return object && object._writableState instanceof WritableState;
    }
  });
} else {
  realHasInstance = function (object) {
    return object instanceof this;
  };
}

function Writable(options) {
  Duplex = Duplex || require('./_stream_duplex');

  // Writable ctor is applied to Duplexes, too.
  // `realHasInstance` is necessary because using plain `instanceof`
  // would return false, as no `_writableState` property is attached.

  // Trying to use the custom `instanceof` for Writable here will also break the
  // Node.js LazyTransform implementation, which has a non-trivial getter for
  // `_writableState` that would lead to infinite recursion.
  if (!realHasInstance.call(Writable, this) && !(this instanceof Duplex)) {
    return new Writable(options);
  }

  this._writableState = new WritableState(options, this);

  // legacy.
  this.writable = true;

  if (options) {
    if (typeof options.write === 'function') this._write = options.write;

    if (typeof options.writev === 'function') this._writev = options.writev;

    if (typeof options.destroy === 'function') this._destroy = options.destroy;

    if (typeof options.final === 'function') this._final = options.final;
  }

  Stream.call(this);
}

// Otherwise people can pipe Writable streams, which is just wrong.
Writable.prototype.pipe = function () {
  this.emit('error', new Error('Cannot pipe, not readable'));
};

function writeAfterEnd(stream, cb) {
  var er = new Error('write after end');
  // TODO: defer error events consistently everywhere, not just the cb
  stream.emit('error', er);
  pna.nextTick(cb, er);
}

// Checks that a user-supplied chunk is valid, especially for the particular
// mode the stream is in. Currently this means that `null` is never accepted
// and undefined/non-string values are only allowed in object mode.
function validChunk(stream, state, chunk, cb) {
  var valid = true;
  var er = false;

  if (chunk === null) {
    er = new TypeError('May not write null values to stream');
  } else if (typeof chunk !== 'string' && chunk !== undefined && !state.objectMode) {
    er = new TypeError('Invalid non-string/buffer chunk');
  }
  if (er) {
    stream.emit('error', er);
    pna.nextTick(cb, er);
    valid = false;
  }
  return valid;
}

Writable.prototype.write = function (chunk, encoding, cb) {
  var state = this._writableState;
  var ret = false;
  var isBuf = !state.objectMode && _isUint8Array(chunk);

  if (isBuf && !Buffer.isBuffer(chunk)) {
    chunk = _uint8ArrayToBuffer(chunk);
  }

  if (typeof encoding === 'function') {
    cb = encoding;
    encoding = null;
  }

  if (isBuf) encoding = 'buffer';else if (!encoding) encoding = state.defaultEncoding;

  if (typeof cb !== 'function') cb = nop;

  if (state.ended) writeAfterEnd(this, cb);else if (isBuf || validChunk(this, state, chunk, cb)) {
    state.pendingcb++;
    ret = writeOrBuffer(this, state, isBuf, chunk, encoding, cb);
  }

  return ret;
};

Writable.prototype.cork = function () {
  var state = this._writableState;

  state.corked++;
};

Writable.prototype.uncork = function () {
  var state = this._writableState;

  if (state.corked) {
    state.corked--;

    if (!state.writing && !state.corked && !state.finished && !state.bufferProcessing && state.bufferedRequest) clearBuffer(this, state);
  }
};

Writable.prototype.setDefaultEncoding = function setDefaultEncoding(encoding) {
  // node::ParseEncoding() requires lower case.
  if (typeof encoding === 'string') encoding = encoding.toLowerCase();
  if (!(['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', 'raw'].indexOf((encoding + '').toLowerCase()) > -1)) throw new TypeError('Unknown encoding: ' + encoding);
  this._writableState.defaultEncoding = encoding;
  return this;
};

function decodeChunk(state, chunk, encoding) {
  if (!state.objectMode && state.decodeStrings !== false && typeof chunk === 'string') {
    chunk = Buffer.from(chunk, encoding);
  }
  return chunk;
}

Object.defineProperty(Writable.prototype, 'writableHighWaterMark', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function () {
    return this._writableState.highWaterMark;
  }
});

// if we're already writing something, then just put this
// in the queue, and wait our turn.  Otherwise, call _write
// If we return false, then we need a drain event, so set that flag.
function writeOrBuffer(stream, state, isBuf, chunk, encoding, cb) {
  if (!isBuf) {
    var newChunk = decodeChunk(state, chunk, encoding);
    if (chunk !== newChunk) {
      isBuf = true;
      encoding = 'buffer';
      chunk = newChunk;
    }
  }
  var len = state.objectMode ? 1 : chunk.length;

  state.length += len;

  var ret = state.length < state.highWaterMark;
  // we must ensure that previous needDrain will not be reset to false.
  if (!ret) state.needDrain = true;

  if (state.writing || state.corked) {
    var last = state.lastBufferedRequest;
    state.lastBufferedRequest = {
      chunk: chunk,
      encoding: encoding,
      isBuf: isBuf,
      callback: cb,
      next: null
    };
    if (last) {
      last.next = state.lastBufferedRequest;
    } else {
      state.bufferedRequest = state.lastBufferedRequest;
    }
    state.bufferedRequestCount += 1;
  } else {
    doWrite(stream, state, false, len, chunk, encoding, cb);
  }

  return ret;
}

function doWrite(stream, state, writev, len, chunk, encoding, cb) {
  state.writelen = len;
  state.writecb = cb;
  state.writing = true;
  state.sync = true;
  if (writev) stream._writev(chunk, state.onwrite);else stream._write(chunk, encoding, state.onwrite);
  state.sync = false;
}

function onwriteError(stream, state, sync, er, cb) {
  --state.pendingcb;

  if (sync) {
    // defer the callback if we are being called synchronously
    // to avoid piling up things on the stack
    pna.nextTick(cb, er);
    // this can emit finish, and it will always happen
    // after error
    pna.nextTick(finishMaybe, stream, state);
    stream._writableState.errorEmitted = true;
    stream.emit('error', er);
  } else {
    // the caller expect this to happen before if
    // it is async
    cb(er);
    stream._writableState.errorEmitted = true;
    stream.emit('error', er);
    // this can emit finish, but finish must
    // always follow error
    finishMaybe(stream, state);
  }
}

function onwriteStateUpdate(state) {
  state.writing = false;
  state.writecb = null;
  state.length -= state.writelen;
  state.writelen = 0;
}

function onwrite(stream, er) {
  var state = stream._writableState;
  var sync = state.sync;
  var cb = state.writecb;

  onwriteStateUpdate(state);

  if (er) onwriteError(stream, state, sync, er, cb);else {
    // Check if we're actually ready to finish, but don't emit yet
    var finished = needFinish(state);

    if (!finished && !state.corked && !state.bufferProcessing && state.bufferedRequest) {
      clearBuffer(stream, state);
    }

    if (sync) {
      /*<replacement>*/
      asyncWrite(afterWrite, stream, state, finished, cb);
      /*</replacement>*/
    } else {
      afterWrite(stream, state, finished, cb);
    }
  }
}

function afterWrite(stream, state, finished, cb) {
  if (!finished) onwriteDrain(stream, state);
  state.pendingcb--;
  cb();
  finishMaybe(stream, state);
}

// Must force callback to be called on nextTick, so that we don't
// emit 'drain' before the write() consumer gets the 'false' return
// value, and has a chance to attach a 'drain' listener.
function onwriteDrain(stream, state) {
  if (state.length === 0 && state.needDrain) {
    state.needDrain = false;
    stream.emit('drain');
  }
}

// if there's something in the buffer waiting, then process it
function clearBuffer(stream, state) {
  state.bufferProcessing = true;
  var entry = state.bufferedRequest;

  if (stream._writev && entry && entry.next) {
    // Fast case, write everything using _writev()
    var l = state.bufferedRequestCount;
    var buffer = new Array(l);
    var holder = state.corkedRequestsFree;
    holder.entry = entry;

    var count = 0;
    var allBuffers = true;
    while (entry) {
      buffer[count] = entry;
      if (!entry.isBuf) allBuffers = false;
      entry = entry.next;
      count += 1;
    }
    buffer.allBuffers = allBuffers;

    doWrite(stream, state, true, state.length, buffer, '', holder.finish);

    // doWrite is almost always async, defer these to save a bit of time
    // as the hot path ends with doWrite
    state.pendingcb++;
    state.lastBufferedRequest = null;
    if (holder.next) {
      state.corkedRequestsFree = holder.next;
      holder.next = null;
    } else {
      state.corkedRequestsFree = new CorkedRequest(state);
    }
    state.bufferedRequestCount = 0;
  } else {
    // Slow case, write chunks one-by-one
    while (entry) {
      var chunk = entry.chunk;
      var encoding = entry.encoding;
      var cb = entry.callback;
      var len = state.objectMode ? 1 : chunk.length;

      doWrite(stream, state, false, len, chunk, encoding, cb);
      entry = entry.next;
      state.bufferedRequestCount--;
      // if we didn't call the onwrite immediately, then
      // it means that we need to wait until it does.
      // also, that means that the chunk and cb are currently
      // being processed, so move the buffer counter past them.
      if (state.writing) {
        break;
      }
    }

    if (entry === null) state.lastBufferedRequest = null;
  }

  state.bufferedRequest = entry;
  state.bufferProcessing = false;
}

Writable.prototype._write = function (chunk, encoding, cb) {
  cb(new Error('_write() is not implemented'));
};

Writable.prototype._writev = null;

