diff --git a/polyfill/intersectionobserver-polyfill.js b/polyfill/intersectionobserver-polyfill.js
new file mode 100644
index 0000000..e99ec37
--- /dev/null
+++ b/polyfill/intersectionobserver-polyfill.js
@@ -0,0 +1,250 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+// TODO: rootMargin are completely ignored for now
+(function(scope) {
+ if('IntersectionObserver' in window) {
+ return;
+ }
+
+ var POLL_INTERVAL = 100;
+
+ // Constructor
+ var IntersectionObserver = function(callback, options) {
+ options = options || {};
+
+ if(!(callback instanceof Function)) {
+ throw('callback needs to be a function');
+ }
+
+ if(options.root && !(options.root instanceof HTMLElement)) {
+ throw('Root needs to be an HTMLElement');
+ }
+
+ this._callback = callback;
+ this._root = options.root || null;
+ this._rootMargin = options.rootMargin || [0, 0, 0, 0];
+ this._thresholds = options.threshold || [0];
+ this._init();
+ };
+
+ IntersectionObserver.prototype = {
+ //
+ // Public API
+ //
+ get root() {
+ return this._root || document;
+ },
+
+ get rootMargin() {
+ return '0';
+ },
+
+ get thresholds() {
+ if(this._thresholds instanceof Array) {
+ return this._thresholds;
+ }
+ return [this._thresholds];
+ },
+
+ observe: function(target) {
+ if(this._observationTargets.has(target)) {
+ return;
+ }
+ if(!(target instanceof HTMLElement)) {
+ throw('Target needs to be an HTMLelement');
+ }
+
+ var root = this.root;
+ var ancestor = target.parentNode;
+ if(!root.contains(target)) {
+ throw('Target must be descendant of root');
+ }
+ this._mutationObserver.observe(target.parentNode, {
+ attributes: true,
+ childList: true,
+ characterData: true,
+ subtree: true
+ });
+ this._observationTargets.set(target, {});
+ this._update();
+ },
+
+ unobserve: function(target) {
+ this._observationTargets.delete(target);
+ },
+
+ disconnect: function() {
+ this._observationTargets.clear();
+ this.root.removeEventListener('scroll', this._boundUpdate);
+ scope.removeEventListener('resize', this._boundUpdate);
+ this._mutationObserver.disconnect();
+ this._descheduleCallback();
+ },
+
+ takeRecords: function() {
+ this._update();
+ this._descheduleCallback();
+ var copy = this._queue.slice();
+ this._queue = [];
+ return copy;
+ },
+
+ //
+ // Private API
+ //
+ _init: function() {
+ this._observationTargets = new Map();
+ this._boundUpdate = throttle(this._update.bind(this), POLL_INTERVAL);
+ this.root.addEventListener('scroll', this._boundUpdate);
+ scope.addEventListener('resize', this._boundUpdate);
+ this._mutationObserver = new MutationObserver(this._boundUpdate);
+ this._mutationObserver.observe(this.root, {
+ attributes: true,
+ childList: true,
+ characterData: true,
+ subtree: true
+ });
+ this._queue = [];
+ },
+
+ _update: function() {
+ var rootRect = this._rootRect();
+ this._observationTargets.forEach(function(oldIntersectionEntry, target) {
+ var targetRect = getBoundingClientRect(target);
+ var intersectionRect = intersectRects(rootRect, targetRect);
+ if(!intersectionRect) {
+ return;
+ }
+ var targetArea = targetRect.width * targetRect.height;
+ var intersectionArea = intersectionRect.width * intersectionRect.height;
+ var intersectionRatio = intersectionArea / targetArea;
+ if(!this._hasCrossedThreshold(oldIntersectionEntry.intersectionRatio || 0, intersectionRatio)) {
+ return;
+ }
+ var intersectionEntry = {
+ time: scope.performance.now(),
+ rootBounds: rootRect,
+ boundingClientRect: targetRect,
+ intersectionRect: intersectionRect,
+ intersectionRatio: intersectionRatio,
+ target: target
+ };
+ Object.freeze(intersectionEntry);
+ this._queue.push(intersectionEntry);
+ this._scheduleCallback();
+ this._observationTargets.set(target, intersectionEntry);
+ }.bind(this));
+ },
+
+ _scheduleCallback: function() {
+ if(this._timeoutId) {
+ return;
+ }
+ this._timeoutId = scope.setTimeout(function() {
+ this._descheduleCallback();
+ this._callback(this._queue, this);
+ this._queue = [];
+ }.bind(this), POLL_INTERVAL);
+ },
+
+ _descheduleCallback: function() {
+ if(!this._timeoutId) {
+ return;
+ }
+ scope.clearTimeout(this._timeoutId);
+ this._timeoutId = null;
+ },
+
+ _rootRect: function() {
+ if(this._root) {
+ return getBoundingClientRect(this.root);
+ }
+ return {
+ top: 0,
+ left: 0,
+ right: scope.innerWidth,
+ width: scope.innerWidth,
+ bottom: scope.innerHeight,
+ height: scope.innerHeight
+ };
+ },
+
+ _hasCrossedThreshold: function(oldRatio, newRatio) {
+ if(oldRatio === newRatio) {
+ return;
+ }
+ var isOnBoundary = this.thresholds.map(function(threshold) {
