kiwix-js-pwa/www/js/lib/promisePolyfill.js

/*
	Yaku v0.19.3
	(c) 2015 Yad Smood. http://ysmood.org
	License MIT
*/
/*
	Yaku v0.17.9
	(c) 2015 Yad Smood. http://ysmood.org
	License MIT
*/

(function () {
	'use strict';

	var $undefined
	, $null = null
	, isBrowser = typeof self === 'object'
	, root = self
	, nativePromise = root.Promise
	, process = root.process
	, console = root.console
	, isLongStackTrace = true
	, Arr = Array
	, Err = Error

	, $rejected = 1
	, $resolved = 2
	, $pending = 3

	, $Symbol = 'Symbol'
	, $iterator = 'iterator'
	, $species = 'species'
	, $speciesKey = $Symbol + '(' + $species + ')'
	, $return = 'return'

	, $unhandled = '_uh'
	, $promiseTrace = '_pt'
	, $settlerTrace = '_st'

	, $invalidThis = 'Invalid this'
	, $invalidArgument = 'Invalid argument'
	, $fromPrevious = '\nFrom previous '
	, $promiseCircularChain = 'Chaining cycle detected for promise'
	, $unhandledRejectionMsg = 'Uncaught (in promise)'
	, $rejectionHandled = 'rejectionHandled'
	, $unhandledRejection = 'unhandledRejection'

	, $tryCatchFn
	, $tryCatchThis
	, $tryErr = { e: $null }
	, $noop = function () {}
	, $cleanStackReg = /^.+\/node_modules\/yaku\/.+\n?/mg
	;

	/**
	* This class follows the [Promises/A+](https://promisesaplus.com) and
	* [ES6](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-promise-objects) spec
	* with some extra helpers.
	* @param  {Function} executor Function object with two arguments resolve, reject.
	* The first argument fulfills the promise, the second argument rejects it.
	* We can call these functions, once our operation is completed.
	*/
	var Yaku = function (executor) {
	var self = this,
		err;

	// "this._s" is the internao state of: pending, resolved or rejected
	// "this._v" is the internal value

	if (!isObject(self) || self._s !== $undefined)
		throw genTypeError($invalidThis);

	self._s = $pending;

	if (isLongStackTrace) self[$promiseTrace] = genTraceInfo();

	if (executor !== $noop) {
		if (!isFunction(executor))
			throw genTypeError($invalidArgument);

		err = genTryCatcher(executor)(
			genSettler(self, $resolved),
			genSettler(self, $rejected)
		);

		if (err === $tryErr)
			settlePromise(self, $rejected, err.e);
	}
	};

	Yaku['default'] = Yaku;

	extend(Yaku.prototype, {
	/**
		* Appends fulfillment and rejection handlers to the promise,
		* and returns a new promise resolving to the return value of the called handler.
		* @param  {Function} onFulfilled Optional. Called when the Promise is resolved.
		* @param  {Function} onRejected  Optional. Called when the Promise is rejected.
		* @return {Yaku} It will return a new Yaku which will resolve or reject after
		* @example
		* the current Promise.
		* ```js
		* var Promise = require('yaku');
		* var p = Promise.resolve(10);
		*
		* p.then((v) => {
		*     console.log(v);
		* });
		* ```
		*/
	then: function (onFulfilled, onRejected) {
		if (this._s === undefined) throw genTypeError();

		return addHandler(
			this,
			newCapablePromise(Yaku.speciesConstructor(this, Yaku)),
			onFulfilled,
			onRejected
		);
	},

	/**
		* The `catch()` method returns a Promise and deals with rejected cases only.
		* It behaves the same as calling `Promise.prototype.then(undefined, onRejected)`.
		* @param  {Function} onRejected A Function called when the Promise is rejected.
		* This function has one argument, the rejection reason.
		* @return {Yaku} A Promise that deals with rejected cases only.
		* @example
		* ```js
		* var Promise = require('yaku');
		* var p = Promise.reject(new Error("ERR"));
		*
		* p['catch']((v) => {
		*     console.log(v);
		* });
		* ```
		*/
	'catch': function (onRejected) {
		return this.then($undefined, onRejected);
	},