Writable.prototype.end = function (chunk, encoding, cb) {
  var state = this._writableState;

  if (typeof chunk === 'function') {
    cb = chunk;
    chunk = null;
    encoding = null;
  } else if (typeof encoding === 'function') {
    cb = encoding;
    encoding = null;
  }

  if (chunk !== null && chunk !== undefined) this.write(chunk, encoding);

  // .end() fully uncorks
  if (state.corked) {
    state.corked = 1;
    this.uncork();
  }

  // ignore unnecessary end() calls.
  if (!state.ending && !state.finished) endWritable(this, state, cb);
};

function needFinish(state) {
  return state.ending && state.length === 0 && state.bufferedRequest === null && !state.finished && !state.writing;
}
function callFinal(stream, state) {
  stream._final(function (err) {
    state.pendingcb--;
    if (err) {
      stream.emit('error', err);
    }
    state.prefinished = true;
    stream.emit('prefinish');
    finishMaybe(stream, state);
  });
}
function prefinish(stream, state) {
  if (!state.prefinished && !state.finalCalled) {
    if (typeof stream._final === 'function') {
      state.pendingcb++;
      state.finalCalled = true;
      pna.nextTick(callFinal, stream, state);
    } else {
      state.prefinished = true;
      stream.emit('prefinish');
    }
  }
}

function finishMaybe(stream, state) {
  var need = needFinish(state);
  if (need) {
    prefinish(stream, state);
    if (state.pendingcb === 0) {
      state.finished = true;
      stream.emit('finish');
    }
  }
  return need;
}

function endWritable(stream, state, cb) {
  state.ending = true;
  finishMaybe(stream, state);
  if (cb) {
    if (state.finished) pna.nextTick(cb);else stream.once('finish', cb);
  }
  state.ended = true;
  stream.writable = false;
}

function onCorkedFinish(corkReq, state, err) {
  var entry = corkReq.entry;
  corkReq.entry = null;
  while (entry) {
    var cb = entry.callback;
    state.pendingcb--;
    cb(err);
    entry = entry.next;
  }
  if (state.corkedRequestsFree) {
    state.corkedRequestsFree.next = corkReq;
  } else {
    state.corkedRequestsFree = corkReq;
  }
}

Object.defineProperty(Writable.prototype, 'destroyed', {
  get: function () {
    if (this._writableState === undefined) {
      return false;
    }
    return this._writableState.destroyed;
  },
  set: function (value) {
    // we ignore the value if the stream
    // has not been initialized yet
    if (!this._writableState) {
      return;
    }

    // backward compatibility, the user is explicitly
    // managing destroyed
    this._writableState.destroyed = value;
  }
});

Writable.prototype.destroy = destroyImpl.destroy;
Writable.prototype._undestroy = destroyImpl.undestroy;
Writable.prototype._destroy = function (err, cb) {
  this.end();
  cb(err);
};
}).call(this,require('_process'),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {},require("timers").setImmediate)

},{"./_stream_duplex":70,"./internal/streams/destroy":76,"./internal/streams/stream":77,"_process":66,"core-util-is":26,"inherits":31,"process-nextick-args":65,"safe-buffer":79,"timers":85,"util-deprecate":89}],75:[function(require,module,exports){
'use strict';

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var Buffer = require('safe-buffer').Buffer;
var util = require('util');

function copyBuffer(src, target, offset) {
  src.copy(target, offset);
}

module.exports = function () {
  function BufferList() {
    _classCallCheck(this, BufferList);

    this.head = null;
    this.tail = null;
    this.length = 0;
  }

  BufferList.prototype.push = function push(v) {
    var entry = { data: v, next: null };
    if (this.length > 0) this.tail.next = entry;else this.head = entry;
    this.tail = entry;
    ++this.length;
  };

  BufferList.prototype.unshift = function unshift(v) {
    var entry = { data: v, next: this.head };
    if (this.length === 0) this.tail = entry;
    this.head = entry;
    ++this.length;
  };

  BufferList.prototype.shift = function shift() {
    if (this.length === 0) return;
    var ret = this.head.data;
    if (this.length === 1) this.head = this.tail = null;else this.head = this.head.next;
    --this.length;
    return ret;
  };

  BufferList.prototype.clear = function clear() {
    this.head = this.tail = null;
    this.length = 0;
  };

  BufferList.prototype.join = function join(s) {
    if (this.length === 0) return '';
    var p = this.head;
    var ret = '' + p.data;
    while (p = p.next) {
      ret += s + p.data;
    }return ret;
  };

  BufferList.prototype.concat = function concat(n) {
    if (this.length === 0) return Buffer.alloc(0);
    if (this.length === 1) return this.head.data;
    var ret = Buffer.allocUnsafe(n >>> 0);
    var p = this.head;
    var i = 0;
    while (p) {
      copyBuffer(p.data, ret, i);
      i += p.data.length;
      p = p.next;
    }
    return ret;
  };

  return BufferList;
}();

if (util && util.inspect && util.inspect.custom) {
  module.exports.prototype[util.inspect.custom] = function () {
    var obj = util.inspect({ length: this.length });
    return this.constructor.name + ' ' + obj;
  };
}
},{"safe-buffer":79,"util":21}],76:[function(require,module,exports){
'use strict';

/*<replacement>*/

var pna = require('process-nextick-args');
/*</replacement>*/

// undocumented cb() API, needed for core, not for public API
function destroy(err, cb) {
  var _this = this;

  var readableDestroyed = this._readableState && this._readableState.destroyed;
  var writableDestroyed = this._writableState && this._writableState.destroyed;

  if (readableDestroyed || writableDestroyed) {
    if (cb) {
      cb(err);
    } else if (err && (!this._writableState || !this._writableState.errorEmitted)) {
      pna.nextTick(emitErrorNT, this, err);
    }
    return this;
  }

  // we set destroyed to true before firing error callbacks in order
  // to make it re-entrance safe in case destroy() is called within callbacks

  if (this._readableState) {
    this._readableState.destroyed = true;
  }

  // if this is a duplex stream mark the writable part as destroyed as well
  if (this._writableState) {
    this._writableState.destroyed = true;
  }

  this._destroy(err || null, function (err) {
    if (!cb && err) {
      pna.nextTick(emitErrorNT, _this, err);
      if (_this._writableState) {
        _this._writableState.errorEmitted = true;
      }
    } else if (cb) {
      cb(err);
    }
  });

  return this;
}

function undestroy() {
  if (this._readableState) {
    this._readableState.destroyed = false;
    this._readableState.reading = false;
    this._readableState.ended = false;
    this._readableState.endEmitted = false;
  }

  if (this._writableState) {
    this._writableState.destroyed = false;
    this._writableState.ended = false;
    this._writableState.ending = false;
    this._writableState.finished = false;
    this._writableState.errorEmitted = false;
  }
}

function emitErrorNT(self, err) {
  self.emit('error', err);
}

module.exports = {
  destroy: destroy,
  undestroy: undestroy
};
},{"process-nextick-args":65}],77:[function(require,module,exports){
module.exports = require('events').EventEmitter;

},{"events":27}],78:[function(require,module,exports){
exports = module.exports = require('./lib/_stream_readable.js');
exports.Stream = exports;
exports.Readable = exports;
exports.Writable = require('./lib/_stream_writable.js');
exports.Duplex = require('./lib/_stream_duplex.js');
exports.Transform = require('./lib/_stream_transform.js');
exports.PassThrough = require('./lib/_stream_passthrough.js');

},{"./lib/_stream_duplex.js":70,"./lib/_stream_passthrough.js":71,"./lib/_stream_readable.js":72,"./lib/_stream_transform.js":73,"./lib/_stream_writable.js":74}],79:[function(require,module,exports){
/* eslint-disable node/no-deprecated-api */
var buffer = require('buffer')
var Buffer = buffer.Buffer

// alternative to using Object.keys for old browsers
function copyProps (src, dst) {
  for (var key in src) {
    dst[key] = src[key]
  }
}
if (Buffer.from && Buffer.alloc && Buffer.allocUnsafe && Buffer.allocUnsafeSlow) {
  module.exports = buffer
} else {
  // Copy properties from require('buffer')
  copyProps(buffer, exports)
  exports.Buffer = SafeBuffer
}

function SafeBuffer (arg, encodingOrOffset, length) {
  return Buffer(arg, encodingOrOffset, length)
}

// Copy static methods from Buffer
copyProps(Buffer, SafeBuffer)

SafeBuffer.from = function (arg, encodingOrOffset, length) {
  if (typeof arg === 'number') {
    throw new TypeError('Argument must not be a number')
  }
  return Buffer(arg, encodingOrOffset, length)
}

SafeBuffer.alloc = function (size, fill, encoding) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  var buf = Buffer(size)
  if (fill !== undefined) {
    if (typeof encoding === 'string') {
      buf.fill(fill, encoding)
    } else {
      buf.fill(fill)
    }
  } else {
    buf.fill(0)
  }
  return buf
}

SafeBuffer.allocUnsafe = function (size) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  return Buffer(size)
}

SafeBuffer.allocUnsafeSlow = function (size) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  return buffer.SlowBuffer(size)
}

},{"buffer":23}],80:[function(require,module,exports){
(function (global){
var ClientRequest = require('./lib/request')
var response = require('./lib/response')
var extend = require('xtend')
var statusCodes = require('builtin-status-codes')
var url = require('url')

var http = exports

http.request = function (opts, cb) {
	if (typeof opts === 'string')
		opts = url.parse(opts)
	else
		opts = extend(opts)