+ return threshold == newRatio;
+ }).indexOf(true) !== -1;
+
+ var b1 = this.thresholds.map(function(threshold) {
+ return threshold < oldRatio;
+ });
+ var b2 = this.thresholds.map(function(threshold) {
+ return threshold < newRatio;
+ });
+ var hasCrossedThreshold = b1.map(function(_, idx) {
+ return b1[idx] !== b2[idx]
+ }).indexOf(true) !== -1;
+ return isOnBoundary || hasCrossedThreshold;
+ }
+ };
+
+ var intersectRects = function(rect1, rect2) {
+ var top = Math.max(rect1.top, rect2.top);
+ var bottom = Math.min(rect1.bottom, rect2.bottom);
+ var left = Math.max(rect1.left, rect2.left);
+ var right = Math.min(rect1.right, rect2.right);
+ var intersectionRect = {
+ top: top,
+ bottom: bottom,
+ left: left,
+ right: right,
+ width: right - left,
+ height: bottom - top
+ };
+ if(top > bottom) {
+ intersectionRect.height = 0;
+ }
+ if(left > right) {
+ intersectionRect.width = 0;
+ }
+ return intersectionRect;
+ };
+
+ scope.IntersectionObserver = IntersectionObserver;
+
+ var throttle = function(fn, int) {
+ var timer = null;
+ return function () {
+ if (timer) {
+ return;
+ }
+ timer = setTimeout(function () {
+ fn.apply(this, arguments);
+ timer = null;
+ }.bind(this), int);
+ };
+ };
+
+ var getBoundingClientRect = function(el) {
+ var r = el.getBoundingClientRect();
+ if(!r) {
+ return null;
+ }
+ // Older IE
+ r.width = r.width || r.right - r.left;
+ r.height = r.height || r.bottom - r.top;
+ return r;
+ };
+})(this);
diff --git a/polyfill/intersectionobserver_test.html b/polyfill/intersectionobserver_test.html
new file mode 100644
index 0000000..a156e03
--- /dev/null
+++ b/polyfill/intersectionobserver_test.html
@@ -0,0 +1,241 @@
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/polyfill/test/expect-0.3.1.js b/polyfill/test/expect-0.3.1.js
new file mode 100644
index 0000000..04d8371
--- /dev/null
+++ b/polyfill/test/expect-0.3.1.js
@@ -0,0 +1,1285 @@
+(function (global, module) {
+
+ var exports = module.exports;
+
+ /**
+ * Exports.
+ */
+
+ module.exports = expect;
+ expect.Assertion = Assertion;
+
+ /**
+ * Exports version.
+ */
+
+ expect.version = '0.3.1';
+
+ /**
+ * Possible assertion flags.
+ */
+
+ var flags = {
+ not: ['to', 'be', 'have', 'include', 'only']
+ , to: ['be', 'have', 'include', 'only', 'not']
+ , only: ['have']
+ , have: ['own']
+ , be: ['an']
+ };
+
+ function expect (obj) {
+ return new Assertion(obj);
+ }
+
+ /**
+ * Constructor
+ *
+ * @api private
+ */
+
+ function Assertion (obj, flag, parent) {
+ this.obj = obj;
+ this.flags = {};
+
+ if (undefined != parent) {
+ this.flags[flag] = true;
+
+ for (var i in parent.flags) {
+ if (parent.flags.hasOwnProperty(i)) {
+ this.flags[i] = true;
+ }
+ }
+ }
+
+ var $flags = flag ? flags[flag] : keys(flags)
+ , self = this;
+
+ if ($flags) {
+ for (var i = 0, l = $flags.length; i < l; i++) {
+ // avoid recursion
+ if (this.flags[$flags[i]]) continue;
+
+ var name = $flags[i]
+ , assertion = new Assertion(this.obj, name, this)
+
+ if ('function' == typeof Assertion.prototype[name]) {
+ // clone the function, make sure we dont touch the prot reference
+ var old = this[name];
+ this[name] = function () {
+ return old.apply(self, arguments);
+ };
+
+ for (var fn in Assertion.prototype) {
+ if (Assertion.prototype.hasOwnProperty(fn) && fn != name) {
+ this[name][fn] = bind(assertion[fn], assertion);
+ }
+ }
+ } else {
+ this[name] = assertion;
+ }
+ }
+ }
+ }
+
+ /**
+ * Performs an assertion
+ *
+ * @api private
+ */
+
+ Assertion.prototype.assert = function (truth, msg, error, expected) {
+ var msg = this.flags.not ? error : msg
+ , ok = this.flags.not ? !truth : truth
+ , err;
+
+ if (!ok) {
+ err = new Error(msg.call(this));
+ if (arguments.length > 3) {
+ err.actual = this.obj;
+ err.expected = expected;
+ err.showDiff = true;
+ }
+ throw err;
+ }
+
+ this.and = new Assertion(this.obj);
+ };
+
+ /**
+ * Check if the value is truthy
+ *
+ * @api public
+ */
+
+ Assertion.prototype.ok = function () {
+ this.assert(
+ !!this.obj
+ , function(){ return 'expected ' + i(this.obj) + ' to be truthy' }
+ , function(){ return 'expected ' + i(this.obj) + ' to be falsy' });
+ };
+
+ /**
+ * Creates an anonymous function which calls fn with arguments.
+ *
+ * @api public
+ */
+
+ Assertion.prototype.withArgs = function() {
+ expect(this.obj).to.be.a('function');
+ var fn = this.obj;
+ var args = Array.prototype.slice.call(arguments);
+ return expect(function() { fn.apply(null, args); });
+ };
+
+ /**
+ * Assert that the function throws.