	/**
		* Register a callback to be invoked when a promise is settled (either fulfilled or rejected).
		* Similar with the try-catch-finally, it's often used for cleanup.
		* @param  {Function} onFinally A Function called when the Promise is settled.
		* It will not receive any argument.
		* @return {Yaku} A Promise that will reject if onFinally throws an error or returns a rejected promise.
		* Else it will resolve previous promise's final state (either fulfilled or rejected).
		* @example
		* ```js
		* var Promise = require('yaku');
		* var p = Math.random() > 0.5 ? Promise.resolve() : Promise.reject();
		* p.finally(() => {
		*     console.log('finally');
		* });
		* ```
		*/
	'finally': function (onFinally) {
		return this.then(function (val) {
			return Yaku.resolve(onFinally()).then(function () {
				return val;
			});
		}, function (err) {
			return Yaku.resolve(onFinally()).then(function () {
				throw err;
			});
		});
	},

	// The number of current promises that attach to this Yaku instance.
	_c: 0,

	// The parent Yaku.
	_p: $null
	});

	/**
	* The `Promise.resolve(value)` method returns a Promise object that is resolved with the given value.
	* If the value is a thenable (i.e. has a then method), the returned promise will "follow" that thenable,
	* adopting its eventual state; otherwise the returned promise will be fulfilled with the value.
	* @param  {Any} value Argument to be resolved by this Promise.
	* Can also be a Promise or a thenable to resolve.
	* @return {Yaku}
	* @example
	* ```js
	* var Promise = require('yaku');
	* var p = Promise.resolve(10);
	* ```
	*/
	Yaku.resolve = function (val) {
	return isYaku(val) ? val : settleWithX(newCapablePromise(this), val);
	};

	/**
	* The `Promise.reject(reason)` method returns a Promise object that is rejected with the given reason.
	* @param  {Any} reason Reason why this Promise rejected.
	* @return {Yaku}
	* @example
	* ```js
	* var Promise = require('yaku');
	* var p = Promise.reject(new Error("ERR"));
	* ```
	*/
	Yaku.reject = function (reason) {
	return settlePromise(newCapablePromise(this), $rejected, reason);
	};

	/**
	* The `Promise.race(iterable)` method returns a promise that resolves or rejects
	* as soon as one of the promises in the iterable resolves or rejects,
	* with the value or reason from that promise.
	* @param  {iterable} iterable An iterable object, such as an Array.
	* @return {Yaku} The race function returns a Promise that is settled
	* the same way as the first passed promise to settle.
	* It resolves or rejects, whichever happens first.
	* @example
	* ```js
	* var Promise = require('yaku');
	* Promise.race([
	*     123,
	*     Promise.resolve(0)
	* ])
	* .then((value) => {
	*     console.log(value); // => 123
	* });
	* ```
	*/
	Yaku.race = function (iterable) {
	var self = this
		, p = newCapablePromise(self)

		, resolve = function (val) {
			settlePromise(p, $resolved, val);
		}

		, reject = function (val) {
			settlePromise(p, $rejected, val);
		}

		, ret = genTryCatcher(each)(iterable, function (v) {
			self.resolve(v).then(resolve, reject);
		});

	if (ret === $tryErr) return self.reject(ret.e);

	return p;
	};