	// Normally, the page is loaded from http or https, so not specifying a protocol
	// will result in a (valid) protocol-relative url. However, this won't work if
	// the protocol is something else, like 'file:'
	var defaultProtocol = global.location.protocol.search(/^https?:$/) === -1 ? 'http:' : ''

	var protocol = opts.protocol || defaultProtocol
	var host = opts.hostname || opts.host
	var port = opts.port
	var path = opts.path || '/'

	// Necessary for IPv6 addresses
	if (host && host.indexOf(':') !== -1)
		host = '[' + host + ']'

	// This may be a relative url. The browser should always be able to interpret it correctly.
	opts.url = (host ? (protocol + '//' + host) : '') + (port ? ':' + port : '') + path
	opts.method = (opts.method || 'GET').toUpperCase()
	opts.headers = opts.headers || {}

	// Also valid opts.auth, opts.mode

	var req = new ClientRequest(opts)
	if (cb)
		req.on('response', cb)
	return req
}

http.get = function get (opts, cb) {
	var req = http.request(opts, cb)
	req.end()
	return req
}

http.ClientRequest = ClientRequest
http.IncomingMessage = response.IncomingMessage

http.Agent = function () {}
http.Agent.defaultMaxSockets = 4

http.globalAgent = new http.Agent()

http.STATUS_CODES = statusCodes

http.METHODS = [
	'CHECKOUT',
	'CONNECT',
	'COPY',
	'DELETE',
	'GET',
	'HEAD',
	'LOCK',
	'M-SEARCH',
	'MERGE',
	'MKACTIVITY',
	'MKCOL',
	'MOVE',
	'NOTIFY',
	'OPTIONS',
	'PATCH',
	'POST',
	'PROPFIND',
	'PROPPATCH',
	'PURGE',
	'PUT',
	'REPORT',
	'SEARCH',
	'SUBSCRIBE',
	'TRACE',
	'UNLOCK',
	'UNSUBSCRIBE'
]
}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{"./lib/request":82,"./lib/response":83,"builtin-status-codes":24,"url":87,"xtend":90}],81:[function(require,module,exports){
(function (global){
exports.fetch = isFunction(global.fetch) && isFunction(global.ReadableStream)

exports.writableStream = isFunction(global.WritableStream)

exports.abortController = isFunction(global.AbortController)

exports.blobConstructor = false
try {
	new Blob([new ArrayBuffer(1)])
	exports.blobConstructor = true
} catch (e) {}

// The xhr request to example.com may violate some restrictive CSP configurations,
// so if we're running in a browser that supports `fetch`, avoid calling getXHR()
// and assume support for certain features below.
var xhr
function getXHR () {
	// Cache the xhr value
	if (xhr !== undefined) return xhr

	if (global.XMLHttpRequest) {
		xhr = new global.XMLHttpRequest()
		// If XDomainRequest is available (ie only, where xhr might not work
		// cross domain), use the page location. Otherwise use example.com
		// Note: this doesn't actually make an http request.
		try {
			xhr.open('GET', global.XDomainRequest ? '/' : 'https://example.com')
		} catch(e) {
			xhr = null
		}
	} else {
		// Service workers don't have XHR
		xhr = null
	}
	return xhr
}

function checkTypeSupport (type) {
	var xhr = getXHR()
	if (!xhr) return false
	try {
		xhr.responseType = type
		return xhr.responseType === type
	} catch (e) {}
	return false
}

// For some strange reason, Safari 7.0 reports typeof global.ArrayBuffer === 'object'.
// Safari 7.1 appears to have fixed this bug.
var haveArrayBuffer = typeof global.ArrayBuffer !== 'undefined'
var haveSlice = haveArrayBuffer && isFunction(global.ArrayBuffer.prototype.slice)

// If fetch is supported, then arraybuffer will be supported too. Skip calling
// checkTypeSupport(), since that calls getXHR().
exports.arraybuffer = exports.fetch || (haveArrayBuffer && checkTypeSupport('arraybuffer'))

// These next two tests unavoidably show warnings in Chrome. Since fetch will always
// be used if it's available, just return false for these to avoid the warnings.
exports.msstream = !exports.fetch && haveSlice && checkTypeSupport('ms-stream')
exports.mozchunkedarraybuffer = !exports.fetch && haveArrayBuffer &&
	checkTypeSupport('moz-chunked-arraybuffer')

// If fetch is supported, then overrideMimeType will be supported too. Skip calling
// getXHR().
exports.overrideMimeType = exports.fetch || (getXHR() ? isFunction(getXHR().overrideMimeType) : false)

exports.vbArray = isFunction(global.VBArray)

function isFunction (value) {
	return typeof value === 'function'
}

xhr = null // Help gc

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{}],82:[function(require,module,exports){
(function (process,global,Buffer){
var capability = require('./capability')
var inherits = require('inherits')
var response = require('./response')
var stream = require('readable-stream')
var toArrayBuffer = require('to-arraybuffer')

var IncomingMessage = response.IncomingMessage
var rStates = response.readyStates

function decideMode (preferBinary, useFetch) {
	if (capability.fetch && useFetch) {
		return 'fetch'
	} else if (capability.mozchunkedarraybuffer) {
		return 'moz-chunked-arraybuffer'
	} else if (capability.msstream) {
		return 'ms-stream'
	} else if (capability.arraybuffer && preferBinary) {
		return 'arraybuffer'
	} else if (capability.vbArray && preferBinary) {
		return 'text:vbarray'
	} else {
		return 'text'
	}
}

var ClientRequest = module.exports = function (opts) {
	var self = this
	stream.Writable.call(self)

	self._opts = opts
	self._body = []
	self._headers = {}
	if (opts.auth)
		self.setHeader('Authorization', 'Basic ' + new Buffer(opts.auth).toString('base64'))
	Object.keys(opts.headers).forEach(function (name) {
		self.setHeader(name, opts.headers[name])
	})

	var preferBinary
	var useFetch = true
	if (opts.mode === 'disable-fetch' || ('requestTimeout' in opts && !capability.abortController)) {
		// If the use of XHR should be preferred. Not typically needed.
		useFetch = false
		preferBinary = true
	} else if (opts.mode === 'prefer-streaming') {
		// If streaming is a high priority but binary compatibility and
		// the accuracy of the 'content-type' header aren't
		preferBinary = false
	} else if (opts.mode === 'allow-wrong-content-type') {
		// If streaming is more important than preserving the 'content-type' header
		preferBinary = !capability.overrideMimeType
	} else if (!opts.mode || opts.mode === 'default' || opts.mode === 'prefer-fast') {
		// Use binary if text streaming may corrupt data or the content-type header, or for speed
		preferBinary = true
	} else {
		throw new Error('Invalid value for opts.mode')
	}
	self._mode = decideMode(preferBinary, useFetch)
	self._fetchTimer = null

	self.on('finish', function () {
		self._onFinish()
	})
}

inherits(ClientRequest, stream.Writable)

ClientRequest.prototype.setHeader = function (name, value) {
	var self = this
	var lowerName = name.toLowerCase()
	// This check is not necessary, but it prevents warnings from browsers about setting unsafe
	// headers. To be honest I'm not entirely sure hiding these warnings is a good thing, but
	// http-browserify did it, so I will too.
	if (unsafeHeaders.indexOf(lowerName) !== -1)
		return

	self._headers[lowerName] = {
		name: name,
		value: value
	}
}

ClientRequest.prototype.getHeader = function (name) {
	var header = this._headers[name.toLowerCase()]
	if (header)
		return header.value
	return null
}

ClientRequest.prototype.removeHeader = function (name) {
	var self = this
	delete self._headers[name.toLowerCase()]
}

ClientRequest.prototype._onFinish = function () {
	var self = this

	if (self._destroyed)
		return
	var opts = self._opts

	var headersObj = self._headers
	var body = null
	if (opts.method !== 'GET' && opts.method !== 'HEAD') {
		if (capability.arraybuffer) {
			body = toArrayBuffer(Buffer.concat(self._body))
		} else if (capability.blobConstructor) {
			body = new global.Blob(self._body.map(function (buffer) {
				return toArrayBuffer(buffer)
			}), {
				type: (headersObj['content-type'] || {}).value || ''
			})
		} else {
			// get utf8 string
			body = Buffer.concat(self._body).toString()
		}
	}

	// create flattened list of headers
	var headersList = []
	Object.keys(headersObj).forEach(function (keyName) {
		var name = headersObj[keyName].name
		var value = headersObj[keyName].value
		if (Array.isArray(value)) {
			value.forEach(function (v) {
				headersList.push([name, v])
			})
		} else {
			headersList.push([name, value])
		}
	})

	if (self._mode === 'fetch') {
		var signal = null
		var fetchTimer = null
		if (capability.abortController) {
			var controller = new AbortController()
			signal = controller.signal
			self._fetchAbortController = controller

			if ('requestTimeout' in opts && opts.requestTimeout !== 0) {
				self._fetchTimer = global.setTimeout(function () {
					self.emit('requestTimeout')
					if (self._fetchAbortController)
						self._fetchAbortController.abort()
				}, opts.requestTimeout)
			}
		}

		global.fetch(self._opts.url, {
			method: self._opts.method,
			headers: headersList,
			body: body || undefined,
			mode: 'cors',
			credentials: opts.withCredentials ? 'include' : 'same-origin',
			signal: signal
		}).then(function (response) {
			self._fetchResponse = response
			self._connect()
		}, function (reason) {
			global.clearTimeout(self._fetchTimer)
			if (!self._destroyed)
				self.emit('error', reason)
		})
	} else {
		var xhr = self._xhr = new global.XMLHttpRequest()
		try {
			xhr.open(self._opts.method, self._opts.url, true)
		} catch (err) {
			process.nextTick(function () {
				self.emit('error', err)
			})
			return
		}