+ *
+ * @param {Function|RegExp} callback, or regexp to match error string against
+ * @api public
+ */
+
+ Assertion.prototype['throw'] =
+ Assertion.prototype.throwError =
+ Assertion.prototype.throwException = function (fn) {
+ expect(this.obj).to.be.a('function');
+
+ var thrown = false
+ , not = this.flags.not;
+
+ try {
+ this.obj();
+ } catch (e) {
+ if (isRegExp(fn)) {
+ var subject = 'string' == typeof e ? e : e.message;
+ if (not) {
+ expect(subject).to.not.match(fn);
+ } else {
+ expect(subject).to.match(fn);
+ }
+ } else if ('function' == typeof fn) {
+ fn(e);
+ }
+ thrown = true;
+ }
+
+ if (isRegExp(fn) && not) {
+ // in the presence of a matcher, ensure the `not` only applies to
+ // the matching.
+ this.flags.not = false;
+ }
+
+ var name = this.obj.name || 'fn';
+ this.assert(
+ thrown
+ , function(){ return 'expected ' + name + ' to throw an exception' }
+ , function(){ return 'expected ' + name + ' not to throw an exception' });
+ };
+
+ /**
+ * Checks if the array is empty.
+ *
+ * @api public
+ */
+
+ Assertion.prototype.empty = function () {
+ var expectation;
+
+ if ('object' == typeof this.obj && null !== this.obj && !isArray(this.obj)) {
+ if ('number' == typeof this.obj.length) {
+ expectation = !this.obj.length;
+ } else {
+ expectation = !keys(this.obj).length;
+ }
+ } else {
+ if ('string' != typeof this.obj) {
+ expect(this.obj).to.be.an('object');
+ }
+
+ expect(this.obj).to.have.property('length');
+ expectation = !this.obj.length;
+ }
+
+ this.assert(
+ expectation
+ , function(){ return 'expected ' + i(this.obj) + ' to be empty' }
+ , function(){ return 'expected ' + i(this.obj) + ' to not be empty' });
+ return this;
+ };
+
+ /**
+ * Checks if the obj exactly equals another.
+ *
+ * @api public
+ */
+
+ Assertion.prototype.be =
+ Assertion.prototype.equal = function (obj) {
+ this.assert(
+ obj === this.obj
+ , function(){ return 'expected ' + i(this.obj) + ' to equal ' + i(obj) }
+ , function(){ return 'expected ' + i(this.obj) + ' to not equal ' + i(obj) });
+ return this;
+ };
+
+ /**
+ * Checks if the obj sortof equals another.
+ *
+ * @api public
+ */
+
+ Assertion.prototype.eql = function (obj) {
+ this.assert(
+ expect.eql(this.obj, obj)
+ , function(){ return 'expected ' + i(this.obj) + ' to sort of equal ' + i(obj) }
+ , function(){ return 'expected ' + i(this.obj) + ' to sort of not equal ' + i(obj) }
+ , obj);
+ return this;
+ };
+
+ /**
+ * Assert within start to finish (inclusive).
+ *
+ * @param {Number} start
+ * @param {Number} finish
+ * @api public
+ */
+
+ Assertion.prototype.within = function (start, finish) {
+ var range = start + '..' + finish;
+ this.assert(
+ this.obj >= start && this.obj <= finish
+ , function(){ return 'expected ' + i(this.obj) + ' to be within ' + range }
+ , function(){ return 'expected ' + i(this.obj) + ' to not be within ' + range });
+ return this;
+ };
+
+ /**
+ * Assert typeof / instance of
+ *
+ * @api public
+ */
+
+ Assertion.prototype.a =
+ Assertion.prototype.an = function (type) {
+ if ('string' == typeof type) {
+ // proper english in error msg
+ var n = /^[aeiou]/.test(type) ? 'n' : '';
+
+ // typeof with support for 'array'
+ this.assert(
+ 'array' == type ? isArray(this.obj) :
+ 'regexp' == type ? isRegExp(this.obj) :
+ 'object' == type
+ ? 'object' == typeof this.obj && null !== this.obj
+ : type == typeof this.obj
+ , function(){ return 'expected ' + i(this.obj) + ' to be a' + n + ' ' + type }
+ , function(){ return 'expected ' + i(this.obj) + ' not to be a' + n + ' ' + type });
+ } else {
+ // instanceof
+ var name = type.name || 'supplied constructor';
+ this.assert(
+ this.obj instanceof type
+ , function(){ return 'expected ' + i(this.obj) + ' to be an instance of ' + name }
+ , function(){ return 'expected ' + i(this.obj) + ' not to be an instance of ' + name });
+ }
+
+ return this;
+ };
+
+ /**
+ * Assert numeric value above _n_.
+ *
+ * @param {Number} n
+ * @api public
+ */
+
+ Assertion.prototype.greaterThan =
+ Assertion.prototype.above = function (n) {
+ this.assert(
+ this.obj > n
+ , function(){ return 'expected ' + i(this.obj) + ' to be above ' + n }
+ , function(){ return 'expected ' + i(this.obj) + ' to be below ' + n });
+ return this;
+ };
+
+ /**
+ * Assert numeric value below _n_.
+ *
+ * @param {Number} n
+ * @api public
+ */
+
+ Assertion.prototype.lessThan =
+ Assertion.prototype.below = function (n) {
+ this.assert(
+ this.obj < n
+ , function(){ return 'expected ' + i(this.obj) + ' to be below ' + n }
+ , function(){ return 'expected ' + i(this.obj) + ' to be above ' + n });
+ return this;
+ };
+
+ /**
+ * Assert string value matches _regexp_.