	/**
	* The `Promise.all(iterable)` method returns a promise that resolves when
	* all of the promises in the iterable argument have resolved.
	*
	* The result is passed as an array of values from all the promises.
	* If something passed in the iterable array is not a promise,
	* it's converted to one by Promise.resolve. If any of the passed in promises rejects,
	* the all Promise immediately rejects with the value of the promise that rejected,
	* discarding all the other promises whether or not they have resolved.
	* @param  {iterable} iterable An iterable object, such as an Array.
	* @return {Yaku}
	* @example
	* ```js
	* var Promise = require('yaku');
	* Promise.all([
	*     123,
	*     Promise.resolve(0)
	* ])
	* .then((values) => {
	*     console.log(values); // => [123, 0]
	* });
	* ```
	* @example
	* Use with iterable.
	* ```js
	* var Promise = require('yaku');
	* Promise.all((function * () {
	*     yield 10;
	*     yield new Promise(function (r) { setTimeout(r, 1000, "OK") });
	* })())
	* .then((values) => {
	*     console.log(values); // => [123, 0]
	* });
	* ```
	*/
	Yaku.all = function (iterable) {
	var self = this
		, p1 = newCapablePromise(self)
		, res = []
		, ret
	;

	function reject (reason) {
		settlePromise(p1, $rejected, reason);
	}

	ret = genTryCatcher(each)(iterable, function (item, i) {
		self.resolve(item).then(function (value) {
			res[i] = value;
			if (!--ret) settlePromise(p1, $resolved, res);
		}, reject);
	});

	if (ret === $tryErr) return self.reject(ret.e);

	if (!ret) settlePromise(p1, $resolved, []);

	return p1;
	};

	/**
	* The ES6 Symbol object that Yaku should use, by default it will use the
	* global one.
	* @type {Object}
	* @example
	* ```js
	* var core = require("core-js/library");
	* var Promise = require("yaku");
	* Promise.Symbol = core.Symbol;
	* ```
	*/
	Yaku.Symbol = root[$Symbol] || {};

	// To support browsers that don't support `Object.defineProperty`.
	genTryCatcher(function () {
	Object.defineProperty(Yaku, getSpecies(), {
		get: function () { return this; }
	});
	})();

	/**
	* Use this api to custom the species behavior.
	* https://tc39.github.io/ecma262/#sec-speciesconstructor
	* @param {Any} O The current this object.
	* @param {Function} defaultConstructor
	*/
	Yaku.speciesConstructor = function (O, D) {
	var C = O.constructor;

	return C ? (C[getSpecies()] || D) : D;
	};

	/**
	* Catch all possibly unhandled rejections. If you want to use specific
	* format to display the error stack, overwrite it.
	* If it is set, auto `console.error` unhandled rejection will be disabled.
	* @param {Any} reason The rejection reason.
	* @param {Yaku} p The promise that was rejected.
	* @example
	* ```js
	* var Promise = require('yaku');
	* Promise.unhandledRejection = (reason) => {
	*     console.error(reason);
	* };
	*
	* // The console will log an unhandled rejection error message.
	* Promise.reject('my reason');
	*
	* // The below won't log the unhandled rejection error message.
	* Promise.reject('v')["catch"](() => {});
	* ```
	*/
	Yaku.unhandledRejection = function (reason, p) {
	console && console.error(
		$unhandledRejectionMsg,
		isLongStackTrace ? p.longStack : genStackInfo(reason, p)
	);
	};

	/**
	* Emitted whenever a Promise was rejected and an error handler was
	* attached to it (for example with `["catch"]()`) later than after an event loop turn.
	* @param {Any} reason The rejection reason.
	* @param {Yaku} p The promise that was rejected.
	*/
	Yaku.rejectionHandled = $noop;

	/**
	* It is used to enable the long stack trace.
	* Once it is enabled, it can't be reverted.
	* While it is very helpful in development and testing environments,
	* it is not recommended to use it in production. It will slow down
	* application and eat up memory.
	* It will add an extra property `longStack` to the Error object.
	* @example
	* ```js
	* var Promise = require('yaku');
	* Promise.enableLongStackTrace();
	* Promise.reject(new Error("err"))["catch"]((err) => {
	*     console.log(err.longStack);
	* });
	* ```
	*/
	Yaku.enableLongStackTrace = function () {
	isLongStackTrace = true;
	};