		// Can't set responseType on really old browsers
		if ('responseType' in xhr)
			xhr.responseType = self._mode.split(':')[0]

		if ('withCredentials' in xhr)
			xhr.withCredentials = !!opts.withCredentials

		if (self._mode === 'text' && 'overrideMimeType' in xhr)
			xhr.overrideMimeType('text/plain; charset=x-user-defined')

		if ('requestTimeout' in opts) {
			xhr.timeout = opts.requestTimeout
			xhr.ontimeout = function () {
				self.emit('requestTimeout')
			}
		}

		headersList.forEach(function (header) {
			xhr.setRequestHeader(header[0], header[1])
		})

		self._response = null
		xhr.onreadystatechange = function () {
			switch (xhr.readyState) {
				case rStates.LOADING:
				case rStates.DONE:
					self._onXHRProgress()
					break
			}
		}
		// Necessary for streaming in Firefox, since xhr.response is ONLY defined
		// in onprogress, not in onreadystatechange with xhr.readyState = 3
		if (self._mode === 'moz-chunked-arraybuffer') {
			xhr.onprogress = function () {
				self._onXHRProgress()
			}
		}

		xhr.onerror = function () {
			if (self._destroyed)
				return
			self.emit('error', new Error('XHR error'))
		}

		try {
			xhr.send(body)
		} catch (err) {
			process.nextTick(function () {
				self.emit('error', err)
			})
			return
		}
	}
}

/**
 * Checks if xhr.status is readable and non-zero, indicating no error.
 * Even though the spec says it should be available in readyState 3,
 * accessing it throws an exception in IE8
 */
function statusValid (xhr) {
	try {
		var status = xhr.status
		return (status !== null && status !== 0)
	} catch (e) {
		return false
	}
}

ClientRequest.prototype._onXHRProgress = function () {
	var self = this

	if (!statusValid(self._xhr) || self._destroyed)
		return

	if (!self._response)
		self._connect()

	self._response._onXHRProgress()
}

ClientRequest.prototype._connect = function () {
	var self = this

	if (self._destroyed)
		return

	self._response = new IncomingMessage(self._xhr, self._fetchResponse, self._mode, self._fetchTimer)
	self._response.on('error', function(err) {
		self.emit('error', err)
	})

	self.emit('response', self._response)
}

ClientRequest.prototype._write = function (chunk, encoding, cb) {
	var self = this

	self._body.push(chunk)
	cb()
}

ClientRequest.prototype.abort = ClientRequest.prototype.destroy = function () {
	var self = this
	self._destroyed = true
	global.clearTimeout(self._fetchTimer)
	if (self._response)
		self._response._destroyed = true
	if (self._xhr)
		self._xhr.abort()
	else if (self._fetchAbortController)
		self._fetchAbortController.abort()
}

ClientRequest.prototype.end = function (data, encoding, cb) {
	var self = this
	if (typeof data === 'function') {
		cb = data
		data = undefined
	}

	stream.Writable.prototype.end.call(self, data, encoding, cb)
}

ClientRequest.prototype.flushHeaders = function () {}
ClientRequest.prototype.setTimeout = function () {}
ClientRequest.prototype.setNoDelay = function () {}
ClientRequest.prototype.setSocketKeepAlive = function () {}

// Taken from http://www.w3.org/TR/XMLHttpRequest/#the-setrequestheader%28%29-method
var unsafeHeaders = [
	'accept-charset',
	'accept-encoding',
	'access-control-request-headers',
	'access-control-request-method',
	'connection',
	'content-length',
	'cookie',
	'cookie2',
	'date',
	'dnt',
	'expect',
	'host',
	'keep-alive',
	'origin',
	'referer',
	'te',
	'trailer',
	'transfer-encoding',
	'upgrade',
	'via'
]

}).call(this,require('_process'),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {},require("buffer").Buffer)

},{"./capability":81,"./response":83,"_process":66,"buffer":23,"inherits":31,"readable-stream":78,"to-arraybuffer":86}],83:[function(require,module,exports){
(function (process,global,Buffer){
var capability = require('./capability')
var inherits = require('inherits')
var stream = require('readable-stream')

var rStates = exports.readyStates = {
	UNSENT: 0,
	OPENED: 1,
	HEADERS_RECEIVED: 2,
	LOADING: 3,
	DONE: 4
}

var IncomingMessage = exports.IncomingMessage = function (xhr, response, mode, fetchTimer) {
	var self = this
	stream.Readable.call(self)

	self._mode = mode
	self.headers = {}
	self.rawHeaders = []
	self.trailers = {}
	self.rawTrailers = []

	// Fake the 'close' event, but only once 'end' fires
	self.on('end', function () {
		// The nextTick is necessary to prevent the 'request' module from causing an infinite loop
		process.nextTick(function () {
			self.emit('close')
		})
	})

	if (mode === 'fetch') {
		self._fetchResponse = response

		self.url = response.url
		self.statusCode = response.status
		self.statusMessage = response.statusText
		
		response.headers.forEach(function (header, key){
			self.headers[key.toLowerCase()] = header
			self.rawHeaders.push(key, header)
		})

		if (capability.writableStream) {
			var writable = new WritableStream({
				write: function (chunk) {
					return new Promise(function (resolve, reject) {
						if (self._destroyed) {
							reject()
						} else if(self.push(new Buffer(chunk))) {
							resolve()
						} else {
							self._resumeFetch = resolve
						}
					})
				},
				close: function () {
					global.clearTimeout(fetchTimer)
					if (!self._destroyed)
						self.push(null)
				},
				abort: function (err) {
					if (!self._destroyed)
						self.emit('error', err)
				}
			})

			try {
				response.body.pipeTo(writable).catch(function (err) {
					global.clearTimeout(fetchTimer)
					if (!self._destroyed)
						self.emit('error', err)
				})
				return
			} catch (e) {} // pipeTo method isn't defined. Can't find a better way to feature test this
		}
		// fallback for when writableStream or pipeTo aren't available
		var reader = response.body.getReader()
		function read () {
			reader.read().then(function (result) {
				if (self._destroyed)
					return
				if (result.done) {
					global.clearTimeout(fetchTimer)
					self.push(null)
					return
				}
				self.push(new Buffer(result.value))
				read()
			}).catch(function (err) {
				global.clearTimeout(fetchTimer)
				if (!self._destroyed)
					self.emit('error', err)
			})
		}
		read()
	} else {
		self._xhr = xhr
		self._pos = 0

		self.url = xhr.responseURL
		self.statusCode = xhr.status
		self.statusMessage = xhr.statusText
		var headers = xhr.getAllResponseHeaders().split(/\r?\n/)
		headers.forEach(function (header) {
			var matches = header.match(/^([^:]+):\s*(.*)/)
			if (matches) {
				var key = matches[1].toLowerCase()
				if (key === 'set-cookie') {
					if (self.headers[key] === undefined) {
						self.headers[key] = []
					}
					self.headers[key].push(matches[2])
				} else if (self.headers[key] !== undefined) {
					self.headers[key] += ', ' + matches[2]
				} else {
					self.headers[key] = matches[2]
				}
				self.rawHeaders.push(matches[1], matches[2])
			}
		})

		self._charset = 'x-user-defined'
		if (!capability.overrideMimeType) {
			var mimeType = self.rawHeaders['mime-type']
			if (mimeType) {
				var charsetMatch = mimeType.match(/;\s*charset=([^;])(;|$)/)
				if (charsetMatch) {
					self._charset = charsetMatch[1].toLowerCase()
				}
			}
			if (!self._charset)
				self._charset = 'utf-8' // best guess
		}
	}
}

inherits(IncomingMessage, stream.Readable)

IncomingMessage.prototype._read = function () {
	var self = this

	var resolve = self._resumeFetch
	if (resolve) {
		self._resumeFetch = null
		resolve()
	}
}

IncomingMessage.prototype._onXHRProgress = function () {
	var self = this

	var xhr = self._xhr

	var response = null
	switch (self._mode) {
		case 'text:vbarray': // For IE9
			if (xhr.readyState !== rStates.DONE)
				break
			try {
				// This fails in IE8
				response = new global.VBArray(xhr.responseBody).toArray()
			} catch (e) {}
			if (response !== null) {
				self.push(new Buffer(response))
				break
			}
			// Falls through in IE8	
		case 'text':
			try { // This will fail when readyState = 3 in IE9. Switch mode and wait for readyState = 4
				response = xhr.responseText
			} catch (e) {
				self._mode = 'text:vbarray'
				break
			}
			if (response.length > self._pos) {
				var newData = response.substr(self._pos)
				if (self._charset === 'x-user-defined') {
					var buffer = new Buffer(newData.length)
					for (var i = 0; i < newData.length; i++)
						buffer[i] = newData.charCodeAt(i) & 0xff

					self.push(buffer)
				} else {
					self.push(newData, self._charset)
				}
				self._pos = response.length
			}
			break
		case 'arraybuffer':
			if (xhr.readyState !== rStates.DONE || !xhr.response)
				break
			response = xhr.response
			self.push(new Buffer(new Uint8Array(response)))
			break
		case 'moz-chunked-arraybuffer': // take whole
			response = xhr.response
			if (xhr.readyState !== rStates.LOADING || !response)
				break
			self.push(new Buffer(new Uint8Array(response)))
			break
		case 'ms-stream':
			response = xhr.response
			if (xhr.readyState !== rStates.LOADING)
				break
			var reader = new global.MSStreamReader()
			reader.onprogress = function () {
				if (reader.result.byteLength > self._pos) {
					self.push(new Buffer(new Uint8Array(reader.result.slice(self._pos))))
					self._pos = reader.result.byteLength
				}
			}
			reader.onload = function () {
				self.push(null)
			}
			// reader.onerror = ??? // TODO: this
			reader.readAsArrayBuffer(response)
			break
	}