+ *
+ * @param {RegExp} regexp
+ * @api public
+ */
+
+ Assertion.prototype.match = function (regexp) {
+ this.assert(
+ regexp.exec(this.obj)
+ , function(){ return 'expected ' + i(this.obj) + ' to match ' + regexp }
+ , function(){ return 'expected ' + i(this.obj) + ' not to match ' + regexp });
+ return this;
+ };
+
+ /**
+ * Assert property "length" exists and has value of _n_.
+ *
+ * @param {Number} n
+ * @api public
+ */
+
+ Assertion.prototype.length = function (n) {
+ expect(this.obj).to.have.property('length');
+ var len = this.obj.length;
+ this.assert(
+ n == len
+ , function(){ return 'expected ' + i(this.obj) + ' to have a length of ' + n + ' but got ' + len }
+ , function(){ return 'expected ' + i(this.obj) + ' to not have a length of ' + len });
+ return this;
+ };
+
+ /**
+ * Assert property _name_ exists, with optional _val_.
+ *
+ * @param {String} name
+ * @param {Mixed} val
+ * @api public
+ */
+
+ Assertion.prototype.property = function (name, val) {
+ if (this.flags.own) {
+ this.assert(
+ Object.prototype.hasOwnProperty.call(this.obj, name)
+ , function(){ return 'expected ' + i(this.obj) + ' to have own property ' + i(name) }
+ , function(){ return 'expected ' + i(this.obj) + ' to not have own property ' + i(name) });
+ return this;
+ }
+
+ if (this.flags.not && undefined !== val) {
+ if (undefined === this.obj[name]) {
+ throw new Error(i(this.obj) + ' has no property ' + i(name));
+ }
+ } else {
+ var hasProp;
+ try {
+ hasProp = name in this.obj
+ } catch (e) {
+ hasProp = undefined !== this.obj[name]
+ }
+
+ this.assert(
+ hasProp
+ , function(){ return 'expected ' + i(this.obj) + ' to have a property ' + i(name) }
+ , function(){ return 'expected ' + i(this.obj) + ' to not have a property ' + i(name) });
+ }
+
+ if (undefined !== val) {
+ this.assert(
+ val === this.obj[name]
+ , function(){ return 'expected ' + i(this.obj) + ' to have a property ' + i(name)
+ + ' of ' + i(val) + ', but got ' + i(this.obj[name]) }
+ , function(){ return 'expected ' + i(this.obj) + ' to not have a property ' + i(name)
+ + ' of ' + i(val) });
+ }
+
+ this.obj = this.obj[name];
+ return this;
+ };
+
+ /**
+ * Assert that the array contains _obj_ or string contains _obj_.
+ *
+ * @param {Mixed} obj|string
+ * @api public
+ */
+
+ Assertion.prototype.string =
+ Assertion.prototype.contain = function (obj) {
+ if ('string' == typeof this.obj) {
+ this.assert(
+ ~this.obj.indexOf(obj)
+ , function(){ return 'expected ' + i(this.obj) + ' to contain ' + i(obj) }
+ , function(){ return 'expected ' + i(this.obj) + ' to not contain ' + i(obj) });
+ } else {
+ this.assert(
+ ~indexOf(this.obj, obj)
+ , function(){ return 'expected ' + i(this.obj) + ' to contain ' + i(obj) }
+ , function(){ return 'expected ' + i(this.obj) + ' to not contain ' + i(obj) });
+ }
+ return this;
+ };
+
+ /**
+ * Assert exact keys or inclusion of keys by using
+ * the `.own` modifier.
+ *
+ * @param {Array|String ...} keys
+ * @api public
+ */
+
+ Assertion.prototype.key =
+ Assertion.prototype.keys = function ($keys) {
+ var str
+ , ok = true;
+
+ $keys = isArray($keys)
+ ? $keys
+ : Array.prototype.slice.call(arguments);
+
+ if (!$keys.length) throw new Error('keys required');
+
+ var actual = keys(this.obj)
+ , len = $keys.length;
+
+ // Inclusion
+ ok = every($keys, function (key) {
+ return ~indexOf(actual, key);
+ });
+
+ // Strict
+ if (!this.flags.not && this.flags.only) {
+ ok = ok && $keys.length == actual.length;
+ }
+
+ // Key string
+ if (len > 1) {
+ $keys = map($keys, function (key) {
+ return i(key);
+ });
+ var last = $keys.pop();
+ str = $keys.join(', ') + ', and ' + last;
+ } else {
+ str = i($keys[0]);
+ }
+
+ // Form
+ str = (len > 1 ? 'keys ' : 'key ') + str;
+
+ // Have / include
+ str = (!this.flags.only ? 'include ' : 'only have ') + str;
+
+ // Assertion
+ this.assert(
+ ok
+ , function(){ return 'expected ' + i(this.obj) + ' to ' + str }
+ , function(){ return 'expected ' + i(this.obj) + ' to not ' + str });
+
+ return this;
+ };
+
+ /**
+ * Assert a failure.
+ *
+ * @param {String ...} custom message
+ * @api public
+ */
+ Assertion.prototype.fail = function (msg) {
+ var error = function() { return msg || "explicit failure"; }
+ this.assert(false, error, error);
+ return this;
+ };
+
+ /**
+ * Function bind implementation.
