Add YAML module

.gitignore

@@ -4,4 +4,5 @@ deno.d.ts
 node_modules
 package.json
 package-lock.json
+yarn.lock
 .vscode

encoding/README.md

@@ -217,3 +217,24 @@ const obj = {
 };
 const tomlString = stringify(obj);
 ```
+
+## YAML
+
+YAML parser / dumper for Deno
+
+Heavily inspired from [js-yaml]
+
+### Example
+
+See [`./yaml/example`](./yaml/example) folder and [js-yaml] repository.
+
+### :warning: Limitations
+
+- `binary` type is currently not stable
+- `function`, `regexp`, and `undefined` type are currently not supported
+
+# Basic usage
+
+TBD
+
+[js-yaml]: https://github.com/nodeca/js-yaml

encoding/test.ts

@@ -2,3 +2,4 @@
 import "./hex_test.ts";
 import "./toml_test.ts";
 import "./csv_test.ts";
+import "./yaml_test.ts";

encoding/yaml.ts

@@ -0,0 +1,8 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+export * from "./yaml/parse.ts";
+export * from "./yaml/stringify.ts";
+export * from "./yaml/schema/mod.ts";

encoding/yaml/Mark.ts

@@ -0,0 +1,76 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { repeat } from "./utils.ts";
+
+export class Mark {
+  constructor(
+    public name: string,
+    public buffer: string,
+    public position: number,
+    public line: number,
+    public column: number
+  ) {}
+
+  public getSnippet(indent = 4, maxLength = 75): string | null {
+    if (!this.buffer) return null;
+
+    let head = "";
+    let 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;
+      }
+    }
+
+    let tail = "";
+    let 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;
+      }
+    }
+
+    const snippet = this.buffer.slice(start, end);
+    return `${repeat(" ", indent)}${head}${snippet}${tail}\n${repeat(
+      " ",
+      indent + this.position - start + head.length
+    )}^`;
+  }
+
+  public toString(compact?: boolean): string {
+    let snippet,
+      where = "";
+
+    if (this.name) {
+      where += `in "${this.name}" `;
+    }
+
+    where += `at line ${this.line + 1}, column ${this.column + 1}`;
+
+    if (!compact) {
+      snippet = this.getSnippet();
+
+      if (snippet) {
+        where += `:\n${snippet}`;
+      }
+    }
+
+    return where;
+  }
+}

encoding/yaml/Schema.ts

@@ -0,0 +1,101 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { YAMLError } from "./error.ts";
+import { KindType, Type } from "./type.ts";
+import { ArrayObject, Any } from "./utils.ts";
+
+function compileList(
+  schema: Schema,
+  name: "implicit" | "explicit",
+  result: Type[]
+): Type[] {
+  const exclude: number[] = [];
+
+  for (const includedSchema of schema.include) {
+    result = compileList(includedSchema, name, result);
+  }
+
+  for (const currentType of schema[name]) {
+    for (
+      let previousIndex = 0;
+      previousIndex < result.length;
+      previousIndex++
+    ) {
+      const previousType = result[previousIndex];
+      if (
+        previousType.tag === currentType.tag &&
+        previousType.kind === currentType.kind
+      ) {
+        exclude.push(previousIndex);
+      }
+    }
+
+    result.push(currentType);
+  }
+
+  return result.filter((type, index): unknown => !exclude.includes(index));
+}
+
+export type TypeMap = { [k in KindType | "fallback"]: ArrayObject<Type> };
+function compileMap(...typesList: Type[][]): TypeMap {
+  const result: TypeMap = {
+    fallback: {},
+    mapping: {},
+    scalar: {},
+    sequence: {}
+  };
+
+  for (const types of typesList) {
+    for (const type of types) {
+      if (type.kind !== null) {
+        result[type.kind][type.tag] = result["fallback"][type.tag] = type;
+      }
+    }
+  }
+  return result;
+}
+
+export class Schema implements SchemaDefinition {
+  public static SCHEMA_DEFAULT?: Schema;
+
+  public implicit: Type[];
+  public explicit: Type[];
+  public include: Schema[];
+
+  public compiledImplicit: Type[];
+  public compiledExplicit: Type[];
+  public compiledTypeMap: TypeMap;
+
+  constructor(definition: SchemaDefinition) {
+    this.explicit = definition.explicit || [];
+    this.implicit = definition.implicit || [];
+    this.include = definition.include || [];
+
+    for (const type of this.implicit) {
+      if (type.loadKind && type.loadKind !== "scalar") {
+        throw new YAMLError(
+          // eslint-disable-next-line max-len
+          "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
+    );
+  }
+
+  public static create(): void {}
+}
+
+export interface SchemaDefinition {
+  implicit?: Any[];
+  explicit?: Type[];
+  include?: Schema[];
+}

encoding/yaml/State.ts

@@ -0,0 +1,11 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { SchemaDefinition } from "./schema.ts";