	// The ms-stream case handles end separately in reader.onload()
	if (self._xhr.readyState === rStates.DONE && self._mode !== 'ms-stream') {
		self.push(null)
	}
}

}).call(this,require('_process'),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {},require("buffer").Buffer)

},{"./capability":81,"_process":66,"buffer":23,"inherits":31,"readable-stream":78}],84:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

'use strict';

/*<replacement>*/

var Buffer = require('safe-buffer').Buffer;
/*</replacement>*/

var isEncoding = Buffer.isEncoding || function (encoding) {
  encoding = '' + encoding;
  switch (encoding && encoding.toLowerCase()) {
    case 'hex':case 'utf8':case 'utf-8':case 'ascii':case 'binary':case 'base64':case 'ucs2':case 'ucs-2':case 'utf16le':case 'utf-16le':case 'raw':
      return true;
    default:
      return false;
  }
};

function _normalizeEncoding(enc) {
  if (!enc) return 'utf8';
  var retried;
  while (true) {
    switch (enc) {
      case 'utf8':
      case 'utf-8':
        return 'utf8';
      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return 'utf16le';
      case 'latin1':
      case 'binary':
        return 'latin1';
      case 'base64':
      case 'ascii':
      case 'hex':
        return enc;
      default:
        if (retried) return; // undefined
        enc = ('' + enc).toLowerCase();
        retried = true;
    }
  }
};

// Do not cache `Buffer.isEncoding` when checking encoding names as some
// modules monkey-patch it to support additional encodings
function normalizeEncoding(enc) {
  var nenc = _normalizeEncoding(enc);
  if (typeof nenc !== 'string' && (Buffer.isEncoding === isEncoding || !isEncoding(enc))) throw new Error('Unknown encoding: ' + enc);
  return nenc || enc;
}

// StringDecoder provides an interface for efficiently splitting a series of
// buffers into a series of JS strings without breaking apart multi-byte
// characters.
exports.StringDecoder = StringDecoder;
function StringDecoder(encoding) {
  this.encoding = normalizeEncoding(encoding);
  var nb;
  switch (this.encoding) {
    case 'utf16le':
      this.text = utf16Text;
      this.end = utf16End;
      nb = 4;
      break;
    case 'utf8':
      this.fillLast = utf8FillLast;
      nb = 4;
      break;
    case 'base64':
      this.text = base64Text;
      this.end = base64End;
      nb = 3;
      break;
    default:
      this.write = simpleWrite;
      this.end = simpleEnd;
      return;
  }
  this.lastNeed = 0;
  this.lastTotal = 0;
  this.lastChar = Buffer.allocUnsafe(nb);
}

StringDecoder.prototype.write = function (buf) {
  if (buf.length === 0) return '';
  var r;
  var i;
  if (this.lastNeed) {
    r = this.fillLast(buf);
    if (r === undefined) return '';
    i = this.lastNeed;
    this.lastNeed = 0;
  } else {
    i = 0;
  }
  if (i < buf.length) return r ? r + this.text(buf, i) : this.text(buf, i);
  return r || '';
};

StringDecoder.prototype.end = utf8End;

// Returns only complete characters in a Buffer
StringDecoder.prototype.text = utf8Text;

// Attempts to complete a partial non-UTF-8 character using bytes from a Buffer
StringDecoder.prototype.fillLast = function (buf) {
  if (this.lastNeed <= buf.length) {
    buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, this.lastNeed);
    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
  }
  buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, buf.length);
  this.lastNeed -= buf.length;
};

// Checks the type of a UTF-8 byte, whether it's ASCII, a leading byte, or a
// continuation byte. If an invalid byte is detected, -2 is returned.
function utf8CheckByte(byte) {
  if (byte <= 0x7F) return 0;else if (byte >> 5 === 0x06) return 2;else if (byte >> 4 === 0x0E) return 3;else if (byte >> 3 === 0x1E) return 4;
  return byte >> 6 === 0x02 ? -1 : -2;
}

// Checks at most 3 bytes at the end of a Buffer in order to detect an
// incomplete multi-byte UTF-8 character. The total number of bytes (2, 3, or 4)
// needed to complete the UTF-8 character (if applicable) are returned.
function utf8CheckIncomplete(self, buf, i) {
  var j = buf.length - 1;
  if (j < i) return 0;
  var nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) self.lastNeed = nb - 1;
    return nb;
  }
  if (--j < i || nb === -2) return 0;
  nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) self.lastNeed = nb - 2;
    return nb;
  }
  if (--j < i || nb === -2) return 0;
  nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) {
      if (nb === 2) nb = 0;else self.lastNeed = nb - 3;
    }
    return nb;
  }
  return 0;
}

// Validates as many continuation bytes for a multi-byte UTF-8 character as
// needed or are available. If we see a non-continuation byte where we expect
// one, we "replace" the validated continuation bytes we've seen so far with
// a single UTF-8 replacement character ('\ufffd'), to match v8's UTF-8 decoding
// behavior. The continuation byte check is included three times in the case
// where all of the continuation bytes for a character exist in the same buffer.
// It is also done this way as a slight performance increase instead of using a
// loop.
function utf8CheckExtraBytes(self, buf, p) {
  if ((buf[0] & 0xC0) !== 0x80) {
    self.lastNeed = 0;
    return '\ufffd';
  }
  if (self.lastNeed > 1 && buf.length > 1) {
    if ((buf[1] & 0xC0) !== 0x80) {
      self.lastNeed = 1;
      return '\ufffd';
    }
    if (self.lastNeed > 2 && buf.length > 2) {
      if ((buf[2] & 0xC0) !== 0x80) {
        self.lastNeed = 2;
        return '\ufffd';
      }
    }
  }
}

// Attempts to complete a multi-byte UTF-8 character using bytes from a Buffer.
function utf8FillLast(buf) {
  var p = this.lastTotal - this.lastNeed;
  var r = utf8CheckExtraBytes(this, buf, p);
  if (r !== undefined) return r;
  if (this.lastNeed <= buf.length) {
    buf.copy(this.lastChar, p, 0, this.lastNeed);
    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
  }
  buf.copy(this.lastChar, p, 0, buf.length);
  this.lastNeed -= buf.length;
}

// Returns all complete UTF-8 characters in a Buffer. If the Buffer ended on a
// partial character, the character's bytes are buffered until the required
// number of bytes are available.
function utf8Text(buf, i) {
  var total = utf8CheckIncomplete(this, buf, i);
  if (!this.lastNeed) return buf.toString('utf8', i);
  this.lastTotal = total;
  var end = buf.length - (total - this.lastNeed);
  buf.copy(this.lastChar, 0, end);
  return buf.toString('utf8', i, end);
}

// For UTF-8, a replacement character is added when ending on a partial
// character.
function utf8End(buf) {
  var r = buf && buf.length ? this.write(buf) : '';
  if (this.lastNeed) return r + '\ufffd';
  return r;
}

// UTF-16LE typically needs two bytes per character, but even if we have an even
// number of bytes available, we need to check if we end on a leading/high
// surrogate. In that case, we need to wait for the next two bytes in order to
// decode the last character properly.
function utf16Text(buf, i) {
  if ((buf.length - i) % 2 === 0) {
    var r = buf.toString('utf16le', i);
    if (r) {
      var c = r.charCodeAt(r.length - 1);
      if (c >= 0xD800 && c <= 0xDBFF) {
        this.lastNeed = 2;
        this.lastTotal = 4;
        this.lastChar[0] = buf[buf.length - 2];
        this.lastChar[1] = buf[buf.length - 1];
        return r.slice(0, -1);
      }
    }
    return r;
  }
  this.lastNeed = 1;
  this.lastTotal = 2;
  this.lastChar[0] = buf[buf.length - 1];
  return buf.toString('utf16le', i, buf.length - 1);
}

// For UTF-16LE we do not explicitly append special replacement characters if we
// end on a partial character, we simply let v8 handle that.
function utf16End(buf) {
  var r = buf && buf.length ? this.write(buf) : '';
  if (this.lastNeed) {
    var end = this.lastTotal - this.lastNeed;
    return r + this.lastChar.toString('utf16le', 0, end);
  }
  return r;
}

function base64Text(buf, i) {
  var n = (buf.length - i) % 3;
  if (n === 0) return buf.toString('base64', i);
  this.lastNeed = 3 - n;
  this.lastTotal = 3;
  if (n === 1) {
    this.lastChar[0] = buf[buf.length - 1];
  } else {
    this.lastChar[0] = buf[buf.length - 2];
    this.lastChar[1] = buf[buf.length - 1];
  }
  return buf.toString('base64', i, buf.length - n);
}

function base64End(buf) {
  var r = buf && buf.length ? this.write(buf) : '';
  if (this.lastNeed) return r + this.lastChar.toString('base64', 0, 3 - this.lastNeed);
  return r;
}