+ */
+
+ function bind (fn, scope) {
+ return function () {
+ return fn.apply(scope, arguments);
+ }
+ }
+
+ /**
+ * Array every compatibility
+ *
+ * @see bit.ly/5Fq1N2
+ * @api public
+ */
+
+ function every (arr, fn, thisObj) {
+ var scope = thisObj || global;
+ for (var i = 0, j = arr.length; i < j; ++i) {
+ if (!fn.call(scope, arr[i], i, arr)) {
+ return false;
+ }
+ }
+ return true;
+ }
+
+ /**
+ * Array indexOf compatibility.
+ *
+ * @see bit.ly/a5Dxa2
+ * @api public
+ */
+
+ function indexOf (arr, o, i) {
+ if (Array.prototype.indexOf) {
+ return Array.prototype.indexOf.call(arr, o, i);
+ }
+
+ if (arr.length === undefined) {
+ return -1;
+ }
+
+ for (var j = arr.length, i = i < 0 ? i + j < 0 ? 0 : i + j : i || 0
+ ; i < j && arr[i] !== o; i++);
+
+ return j <= i ? -1 : i;
+ }
+
+ // https://gist.github.com/1044128/
+ var getOuterHTML = function(element) {
+ if ('outerHTML' in element) return element.outerHTML;
+ var ns = "http://www.w3.org/1999/xhtml";
+ var container = document.createElementNS(ns, '_');
+ var xmlSerializer = new XMLSerializer();
+ var html;
+ if (document.xmlVersion) {
+ return xmlSerializer.serializeToString(element);
+ } else {
+ container.appendChild(element.cloneNode(false));
+ html = container.innerHTML.replace('><', '>' + element.innerHTML + '<');
+ container.innerHTML = '';
+ return html;
+ }
+ };
+
+ // Returns true if object is a DOM element.
+ var isDOMElement = function (object) {
+ if (typeof HTMLElement === 'object') {
+ return object instanceof HTMLElement;
+ } else {
+ return object &&
+ typeof object === 'object' &&
+ object.nodeType === 1 &&
+ typeof object.nodeName === 'string';
+ }
+ };
+
+ /**
+ * Inspects an object.
+ *
+ * @see taken from node.js `util` module (copyright Joyent, MIT license)
+ * @api private
+ */
+
+ function i (obj, showHidden, depth) {
+ var seen = [];
+
+ function stylize (str) {
+ return str;
+ }
+
+ function format (value, recurseTimes) {
+ // Provide a hook for user-specified inspect functions.
+ // Check that value is an object with an inspect function on it
+ if (value && typeof value.inspect === 'function' &&
+ // Filter out the util module, it's inspect function is special
+ value !== exports &&
+ // Also filter out any prototype objects using the circular check.
+ !(value.constructor && value.constructor.prototype === value)) {
+ return value.inspect(recurseTimes);
+ }
+
+ // Primitive types cannot have properties
+ switch (typeof value) {
+ case 'undefined':
+ return stylize('undefined', 'undefined');
+
+ case 'string':
+ var simple = '\'' + json.stringify(value).replace(/^"|"$/g, '')
+ .replace(/'/g, "\\'")
+ .replace(/\\"/g, '"') + '\'';
+ return stylize(simple, 'string');
+
+ case 'number':
+ return stylize('' + value, 'number');
+
+ case 'boolean':
+ return stylize('' + value, 'boolean');
+ }
+ // For some reason typeof null is "object", so special case here.
+ if (value === null) {
+ return stylize('null', 'null');
+ }
+
+ if (isDOMElement(value)) {
+ return getOuterHTML(value);
+ }
+
+ // Look up the keys of the object.
+ var visible_keys = keys(value);
+ var $keys = showHidden ? Object.getOwnPropertyNames(value) : visible_keys;
+
+ // Functions without properties can be shortcutted.
+ if (typeof value === 'function' && $keys.length === 0) {
+ if (isRegExp(value)) {
+ return stylize('' + value, 'regexp');
+ } else {
+ var name = value.name ? ': ' + value.name : '';
+ return stylize('[Function' + name + ']', 'special');
+ }
+ }
+
+ // Dates without properties can be shortcutted
+ if (isDate(value) && $keys.length === 0) {
+ return stylize(value.toUTCString(), 'date');
+ }
+
+ // Error objects can be shortcutted
+ if (value instanceof Error) {
+ return stylize("["+value.toString()+"]", 'Error');
+ }
+
+ var base, type, braces;
+ // Determine the object type
+ if (isArray(value)) {
+ type = 'Array';
+ braces = ['[', ']'];
+ } else {
+ type = 'Object';
+ braces = ['{', '}'];
+ }
+
+ // Make functions say that they are functions
+ if (typeof value === 'function') {
+ var n = value.name ? ': ' + value.name : '';
+ base = (isRegExp(value)) ? ' ' + value : ' [Function' + n + ']';
+ } else {
+ base = '';
+ }
+
+ // Make dates with properties first say the date
+ if (isDate(value)) {
+ base = ' ' + value.toUTCString();
+ }
+
+ if ($keys.length === 0) {
+ return braces[0] + base + braces[1];
+ }
+
+ if (recurseTimes < 0) {
+ if (isRegExp(value)) {
+ return stylize('' + value, 'regexp');
+ } else {
+ return stylize('[Object]', 'special');
+ }
+ }
+
+ seen.push(value);
+
+ var output = map($keys, function (key) {
+ var name, str;
+ if (value.__lookupGetter__) {
+ if (value.__lookupGetter__(key)) {
+ if (value.__lookupSetter__(key)) {