	/**
	* Only Node has `process.nextTick` function. For browser there are
	* so many ways to polyfill it. Yaku won't do it for you, instead you
	* can choose what you prefer. For example, this project
	* [next-tick](https://github.com/medikoo/next-tick).
	* By default, Yaku will use `process.nextTick` on Node, `setTimeout` on browser.
	* @type {Function}
	* @example
	* ```js
	* var Promise = require('yaku');
	* Promise.nextTick = require('next-tick');
	* ```
	* @example
	* You can even use sync resolution if you really know what you are doing.
	* ```js
	* var Promise = require('yaku');
	* Promise.nextTick = fn => fn();
	* ```
	*/
	Yaku.nextTick = isBrowser ?
	function (fn) {
		nativePromise ?
			new nativePromise(function (resolve) { resolve(); }).then(fn) :
			setTimeout(fn);
	} :
	process.nextTick;

	// ********************** Private **********************

	Yaku._s = 1;

	/**
	* All static variable name will begin with `$`. Such as `$rejected`.
	* @private
	*/

	// ******************************* Utils ********************************

	function getSpecies () {
	return Yaku[$Symbol][$species] || $speciesKey;
	}

	function extend (src, target) {
	for (var k in target) {
		src[k] = target[k];
	}
	}

	function isObject (obj) {
	return obj && typeof obj === 'object';
	}

	function isFunction (obj) {
	return typeof obj === 'function';
	}

	function isInstanceOf (a, b) {
	return a instanceof b;
	}

	function isError (obj) {
	return isInstanceOf(obj, Err);
	}

	function ensureType (obj, fn, msg) {
	if (!fn(obj)) throw genTypeError(msg);
	}

	/**
	* Wrap a function into a try-catch.
	* @private
	* @return {Any | $tryErr}
	*/
	function tryCatcher () {
	try {
		return $tryCatchFn.apply($tryCatchThis, arguments);
	} catch (e) {
		$tryErr.e = e;
		return $tryErr;
	}
	}

	/**
	* Generate a try-catch wrapped function.
	* @private
	* @param  {Function} fn
	* @return {Function}
	*/
	function genTryCatcher (fn, self) {
	$tryCatchFn = fn;
	$tryCatchThis = self;
	return tryCatcher;
	}

	/**
	* Generate a scheduler.
	* @private
	* @param  {Integer}  initQueueSize
	* @param  {Function} fn `(Yaku, Value) ->` The schedule handler.
	* @return {Function} `(Yaku, Value) ->` The scheduler.
	*/
	function genScheduler (initQueueSize, fn) {
	/**
		* All async promise will be scheduled in
		* here, so that they can be execute on the next tick.
		* @private
		*/
	var fnQueue = Arr(initQueueSize)
		, fnQueueLen = 0;

	/**
		* Run all queued functions.
		* @private
		*/
	function flush () {
		var i = 0;
		while (i < fnQueueLen) {
			fn(fnQueue[i], fnQueue[i + 1]);
			fnQueue[i++] = $undefined;
			fnQueue[i++] = $undefined;
		}

		fnQueueLen = 0;
		if (fnQueue.length > initQueueSize) fnQueue.length = initQueueSize;
	}

	return function (v, arg) {
		fnQueue[fnQueueLen++] = v;
		fnQueue[fnQueueLen++] = arg;

		if (fnQueueLen === 2) Yaku.nextTick(flush);
	};
	}

	/**
	* Generate a iterator
	* @param  {Any} obj
	* @private
	* @return {Object || TypeError}
	*/
	function each (iterable, fn) {
	var len
		, i = 0
		, iter
		, item
		, ret
	;

	if (!iterable) throw genTypeError($invalidArgument);

	var gen = iterable[Yaku[$Symbol][$iterator]];
	if (isFunction(gen))
		iter = gen.call(iterable);
	else if (isFunction(iterable.next)) {
		iter = iterable;
	}
	else if (isInstanceOf(iterable, Arr)) {
		len = iterable.length;
		while (i < len) {
			fn(iterable[i], i++);
		}
		return i;
	} else
		throw genTypeError($invalidArgument);

	while (!(item = iter.next()).done) {
		ret = genTryCatcher(fn)(item.value, i++);
		if (ret === $tryErr) {
			isFunction(iter[$return]) && iter[$return]();
			throw ret.e;
		}
	}

	return i;
	}

	/**
	* Generate type error object.
	* @private
	* @param  {String} msg
	* @return {TypeError}
	*/
	function genTypeError (msg) {
	return new TypeError(msg);
	}

	function genTraceInfo (noTitle) {
	return (noTitle ? '' : $fromPrevious) + new Err().stack;
	}