// Pass bytes on through for single-byte encodings (e.g. ascii, latin1, hex)
function simpleWrite(buf) {
  return buf.toString(this.encoding);
}

function simpleEnd(buf) {
  return buf && buf.length ? this.write(buf) : '';
}
},{"safe-buffer":79}],85:[function(require,module,exports){
(function (setImmediate,clearImmediate){
var nextTick = require('process/browser.js').nextTick;
var apply = Function.prototype.apply;
var slice = Array.prototype.slice;
var immediateIds = {};
var nextImmediateId = 0;

// DOM APIs, for completeness

exports.setTimeout = function() {
  return new Timeout(apply.call(setTimeout, window, arguments), clearTimeout);
};
exports.setInterval = function() {
  return new Timeout(apply.call(setInterval, window, arguments), clearInterval);
};
exports.clearTimeout =
exports.clearInterval = function(timeout) { timeout.close(); };

function Timeout(id, clearFn) {
  this._id = id;
  this._clearFn = clearFn;
}
Timeout.prototype.unref = Timeout.prototype.ref = function() {};
Timeout.prototype.close = function() {
  this._clearFn.call(window, this._id);
};

// Does not start the time, just sets up the members needed.
exports.enroll = function(item, msecs) {
  clearTimeout(item._idleTimeoutId);
  item._idleTimeout = msecs;
};

exports.unenroll = function(item) {
  clearTimeout(item._idleTimeoutId);
  item._idleTimeout = -1;
};

exports._unrefActive = exports.active = function(item) {
  clearTimeout(item._idleTimeoutId);

  var msecs = item._idleTimeout;
  if (msecs >= 0) {
    item._idleTimeoutId = setTimeout(function onTimeout() {
      if (item._onTimeout)
        item._onTimeout();
    }, msecs);
  }
};

// That's not how node.js implements it but the exposed api is the same.
exports.setImmediate = typeof setImmediate === "function" ? setImmediate : function(fn) {
  var id = nextImmediateId++;
  var args = arguments.length < 2 ? false : slice.call(arguments, 1);

  immediateIds[id] = true;

  nextTick(function onNextTick() {
    if (immediateIds[id]) {
      // fn.call() is faster so we optimize for the common use-case
      // @see http://jsperf.com/call-apply-segu
      if (args) {
        fn.apply(null, args);
      } else {
        fn.call(null);
      }
      // Prevent ids from leaking
      exports.clearImmediate(id);
    }
  });

  return id;
};

exports.clearImmediate = typeof clearImmediate === "function" ? clearImmediate : function(id) {
  delete immediateIds[id];
};
}).call(this,require("timers").setImmediate,require("timers").clearImmediate)

},{"process/browser.js":66,"timers":85}],86:[function(require,module,exports){
var Buffer = require('buffer').Buffer

module.exports = function (buf) {
	// If the buffer is backed by a Uint8Array, a faster version will work
	if (buf instanceof Uint8Array) {
		// If the buffer isn't a subarray, return the underlying ArrayBuffer
		if (buf.byteOffset === 0 && buf.byteLength === buf.buffer.byteLength) {
			return buf.buffer
		} else if (typeof buf.buffer.slice === 'function') {
			// Otherwise we need to get a proper copy
			return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength)
		}
	}

	if (Buffer.isBuffer(buf)) {
		// This is the slow version that will work with any Buffer
		// implementation (even in old browsers)
		var arrayCopy = new Uint8Array(buf.length)
		var len = buf.length
		for (var i = 0; i < len; i++) {
			arrayCopy[i] = buf[i]
		}
		return arrayCopy.buffer
	} else {
		throw new Error('Argument must be a Buffer')
	}
}

},{"buffer":23}],87:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

'use strict';

var punycode = require('punycode');
var util = require('./util');

exports.parse = urlParse;
exports.resolve = urlResolve;
exports.resolveObject = urlResolveObject;
exports.format = urlFormat;

exports.Url = Url;

function Url() {
  this.protocol = null;
  this.slashes = null;
  this.auth = null;
  this.host = null;
  this.port = null;
  this.hostname = null;
  this.hash = null;
  this.search = null;
  this.query = null;
  this.pathname = null;
  this.path = null;
  this.href = null;
}

// Reference: RFC 3986, RFC 1808, RFC 2396

// define these here so at least they only have to be
// compiled once on the first module load.
var protocolPattern = /^([a-z0-9.+-]+:)/i,
    portPattern = /:[0-9]*$/,

    // Special case for a simple path URL
    simplePathPattern = /^(\/\/?(?!\/)[^\?\s]*)(\?[^\s]*)?$/,

    // RFC 2396: characters reserved for delimiting URLs.
    // We actually just auto-escape these.
    delims = ['<', '>', '"', '`', ' ', '\r', '\n', '\t'],

    // RFC 2396: characters not allowed for various reasons.
    unwise = ['{', '}', '|', '\\', '^', '`'].concat(delims),

    // Allowed by RFCs, but cause of XSS attacks.  Always escape these.
    autoEscape = ['\''].concat(unwise),
    // Characters that are never ever allowed in a hostname.
    // Note that any invalid chars are also handled, but these
    // are the ones that are *expected* to be seen, so we fast-path
    // them.
    nonHostChars = ['%', '/', '?', ';', '#'].concat(autoEscape),
    hostEndingChars = ['/', '?', '#'],
    hostnameMaxLen = 255,
    hostnamePartPattern = /^[+a-z0-9A-Z_-]{0,63}$/,
    hostnamePartStart = /^([+a-z0-9A-Z_-]{0,63})(.*)$/,
    // protocols that can allow "unsafe" and "unwise" chars.
    unsafeProtocol = {
      'javascript': true,
      'javascript:': true
    },
    // protocols that never have a hostname.
    hostlessProtocol = {
      'javascript': true,
      'javascript:': true
    },
    // protocols that always contain a // bit.
    slashedProtocol = {
      'http': true,
      'https': true,
      'ftp': true,
      'gopher': true,
      'file': true,
      'http:': true,
      'https:': true,
      'ftp:': true,
      'gopher:': true,
      'file:': true
    },
    querystring = require('querystring');

function urlParse(url, parseQueryString, slashesDenoteHost) {
  if (url && util.isObject(url) && url instanceof Url) return url;

  var u = new Url;
  u.parse(url, parseQueryString, slashesDenoteHost);
  return u;
}

Url.prototype.parse = function(url, parseQueryString, slashesDenoteHost) {
  if (!util.isString(url)) {
    throw new TypeError("Parameter 'url' must be a string, not " + typeof url);
  }

  // Copy chrome, IE, opera backslash-handling behavior.
  // Back slashes before the query string get converted to forward slashes
  // See: https://code.google.com/p/chromium/issues/detail?id=25916
  var queryIndex = url.indexOf('?'),
      splitter =
          (queryIndex !== -1 && queryIndex < url.indexOf('#')) ? '?' : '#',
      uSplit = url.split(splitter),
      slashRegex = /\\/g;
  uSplit[0] = uSplit[0].replace(slashRegex, '/');
  url = uSplit.join(splitter);

  var rest = url;

  // trim before proceeding.
  // This is to support parse stuff like "  http://foo.com  \n"
  rest = rest.trim();

  if (!slashesDenoteHost && url.split('#').length === 1) {
    // Try fast path regexp
    var simplePath = simplePathPattern.exec(rest);
    if (simplePath) {
      this.path = rest;
      this.href = rest;
      this.pathname = simplePath[1];
      if (simplePath[2]) {
        this.search = simplePath[2];
        if (parseQueryString) {
          this.query = querystring.parse(this.search.substr(1));
        } else {
          this.query = this.search.substr(1);
        }
      } else if (parseQueryString) {
        this.search = '';
        this.query = {};
      }
      return this;
    }
  }

  var proto = protocolPattern.exec(rest);
  if (proto) {
    proto = proto[0];
    var lowerProto = proto.toLowerCase();
    this.protocol = lowerProto;
    rest = rest.substr(proto.length);
  }

  // figure out if it's got a host
  // user@server is *always* interpreted as a hostname, and url
  // resolution will treat //foo/bar as host=foo,path=bar because that's
  // how the browser resolves relative URLs.
  if (slashesDenoteHost || proto || rest.match(/^\/\/[^@\/]+@[^@\/]+/)) {
    var slashes = rest.substr(0, 2) === '//';
    if (slashes && !(proto && hostlessProtocol[proto])) {
      rest = rest.substr(2);
      this.slashes = true;
    }
  }

  if (!hostlessProtocol[proto] &&
      (slashes || (proto && !slashedProtocol[proto]))) {

    // there's a hostname.
    // the first instance of /, ?, ;, or # ends the host.
    //
    // If there is an @ in the hostname, then non-host chars *are* allowed
    // to the left of the last @ sign, unless some host-ending character
    // comes *before* the @-sign.
    // URLs are obnoxious.
    //
    // ex:
    // http://a@b@c/ => user:a@b host:c
    // http://a@b?@c => user:a host:c path:/?@c

    // v0.12 TODO(isaacs): This is not quite how Chrome does things.
    // Review our test case against browsers more comprehensively.