+ str = stylize('[Getter/Setter]', 'special');
+ } else {
+ str = stylize('[Getter]', 'special');
+ }
+ } else {
+ if (value.__lookupSetter__(key)) {
+ str = stylize('[Setter]', 'special');
+ }
+ }
+ }
+ if (indexOf(visible_keys, key) < 0) {
+ name = '[' + key + ']';
+ }
+ if (!str) {
+ if (indexOf(seen, value[key]) < 0) {
+ if (recurseTimes === null) {
+ str = format(value[key]);
+ } else {
+ str = format(value[key], recurseTimes - 1);
+ }
+ if (str.indexOf('\n') > -1) {
+ if (isArray(value)) {
+ str = map(str.split('\n'), function (line) {
+ return ' ' + line;
+ }).join('\n').substr(2);
+ } else {
+ str = '\n' + map(str.split('\n'), function (line) {
+ return ' ' + line;
+ }).join('\n');
+ }
+ }
+ } else {
+ str = stylize('[Circular]', 'special');
+ }
+ }
+ if (typeof name === 'undefined') {
+ if (type === 'Array' && key.match(/^\d+$/)) {
+ return str;
+ }
+ name = json.stringify('' + key);
+ if (name.match(/^"([a-zA-Z_][a-zA-Z_0-9]*)"$/)) {
+ name = name.substr(1, name.length - 2);
+ name = stylize(name, 'name');
+ } else {
+ name = name.replace(/'/g, "\\'")
+ .replace(/\\"/g, '"')
+ .replace(/(^"|"$)/g, "'");
+ name = stylize(name, 'string');
+ }
+ }
+
+ return name + ': ' + str;
+ });
+
+ seen.pop();
+
+ var numLinesEst = 0;
+ var length = reduce(output, function (prev, cur) {
+ numLinesEst++;
+ if (indexOf(cur, '\n') >= 0) numLinesEst++;
+ return prev + cur.length + 1;
+ }, 0);
+
+ if (length > 50) {
+ output = braces[0] +
+ (base === '' ? '' : base + '\n ') +
+ ' ' +
+ output.join(',\n ') +
+ ' ' +
+ braces[1];
+
+ } else {
+ output = braces[0] + base + ' ' + output.join(', ') + ' ' + braces[1];
+ }
+
+ return output;
+ }
+ return format(obj, (typeof depth === 'undefined' ? 2 : depth));
+ }
+
+ expect.stringify = i;
+
+ function isArray (ar) {
+ return Object.prototype.toString.call(ar) === '[object Array]';
+ }
+
+ function isRegExp(re) {
+ var s;
+ try {
+ s = '' + re;
+ } catch (e) {
+ return false;
+ }
+
+ return re instanceof RegExp || // easy case
+ // duck-type for context-switching evalcx case
+ typeof(re) === 'function' &&
+ re.constructor.name === 'RegExp' &&
+ re.compile &&
+ re.test &&
+ re.exec &&
+ s.match(/^\/.*\/[gim]{0,3}$/);
+ }
+
+ function isDate(d) {
+ return d instanceof Date;
+ }
+
+ function keys (obj) {
+ if (Object.keys) {
+ return Object.keys(obj);
+ }
+
+ var keys = [];
+
+ for (var i in obj) {
+ if (Object.prototype.hasOwnProperty.call(obj, i)) {
+ keys.push(i);
+ }
+ }
+
+ return keys;
+ }
+
+ function map (arr, mapper, that) {
+ if (Array.prototype.map) {
+ return Array.prototype.map.call(arr, mapper, that);
+ }
+
+ var other= new Array(arr.length);
+
+ for (var i= 0, n = arr.length; i= 2) {
+ var rv = arguments[1];
+ } else {
+ do {
+ if (i in this) {
+ rv = this[i++];
+ break;
+ }
+
+ // if array contains no values, no initial value to return
+ if (++i >= len)
+ throw new TypeError();
+ } while (true);
+ }
+
+ for (; i < len; i++) {
+ if (i in this)
+ rv = fun.call(null, rv, this[i], i, this);
+ }
+
+ return rv;
+ }
+
+ /**
+ * Asserts deep equality
+ *
+ * @see taken from node.js `assert` module (copyright Joyent, MIT license)
+ * @api private
+ */
+
+ expect.eql = function eql(actual, expected) {
+ // 7.1. All identical values are equivalent, as determined by ===.
+ if (actual === expected) {
+ return true;
+ } else if ('undefined' != typeof Buffer
+ && Buffer.isBuffer(actual) && Buffer.isBuffer(expected)) {
+ if (actual.length != expected.length) return false;
+
+ for (var i = 0; i < actual.length; i++) {
+ if (actual[i] !== expected[i]) return false;
+ }
+
+ return true;
+
+ // 7.2. If the expected value is a Date object, the actual value is
+ // equivalent if it is also a Date object that refers to the same time.
+ } else if (actual instanceof Date && expected instanceof Date) {
+ return actual.getTime() === expected.getTime();
+
+ // 7.3. Other pairs that do not both pass typeof value == "object",
+ // equivalence is determined by ==.
+ } else if (typeof actual != 'object' && typeof expected != 'object') {
+ return actual == expected;
+ // If both are regular expression use the special `regExpEquiv` method
+ // to determine equivalence.
+ } else if (isRegExp(actual) && isRegExp(expected)) {
+ return regExpEquiv(actual, expected);
+ // 7.4. For all other Object pairs, including Array objects, equivalence is
+ // determined by having the same number of owned properties (as verified
+ // with Object.prototype.hasOwnProperty.call), the same set of keys
+ // (although not necessarily the same order), equivalent values for every
+ // corresponding key, and an identical "prototype" property. Note: this
+ // accounts for both named and indexed properties on Arrays.