	// *************************** Promise Helpers ****************************

	/**
	* Resolve the value returned by onFulfilled or onRejected.
	* @private
	* @param {Yaku} p1
	* @param {Yaku} p2
	*/
	var scheduleHandler = genScheduler(999, function (p1, p2) {
	var x, handler;

	// 2.2.2
	// 2.2.3
	handler = p1._s !== $rejected ? p2._onFulfilled : p2._onRejected;

	// 2.2.7.3
	// 2.2.7.4
	if (handler === $undefined) {
		settlePromise(p2, p1._s, p1._v);
		return;
	}

	// 2.2.7.1
	x = genTryCatcher(callHanler)(handler, p1._v);
	if (x === $tryErr) {
		// 2.2.7.2
		settlePromise(p2, $rejected, x.e);
		return;
	}

	settleWithX(p2, x);
	});

	var scheduleUnhandledRejection = genScheduler(9, function (p) {
	if (!hashOnRejected(p)) {
		p[$unhandled] = 1;
		emitEvent($unhandledRejection, p);
	}
	});

	function emitEvent (name, p) {
	var browserEventName = 'on' + name.toLowerCase()
		, browserHandler = root[browserEventName];

	if (process && process.listeners(name).length)
		name === $unhandledRejection ?
			process.emit(name, p._v, p) : process.emit(name, p);
	else if (browserHandler)
		browserHandler({ reason: p._v, promise: p });
	else
		Yaku[name](p._v, p);
	}

	function isYaku (val) { return val && val._s; }

	function newCapablePromise (Constructor) {
	if (isYaku(Constructor)) return new Constructor($noop);

	var p, r, j;
	p = new Constructor(function (resolve, reject) {
		if (p) throw genTypeError();

		r = resolve;
		j = reject;
	});

	ensureType(r, isFunction);
	ensureType(j, isFunction);

	return p;
	}

	/**
	* It will produce a settlePromise function to user.
	* Such as the resolve and reject in this `new Yaku (resolve, reject) ->`.
	* @private
	* @param  {Yaku} self
	* @param  {Integer} state The value is one of `$pending`, `$resolved` or `$rejected`.
	* @return {Function} `(value) -> undefined` A resolve or reject function.
	*/
	function genSettler (self, state) {
	var isCalled = false;
	return function (value) {
		if (isCalled) return;
		isCalled = true;

		if (isLongStackTrace)
			self[$settlerTrace] = genTraceInfo(true);

		if (state === $resolved)
			settleWithX(self, value);
		else
			settlePromise(self, state, value);
	};
	}

	/**
	* Link the promise1 to the promise2.
	* @private
	* @param {Yaku} p1
	* @param {Yaku} p2
	* @param {Function} onFulfilled
	* @param {Function} onRejected
	*/
	function addHandler (p1, p2, onFulfilled, onRejected) {
	// 2.2.1
	if (isFunction(onFulfilled))
		p2._onFulfilled = onFulfilled;
	if (isFunction(onRejected)) {
		if (p1[$unhandled]) emitEvent($rejectionHandled, p1);

		p2._onRejected = onRejected;
	}

	if (isLongStackTrace) p2._p = p1;
	p1[p1._c++] = p2;

	// 2.2.6
	if (p1._s !== $pending)
		scheduleHandler(p1, p2);