    // find the first instance of any hostEndingChars
    var hostEnd = -1;
    for (var i = 0; i < hostEndingChars.length; i++) {
      var hec = rest.indexOf(hostEndingChars[i]);
      if (hec !== -1 && (hostEnd === -1 || hec < hostEnd))
        hostEnd = hec;
    }

    // at this point, either we have an explicit point where the
    // auth portion cannot go past, or the last @ char is the decider.
    var auth, atSign;
    if (hostEnd === -1) {
      // atSign can be anywhere.
      atSign = rest.lastIndexOf('@');
    } else {
      // atSign must be in auth portion.
      // http://a@b/c@d => host:b auth:a path:/c@d
      atSign = rest.lastIndexOf('@', hostEnd);
    }

    // Now we have a portion which is definitely the auth.
    // Pull that off.
    if (atSign !== -1) {
      auth = rest.slice(0, atSign);
      rest = rest.slice(atSign + 1);
      this.auth = decodeURIComponent(auth);
    }

    // the host is the remaining to the left of the first non-host char
    hostEnd = -1;
    for (var i = 0; i < nonHostChars.length; i++) {
      var hec = rest.indexOf(nonHostChars[i]);
      if (hec !== -1 && (hostEnd === -1 || hec < hostEnd))
        hostEnd = hec;
    }
    // if we still have not hit it, then the entire thing is a host.
    if (hostEnd === -1)
      hostEnd = rest.length;

    this.host = rest.slice(0, hostEnd);
    rest = rest.slice(hostEnd);

    // pull out port.
    this.parseHost();

    // we've indicated that there is a hostname,
    // so even if it's empty, it has to be present.
    this.hostname = this.hostname || '';

    // if hostname begins with [ and ends with ]
    // assume that it's an IPv6 address.
    var ipv6Hostname = this.hostname[0] === '[' &&
        this.hostname[this.hostname.length - 1] === ']';

    // validate a little.
    if (!ipv6Hostname) {
      var hostparts = this.hostname.split(/\./);
      for (var i = 0, l = hostparts.length; i < l; i++) {
        var part = hostparts[i];
        if (!part) continue;
        if (!part.match(hostnamePartPattern)) {
          var newpart = '';
          for (var j = 0, k = part.length; j < k; j++) {
            if (part.charCodeAt(j) > 127) {
              // we replace non-ASCII char with a temporary placeholder
              // we need this to make sure size of hostname is not
              // broken by replacing non-ASCII by nothing
              newpart += 'x';
            } else {
              newpart += part[j];
            }
          }
          // we test again with ASCII char only
          if (!newpart.match(hostnamePartPattern)) {
            var validParts = hostparts.slice(0, i);
            var notHost = hostparts.slice(i + 1);
            var bit = part.match(hostnamePartStart);
            if (bit) {
              validParts.push(bit[1]);
              notHost.unshift(bit[2]);
            }
            if (notHost.length) {
              rest = '/' + notHost.join('.') + rest;
            }
            this.hostname = validParts.join('.');
            break;
          }
        }
      }
    }

    if (this.hostname.length > hostnameMaxLen) {
      this.hostname = '';
    } else {
      // hostnames are always lower case.
      this.hostname = this.hostname.toLowerCase();
    }

    if (!ipv6Hostname) {
      // IDNA Support: Returns a punycoded representation of "domain".
      // It only converts parts of the domain name that
      // have non-ASCII characters, i.e. it doesn't matter if
      // you call it with a domain that already is ASCII-only.
      this.hostname = punycode.toASCII(this.hostname);
    }

    var p = this.port ? ':' + this.port : '';
    var h = this.hostname || '';
    this.host = h + p;
    this.href += this.host;

    // strip [ and ] from the hostname
    // the host field still retains them, though
    if (ipv6Hostname) {
      this.hostname = this.hostname.substr(1, this.hostname.length - 2);
      if (rest[0] !== '/') {
        rest = '/' + rest;
      }
    }
  }

  // now rest is set to the post-host stuff.
  // chop off any delim chars.
  if (!unsafeProtocol[lowerProto]) {

    // First, make 100% sure that any "autoEscape" chars get
    // escaped, even if encodeURIComponent doesn't think they
    // need to be.
    for (var i = 0, l = autoEscape.length; i < l; i++) {
      var ae = autoEscape[i];
      if (rest.indexOf(ae) === -1)
        continue;
      var esc = encodeURIComponent(ae);
      if (esc === ae) {
        esc = escape(ae);
      }
      rest = rest.split(ae).join(esc);
    }
  }


  // chop off from the tail first.
  var hash = rest.indexOf('#');
  if (hash !== -1) {
    // got a fragment string.
    this.hash = rest.substr(hash);
    rest = rest.slice(0, hash);
  }
  var qm = rest.indexOf('?');
  if (qm !== -1) {
    this.search = rest.substr(qm);
    this.query = rest.substr(qm + 1);
    if (parseQueryString) {
      this.query = querystring.parse(this.query);
    }
    rest = rest.slice(0, qm);
  } else if (parseQueryString) {
    // no query string, but parseQueryString still requested
    this.search = '';
    this.query = {};
  }
  if (rest) this.pathname = rest;
  if (slashedProtocol[lowerProto] &&
      this.hostname && !this.pathname) {
    this.pathname = '/';
  }

  //to support http.request
  if (this.pathname || this.search) {
    var p = this.pathname || '';
    var s = this.search || '';
    this.path = p + s;
  }

  // finally, reconstruct the href based on what has been validated.
  this.href = this.format();
  return this;
};

// format a parsed object into a url string
function urlFormat(obj) {
  // ensure it's an object, and not a string url.
  // If it's an obj, this is a no-op.
  // this way, you can call url_format() on strings
  // to clean up potentially wonky urls.
  if (util.isString(obj)) obj = urlParse(obj);
  if (!(obj instanceof Url)) return Url.prototype.format.call(obj);
  return obj.format();
}

Url.prototype.format = function() {
  var auth = this.auth || '';
  if (auth) {
    auth = encodeURIComponent(auth);
    auth = auth.replace(/%3A/i, ':');
    auth += '@';
  }

  var protocol = this.protocol || '',
      pathname = this.pathname || '',
      hash = this.hash || '',
      host = false,
      query = '';

  if (this.host) {
    host = auth + this.host;
  } else if (this.hostname) {
    host = auth + (this.hostname.indexOf(':') === -1 ?
        this.hostname :
        '[' + this.hostname + ']');
    if (this.port) {
      host += ':' + this.port;
    }
  }

  if (this.query &&
      util.isObject(this.query) &&
      Object.keys(this.query).length) {
    query = querystring.stringify(this.query);
  }

  var search = this.search || (query && ('?' + query)) || '';

  if (protocol && protocol.substr(-1) !== ':') protocol += ':';

  // only the slashedProtocols get the //.  Not mailto:, xmpp:, etc.
  // unless they had them to begin with.
  if (this.slashes ||
      (!protocol || slashedProtocol[protocol]) && host !== false) {
    host = '//' + (host || '');
    if (pathname && pathname.charAt(0) !== '/') pathname = '/' + pathname;
  } else if (!host) {
    host = '';
  }

  if (hash && hash.charAt(0) !== '#') hash = '#' + hash;
  if (search && search.charAt(0) !== '?') search = '?' + search;

  pathname = pathname.replace(/[?#]/g, function(match) {
    return encodeURIComponent(match);
  });
  search = search.replace('#', '%23');

  return protocol + host + pathname + search + hash;
};

function urlResolve(source, relative) {
  return urlParse(source, false, true).resolve(relative);
}

Url.prototype.resolve = function(relative) {
  return this.resolveObject(urlParse(relative, false, true)).format();
};

function urlResolveObject(source, relative) {
  if (!source) return relative;
  return urlParse(source, false, true).resolveObject(relative);
}

Url.prototype.resolveObject = function(relative) {
  if (util.isString(relative)) {
    var rel = new Url();
    rel.parse(relative, false, true);
    relative = rel;
  }

  var result = new Url();
  var tkeys = Object.keys(this);
  for (var tk = 0; tk < tkeys.length; tk++) {
    var tkey = tkeys[tk];
    result[tkey] = this[tkey];
  }

  // hash is always overridden, no matter what.
  // even href="" will remove it.
  result.hash = relative.hash;

  // if the relative url is empty, then there's nothing left to do here.
  if (relative.href === '') {
    result.href = result.format();
    return result;
  }

  // hrefs like //foo/bar always cut to the protocol.
  if (relative.slashes && !relative.protocol) {
    // take everything except the protocol from relative
    var rkeys = Object.keys(relative);
    for (var rk = 0; rk < rkeys.length; rk++) {
      var rkey = rkeys[rk];
      if (rkey !== 'protocol')
        result[rkey] = relative[rkey];
    }