+ } else {
+ return objEquiv(actual, expected);
+ }
+ };
+
+ function isUndefinedOrNull (value) {
+ return value === null || value === undefined;
+ }
+
+ function isArguments (object) {
+ return Object.prototype.toString.call(object) == '[object Arguments]';
+ }
+
+ function regExpEquiv (a, b) {
+ return a.source === b.source && a.global === b.global &&
+ a.ignoreCase === b.ignoreCase && a.multiline === b.multiline;
+ }
+
+ function objEquiv (a, b) {
+ if (isUndefinedOrNull(a) || isUndefinedOrNull(b))
+ return false;
+ // an identical "prototype" property.
+ if (a.prototype !== b.prototype) return false;
+ //~~~I've managed to break Object.keys through screwy arguments passing.
+ // Converting to array solves the problem.
+ if (isArguments(a)) {
+ if (!isArguments(b)) {
+ return false;
+ }
+ a = pSlice.call(a);
+ b = pSlice.call(b);
+ return expect.eql(a, b);
+ }
+ try{
+ var ka = keys(a),
+ kb = keys(b),
+ key, i;
+ } catch (e) {//happens when one is a string literal and the other isn't
+ return false;
+ }
+ // having the same number of owned properties (keys incorporates hasOwnProperty)
+ if (ka.length != kb.length)
+ return false;
+ //the same set of keys (although not necessarily the same order),
+ ka.sort();
+ kb.sort();
+ //~~~cheap key test
+ for (i = ka.length - 1; i >= 0; i--) {
+ if (ka[i] != kb[i])
+ return false;
+ }
+ //equivalent values for every corresponding key, and
+ //~~~possibly expensive deep test
+ for (i = ka.length - 1; i >= 0; i--) {
+ key = ka[i];
+ if (!expect.eql(a[key], b[key]))
+ return false;
+ }
+ return true;
+ }
+
+ var json = (function () {
+ "use strict";
+
+ if ('object' == typeof JSON && JSON.parse && JSON.stringify) {
+ return {
+ parse: nativeJSON.parse
+ , stringify: nativeJSON.stringify
+ }
+ }
+
+ var JSON = {};
+
+ function f(n) {
+ // Format integers to have at least two digits.
+ return n < 10 ? '0' + n : n;
+ }
+
+ function date(d, key) {
+ return isFinite(d.valueOf()) ?
+ d.getUTCFullYear() + '-' +
+ f(d.getUTCMonth() + 1) + '-' +
+ f(d.getUTCDate()) + 'T' +
+ f(d.getUTCHours()) + ':' +
+ f(d.getUTCMinutes()) + ':' +
+ f(d.getUTCSeconds()) + 'Z' : null;
+ }
+
+ var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
+ escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
+ gap,
+ indent,
+ meta = { // table of character substitutions
+ '\b': '\\b',
+ '\t': '\\t',
+ '\n': '\\n',
+ '\f': '\\f',
+ '\r': '\\r',
+ '"' : '\\"',
+ '\\': '\\\\'
+ },
+ rep;
+
+
+ function quote(string) {
+
+ // If the string contains no control characters, no quote characters, and no
+ // backslash characters, then we can safely slap some quotes around it.
+ // Otherwise we must also replace the offending characters with safe escape
+ // sequences.
+
+ escapable.lastIndex = 0;
+ return escapable.test(string) ? '"' + string.replace(escapable, function (a) {
+ var c = meta[a];
+ return typeof c === 'string' ? c :
+ '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
+ }) + '"' : '"' + string + '"';
+ }
+
+
+ function str(key, holder) {
+
+ // Produce a string from holder[key].
+
+ var i, // The loop counter.
+ k, // The member key.
+ v, // The member value.
+ length,
+ mind = gap,
+ partial,
+ value = holder[key];
+
+ // If the value has a toJSON method, call it to obtain a replacement value.
+
+ if (value instanceof Date) {
+ value = date(key);
+ }
+
+ // If we were called with a replacer function, then call the replacer to
+ // obtain a replacement value.
+
+ if (typeof rep === 'function') {
+ value = rep.call(holder, key, value);
+ }
+
+ // What happens next depends on the value's type.
+
+ switch (typeof value) {
+ case 'string':
+ return quote(value);
+
+ case 'number':
+
+ // JSON numbers must be finite. Encode non-finite numbers as null.
+
+ return isFinite(value) ? String(value) : 'null';
+
+ case 'boolean':
+ case 'null':
+
+ // If the value is a boolean or null, convert it to a string. Note:
+ // typeof null does not produce 'null'. The case is included here in
+ // the remote chance that this gets fixed someday.
+
+ return String(value);
+
+ // If the type is 'object', we might be dealing with an object or an array or
+ // null.
+
+ case 'object':
+
+ // Due to a specification blunder in ECMAScript, typeof null is 'object',
+ // so watch out for that case.
+
+ if (!value) {
+ return 'null';
+ }
+
+ // Make an array to hold the partial results of stringifying this object value.
+
+ gap += indent;
+ partial = [];
+
+ // Is the value an array?
+
+ if (Object.prototype.toString.apply(value) === '[object Array]') {
+
+ // The value is an array. Stringify every element. Use null as a placeholder
+ // for non-JSON values.
+
+ length = value.length;
+ for (i = 0; i < length; i += 1) {
+ partial[i] = str(i, value) || 'null';
+ }
+
+ // Join all of the elements together, separated with commas, and wrap them in
+ // brackets.