	// 2.2.7
	return p2;
	}

	// iterate tree
	function hashOnRejected (node) {
	// A node shouldn't be checked twice.
	if (node._umark)
		return true;
	else
		node._umark = true;

	var i = 0
		, len = node._c
		, child;

	while (i < len) {
		child = node[i++];
		if (child._onRejected || hashOnRejected(child)) return true;
	}
	}

	function genStackInfo (reason, p) {
	var stackInfo = [];

	function push (trace) {
		return stackInfo.push(trace.replace(/^\s+|\s+$/g, ''));
	}

	if (isLongStackTrace) {
		if (p[$settlerTrace])
			push(p[$settlerTrace]);

		// Hope you guys could understand how the back trace works.
		// We only have to iterate through the tree from the bottom to root.
		(function iter (node) {
			if (node && $promiseTrace in node) {
				iter(node._next);
				push(node[$promiseTrace] + '');
				iter(node._p);
			}
		})(p);
	}

	return (reason && reason.stack ? reason.stack : reason) +
		('\n' + stackInfo.join('\n')).replace($cleanStackReg, '');
	}

	function callHanler (handler, value) {
	// 2.2.5
	return handler(value);
	}

	/**
	* Resolve or reject a promise.
	* @private
	* @param  {Yaku} p
	* @param  {Integer} state
	* @param  {Any} value
	*/
	function settlePromise (p, state, value) {
	var i = 0
		, len = p._c;

	// 2.1.2
	// 2.1.3
	if (p._s === $pending) {
		// 2.1.1.1
		p._s = state;
		p._v = value;

		if (state === $rejected) {
			if (isLongStackTrace && isError(value)) {
				value.longStack = genStackInfo(value, p);
			}

			scheduleUnhandledRejection(p);
		}

		// 2.2.4
		while (i < len) {
			scheduleHandler(p, p[i++]);
		}
	}

	return p;
	}

	/**
	* Resolve or reject promise with value x. The x can also be a thenable.
	* @private
	* @param {Yaku} p
	* @param {Any | Thenable} x A normal value or a thenable.
	*/
	function settleWithX (p, x) {
	// 2.3.1
	if (x === p && x) {
		settlePromise(p, $rejected, genTypeError($promiseCircularChain));
		return p;
	}

	// 2.3.2
	// 2.3.3
	if (x !== $null && (isFunction(x) || isObject(x))) {
		// 2.3.2.1
		var xthen = genTryCatcher(getThen)(x);

		if (xthen === $tryErr) {
			// 2.3.3.2
			settlePromise(p, $rejected, xthen.e);
			return p;
		}

		if (isFunction(xthen)) {
			if (isLongStackTrace && isYaku(x))
				p._next = x;

			// Fix https://bugs.chromium.org/p/v8/issues/detail?id=4162
			if (isYaku(x))
				settleXthen(p, x, xthen);
			else
				Yaku.nextTick(function () {
					settleXthen(p, x, xthen);
				});
		} else
			// 2.3.3.4
			settlePromise(p, $resolved, x);
	} else
		// 2.3.4
		settlePromise(p, $resolved, x);

	return p;
	}

	/**
	* Try to get a promise's then method.
	* @private
	* @param  {Thenable} x
	* @return {Function}
	*/
	function getThen (x) { return x.then; }

	/**
	* Resolve then with its promise.
	* @private
	* @param  {Yaku} p
	* @param  {Thenable} x
	* @param  {Function} xthen
	*/
	function settleXthen (p, x, xthen) {
	// 2.3.3.3
	var err = genTryCatcher(xthen, x)(function (y) {
		// 2.3.3.3.3
		// 2.3.3.3.1
		x && (x = $null, settleWithX(p, y));
	}, function (r) {
		// 2.3.3.3.3
		// 2.3.3.3.2
		x && (x = $null, settlePromise(p, $rejected, r));
	});

	// 2.3.3.3.4.1
	if (err === $tryErr && x) {
		// 2.3.3.3.4.2
		settlePromise(p, $rejected, err.e);
		x = $null;
	}
	}

	root.Promise = Yaku;
})();