    //urlParse appends trailing / to urls like http://www.example.com
    if (slashedProtocol[result.protocol] &&
        result.hostname && !result.pathname) {
      result.path = result.pathname = '/';
    }

    result.href = result.format();
    return result;
  }

  if (relative.protocol && relative.protocol !== result.protocol) {
    // if it's a known url protocol, then changing
    // the protocol does weird things
    // first, if it's not file:, then we MUST have a host,
    // and if there was a path
    // to begin with, then we MUST have a path.
    // if it is file:, then the host is dropped,
    // because that's known to be hostless.
    // anything else is assumed to be absolute.
    if (!slashedProtocol[relative.protocol]) {
      var keys = Object.keys(relative);
      for (var v = 0; v < keys.length; v++) {
        var k = keys[v];
        result[k] = relative[k];
      }
      result.href = result.format();
      return result;
    }

    result.protocol = relative.protocol;
    if (!relative.host && !hostlessProtocol[relative.protocol]) {
      var relPath = (relative.pathname || '').split('/');
      while (relPath.length && !(relative.host = relPath.shift()));
      if (!relative.host) relative.host = '';
      if (!relative.hostname) relative.hostname = '';
      if (relPath[0] !== '') relPath.unshift('');
      if (relPath.length < 2) relPath.unshift('');
      result.pathname = relPath.join('/');
    } else {
      result.pathname = relative.pathname;
    }
    result.search = relative.search;
    result.query = relative.query;
    result.host = relative.host || '';
    result.auth = relative.auth;
    result.hostname = relative.hostname || relative.host;
    result.port = relative.port;
    // to support http.request
    if (result.pathname || result.search) {
      var p = result.pathname || '';
      var s = result.search || '';
      result.path = p + s;
    }
    result.slashes = result.slashes || relative.slashes;
    result.href = result.format();
    return result;
  }

  var isSourceAbs = (result.pathname && result.pathname.charAt(0) === '/'),
      isRelAbs = (
          relative.host ||
          relative.pathname && relative.pathname.charAt(0) === '/'
      ),
      mustEndAbs = (isRelAbs || isSourceAbs ||
                    (result.host && relative.pathname)),
      removeAllDots = mustEndAbs,
      srcPath = result.pathname && result.pathname.split('/') || [],
      relPath = relative.pathname && relative.pathname.split('/') || [],
      psychotic = result.protocol && !slashedProtocol[result.protocol];

  // if the url is a non-slashed url, then relative
  // links like ../.. should be able
  // to crawl up to the hostname, as well.  This is strange.
  // result.protocol has already been set by now.
  // Later on, put the first path part into the host field.
  if (psychotic) {
    result.hostname = '';
    result.port = null;
    if (result.host) {
      if (srcPath[0] === '') srcPath[0] = result.host;
      else srcPath.unshift(result.host);
    }
    result.host = '';
    if (relative.protocol) {
      relative.hostname = null;
      relative.port = null;
      if (relative.host) {
        if (relPath[0] === '') relPath[0] = relative.host;
        else relPath.unshift(relative.host);
      }
      relative.host = null;
    }
    mustEndAbs = mustEndAbs && (relPath[0] === '' || srcPath[0] === '');
  }

  if (isRelAbs) {
    // it's absolute.
    result.host = (relative.host || relative.host === '') ?
                  relative.host : result.host;
    result.hostname = (relative.hostname || relative.hostname === '') ?
                      relative.hostname : result.hostname;
    result.search = relative.search;
    result.query = relative.query;
    srcPath = relPath;
    // fall through to the dot-handling below.
  } else if (relPath.length) {
    // it's relative
    // throw away the existing file, and take the new path instead.
    if (!srcPath) srcPath = [];
    srcPath.pop();
    srcPath = srcPath.concat(relPath);
    result.search = relative.search;
    result.query = relative.query;
  } else if (!util.isNullOrUndefined(relative.search)) {
    // just pull out the search.
    // like href='?foo'.
    // Put this after the other two cases because it simplifies the booleans
    if (psychotic) {
      result.hostname = result.host = srcPath.shift();
      //occationaly the auth can get stuck only in host
      //this especially happens in cases like
      //url.resolveObject('mailto:local1@domain1', 'local2@domain2')
      var authInHost = result.host && result.host.indexOf('@') > 0 ?
                       result.host.split('@') : false;
      if (authInHost) {
        result.auth = authInHost.shift();
        result.host = result.hostname = authInHost.shift();
      }
    }
    result.search = relative.search;
    result.query = relative.query;
    //to support http.request
    if (!util.isNull(result.pathname) || !util.isNull(result.search)) {
      result.path = (result.pathname ? result.pathname : '') +
                    (result.search ? result.search : '');
    }
    result.href = result.format();
    return result;
  }

  if (!srcPath.length) {
    // no path at all.  easy.
    // we've already handled the other stuff above.
    result.pathname = null;
    //to support http.request
    if (result.search) {
      result.path = '/' + result.search;
    } else {
      result.path = null;
    }
    result.href = result.format();
    return result;
  }

  // if a url ENDs in . or .., then it must get a trailing slash.
  // however, if it ends in anything else non-slashy,
  // then it must NOT get a trailing slash.
  var last = srcPath.slice(-1)[0];
  var hasTrailingSlash = (
      (result.host || relative.host || srcPath.length > 1) &&
      (last === '.' || last === '..') || last === '');

  // strip single dots, resolve double dots to parent dir
  // if the path tries to go above the root, `up` ends up > 0
  var up = 0;
  for (var i = srcPath.length; i >= 0; i--) {
    last = srcPath[i];
    if (last === '.') {
      srcPath.splice(i, 1);
    } else if (last === '..') {
      srcPath.splice(i, 1);
      up++;
    } else if (up) {
      srcPath.splice(i, 1);
      up--;
    }
  }

  // if the path is allowed to go above the root, restore leading ..s
  if (!mustEndAbs && !removeAllDots) {
    for (; up--; up) {
      srcPath.unshift('..');
    }
  }

  if (mustEndAbs && srcPath[0] !== '' &&
      (!srcPath[0] || srcPath[0].charAt(0) !== '/')) {
    srcPath.unshift('');
  }

  if (hasTrailingSlash && (srcPath.join('/').substr(-1) !== '/')) {
    srcPath.push('');
  }

  var isAbsolute = srcPath[0] === '' ||
      (srcPath[0] && srcPath[0].charAt(0) === '/');

  // put the host back
  if (psychotic) {
    result.hostname = result.host = isAbsolute ? '' :
                                    srcPath.length ? srcPath.shift() : '';
    //occationaly the auth can get stuck only in host
    //this especially happens in cases like
    //url.resolveObject('mailto:local1@domain1', 'local2@domain2')
    var authInHost = result.host && result.host.indexOf('@') > 0 ?
                     result.host.split('@') : false;
    if (authInHost) {
      result.auth = authInHost.shift();
      result.host = result.hostname = authInHost.shift();
    }
  }

  mustEndAbs = mustEndAbs || (result.host && srcPath.length);

  if (mustEndAbs && !isAbsolute) {
    srcPath.unshift('');
  }

  if (!srcPath.length) {
    result.pathname = null;
    result.path = null;
  } else {
    result.pathname = srcPath.join('/');
  }

  //to support request.http
  if (!util.isNull(result.pathname) || !util.isNull(result.search)) {
    result.path = (result.pathname ? result.pathname : '') +
                  (result.search ? result.search : '');
  }
  result.auth = relative.auth || result.auth;
  result.slashes = result.slashes || relative.slashes;
  result.href = result.format();
  return result;
};

Url.prototype.parseHost = function() {
  var host = this.host;
  var port = portPattern.exec(host);
  if (port) {
    port = port[0];
    if (port !== ':') {
      this.port = port.substr(1);
    }
    host = host.substr(0, host.length - port.length);
  }
  if (host) this.hostname = host;
};

},{"./util":88,"punycode":22,"querystring":69}],88:[function(require,module,exports){
'use strict';

module.exports = {
  isString: function(arg) {
    return typeof(arg) === 'string';
  },
  isObject: function(arg) {
    return typeof(arg) === 'object' && arg !== null;
  },
  isNull: function(arg) {
    return arg === null;
  },
  isNullOrUndefined: function(arg) {
    return arg == null;
  }
};

},{}],89:[function(require,module,exports){
(function (global){

/**
 * Module exports.
 */

module.exports = deprecate;

/**
 * Mark that a method should not be used.
 * Returns a modified function which warns once by default.
 *
 * If `localStorage.noDeprecation = true` is set, then it is a no-op.
 *
 * If `localStorage.throwDeprecation = true` is set, then deprecated functions
 * will throw an Error when invoked.
 *
 * If `localStorage.traceDeprecation = true` is set, then deprecated functions
 * will invoke `console.trace()` instead of `console.error()`.
 *
 * @param {Function} fn - the function to deprecate
 * @param {String} msg - the string to print to the console when `fn` is invoked
 * @returns {Function} a new "deprecated" version of `fn`
 * @api public
 */

function deprecate (fn, msg) {
  if (config('noDeprecation')) {
    return fn;
  }

  var warned = false;
  function deprecated() {
    if (!warned) {
      if (config('throwDeprecation')) {
        throw new Error(msg);
      } else if (config('traceDeprecation')) {
        console.trace(msg);
      } else {
        console.warn(msg);
      }
      warned = true;
    }
    return fn.apply(this, arguments);
  }

  return deprecated;
}

/**
 * Checks `localStorage` for boolean values for the given `name`.
 *
 * @param {String} name
 * @returns {Boolean}
 * @api private
 */

function config (name) {
  // accessing global.localStorage can trigger a DOMException in sandboxed iframes
  try {
    if (!global.localStorage) return false;
  } catch (_) {
    return false;
  }
  var val = global.localStorage[name];
  if (null == val) return false;
  return String(val).toLowerCase() === 'true';
}

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{}],90:[function(require,module,exports){
module.exports = extend

var hasOwnProperty = Object.prototype.hasOwnProperty;

function extend() {
    var target = {}

    for (var i = 0; i < arguments.length; i++) {
        var source = arguments[i]

        for (var key in source) {
            if (hasOwnProperty.call(source, key)) {
                target[key] = source[key]
            }
        }
    }

    return target
}

},{}]},{},[3])(3)
});
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