+import { DEFAULT_SCHEMA } from "./schema/mod.ts";
+
+export abstract class State {
+  constructor(public schema: SchemaDefinition = DEFAULT_SCHEMA) {}
+}

encoding/yaml/Type.ts

@@ -0,0 +1,55 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { ArrayObject, Any } from "./utils.ts";
+
+export type KindType = "sequence" | "scalar" | "mapping";
+export type StyleVariant = "lowercase" | "uppercase" | "camelcase" | "decimal";
+export type RepresentFn = (data: Any, style?: StyleVariant) => Any;
+
+const DEFAULT_RESOLVE = (): boolean => true;
+const DEFAULT_CONSTRUCT = (data: Any): Any => data;
+
+interface TypeOptions {
+  kind: KindType;
+  resolve?: (data: Any) => boolean;
+  construct?: (data: string) => Any;
+  instanceOf?: Any;
+  predicate?: (data: object) => boolean;
+  represent?: RepresentFn | ArrayObject<RepresentFn>;
+  defaultStyle?: StyleVariant;
+  styleAliases?: ArrayObject;
+}
+
+function checkTagFormat(tag: string): string {
+  return tag;
+}
+
+export class Type {
+  public tag: string;
+  public kind: KindType | null = null;
+  public instanceOf: Any;
+  public predicate?: (data: object) => boolean;
+  public represent?: RepresentFn | ArrayObject<RepresentFn>;
+  public defaultStyle?: StyleVariant;
+  public styleAliases?: ArrayObject;
+  public loadKind?: KindType;
+
+  constructor(tag: string, options?: TypeOptions) {
+    this.tag = checkTagFormat(tag);
+    if (options) {
+      this.kind = options.kind;
+      this.resolve = options.resolve || DEFAULT_RESOLVE;
+      this.construct = options.construct || DEFAULT_CONSTRUCT;
+      this.instanceOf = options.instanceOf;
+      this.predicate = options.predicate;
+      this.represent = options.represent;
+      this.defaultStyle = options.defaultStyle;
+      this.styleAliases = options.styleAliases;
+    }
+  }
+  public resolve: (data?: Any) => boolean = (): boolean => true;
+  public construct: (data?: Any) => Any = (data): Any => data;
+}

encoding/yaml/__test__/00-units.js

@@ -0,0 +1,17 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+var path = require('path');
+var fs   = require('fs');
+
+
+suite('Units', function () {
+  var directory = path.resolve(__dirname, 'units');
+
+  fs.readdirSync(directory).forEach(function (file) {
+    if (path.extname(file) === '.js') {
+      require(path.resolve(directory, file));
+    }
+  });
+});

encoding/yaml/__test__/10-loader.js

@@ -0,0 +1,39 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+var assert = require('assert');
+var path   = require('path');
+var fs     = require('fs');
+var yaml   = require('../');
+
+var TEST_SCHEMA = require('./support/schema').TEST_SCHEMA;
+
+
+suite('Loader', function () {
+  var samplesDir = path.resolve(__dirname, 'samples-common');
+
+  fs.readdirSync(samplesDir).forEach(function (jsFile) {
+    if (path.extname(jsFile) !== '.js') return; // continue
+
+    var yamlFile = path.resolve(samplesDir, path.basename(jsFile, '.js') + '.yml');
+
+    test(path.basename(jsFile, '.js'), function () {
+      var expected = require(path.resolve(samplesDir, jsFile));
+      var actual   = [];
+
+      yaml.loadAll(fs.readFileSync(yamlFile, { encoding: 'utf8' }), function (doc) { actual.push(doc); }, {
+        filename: yamlFile,
+        schema: TEST_SCHEMA
+      });
+
+      if (actual.length === 1) actual = actual[0];
+
+      if (typeof expected === 'function') {
+        expected.call(this, actual);
+      } else {
+        assert.deepEqual(actual, expected);
+      }
+    });
+  });
+});

encoding/yaml/__test__/11-load-errors.js

@@ -0,0 +1,35 @@
+// Ported from js-yaml v3.13.1:
+// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+var assert = require('assert');
+var path   = require('path');
+var fs     = require('fs');
+var yaml   = require('../');
+
+var TEST_SCHEMA = require('./support/schema').TEST_SCHEMA;
+
+
+suite('Load errors', function () {
+  var samplesDir = path.resolve(__dirname, 'samples-load-errors');
+
+  fs.readdirSync(samplesDir).forEach(function (sampleName) {
+    var yamlFile = path.resolve(samplesDir, sampleName);
+
+    test(path.basename(sampleName, '.yml'), function () {
+      var yamlSource = fs.readFileSync(yamlFile, { encoding: 'utf8' });
+
+      assert.throws(function () {
+        yaml.loadAll(
+          yamlSource,
+          function () {},
+          {
+            filename: yamlFile,
+            schema: TEST_SCHEMA,
+            onWarning: function (e) { throw e; }
+          }
+        );
+      }, yaml.YAMLException, yamlFile);
+    });
+  });
+});