+
+ v = partial.length === 0 ? '[]' : gap ?
+ '[\n' + gap + partial.join(',\n' + gap) + '\n' + mind + ']' :
+ '[' + partial.join(',') + ']';
+ gap = mind;
+ return v;
+ }
+
+ // If the replacer is an array, use it to select the members to be stringified.
+
+ if (rep && typeof rep === 'object') {
+ length = rep.length;
+ for (i = 0; i < length; i += 1) {
+ if (typeof rep[i] === 'string') {
+ k = rep[i];
+ v = str(k, value);
+ if (v) {
+ partial.push(quote(k) + (gap ? ': ' : ':') + v);
+ }
+ }
+ }
+ } else {
+
+ // Otherwise, iterate through all of the keys in the object.
+
+ for (k in value) {
+ if (Object.prototype.hasOwnProperty.call(value, k)) {
+ v = str(k, value);
+ if (v) {
+ partial.push(quote(k) + (gap ? ': ' : ':') + v);
+ }
+ }
+ }
+ }
+
+ // Join all of the member texts together, separated with commas,
+ // and wrap them in braces.
+
+ v = partial.length === 0 ? '{}' : gap ?
+ '{\n' + gap + partial.join(',\n' + gap) + '\n' + mind + '}' :
+ '{' + partial.join(',') + '}';
+ gap = mind;
+ return v;
+ }
+ }
+
+ // If the JSON object does not yet have a stringify method, give it one.
+
+ JSON.stringify = function (value, replacer, space) {
+
+ // The stringify method takes a value and an optional replacer, and an optional
+ // space parameter, and returns a JSON text. The replacer can be a function
+ // that can replace values, or an array of strings that will select the keys.
+ // A default replacer method can be provided. Use of the space parameter can
+ // produce text that is more easily readable.
+
+ var i;
+ gap = '';
+ indent = '';
+
+ // If the space parameter is a number, make an indent string containing that
+ // many spaces.
+
+ if (typeof space === 'number') {
+ for (i = 0; i < space; i += 1) {
+ indent += ' ';
+ }
+
+ // If the space parameter is a string, it will be used as the indent string.
+
+ } else if (typeof space === 'string') {
+ indent = space;
+ }
+
+ // If there is a replacer, it must be a function or an array.
+ // Otherwise, throw an error.
+
+ rep = replacer;
+ if (replacer && typeof replacer !== 'function' &&
+ (typeof replacer !== 'object' ||
+ typeof replacer.length !== 'number')) {
+ throw new Error('JSON.stringify');
+ }
+
+ // Make a fake root object containing our value under the key of ''.
+ // Return the result of stringifying the value.
+
+ return str('', {'': value});
+ };
+
+ // If the JSON object does not yet have a parse method, give it one.
+
+ JSON.parse = function (text, reviver) {
+ // The parse method takes a text and an optional reviver function, and returns
+ // a JavaScript value if the text is a valid JSON text.
+
+ var j;
+
+ function walk(holder, key) {
+
+ // The walk method is used to recursively walk the resulting structure so
+ // that modifications can be made.
+
+ var k, v, value = holder[key];
+ if (value && typeof value === 'object') {
+ for (k in value) {
+ if (Object.prototype.hasOwnProperty.call(value, k)) {
+ v = walk(value, k);
+ if (v !== undefined) {
+ value[k] = v;
+ } else {
+ delete value[k];
+ }
+ }
+ }
+ }
+ return reviver.call(holder, key, value);
+ }
+
+
+ // Parsing happens in four stages. In the first stage, we replace certain
+ // Unicode characters with escape sequences. JavaScript handles many characters
+ // incorrectly, either silently deleting them, or treating them as line endings.
+
+ text = String(text);
+ cx.lastIndex = 0;
+ if (cx.test(text)) {
+ text = text.replace(cx, function (a) {
+ return '\\u' +
+ ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
+ });
+ }
+
+ // In the second stage, we run the text against regular expressions that look
+ // for non-JSON patterns. We are especially concerned with '()' and 'new'
+ // because they can cause invocation, and '=' because it can cause mutation.
+ // But just to be safe, we want to reject all unexpected forms.
+
+ // We split the second stage into 4 regexp operations in order to work around
+ // crippling inefficiencies in IE's and Safari's regexp engines. First we
+ // replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
+ // replace all simple value tokens with ']' characters. Third, we delete all
+ // open brackets that follow a colon or comma or that begin the text. Finally,
+ // we look to see that the remaining characters are only whitespace or ']' or
+ // ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
+
+ if (/^[\],:{}\s]*$/
+ .test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@')
+ .replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']')
+ .replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
+
+ // In the third stage we use the eval function to compile the text into a
+ // JavaScript structure. The '{' operator is subject to a syntactic ambiguity
+ // in JavaScript: it can begin a block or an object literal. We wrap the text
+ // in parens to eliminate the ambiguity.
+
+ j = eval('(' + text + ')');
+
+ // In the optional fourth stage, we recursively walk the new structure, passing
+ // each name/value pair to a reviver function for possible transformation.
+
+ return typeof reviver === 'function' ?
+ walk({'': j}, '') : j;
+ }
+
+ // If the text is not JSON parseable, then a SyntaxError is thrown.
+
+ throw new SyntaxError('JSON.parse');
+ };
+
+ return JSON;
+ })();
+
+ if ('undefined' != typeof window) {
+ window.expect = module.exports;
+ }
+
+})(
+ this
+ , 'undefined' != typeof module ? module : {exports: {}}
+);