973 lines
32 KiB
JavaScript
973 lines
32 KiB
JavaScript
/*!
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* @overview es6-promise - a tiny implementation of Promises/A+.
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* @copyright Copyright (c) 2014 Yehuda Katz, Tom Dale, Stefan Penner and contributors (Conversion to ES6 API by Jake Archibald)
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* @license Licensed under MIT license
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* See https://raw.githubusercontent.com/jakearchibald/es6-promise/master/LICENSE
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* @version 2.3.0
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*/
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(function() {
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"use strict";
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function lib$es6$promise$utils$$objectOrFunction(x) {
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return typeof x === 'function' || (typeof x === 'object' && x !== null);
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}
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function lib$es6$promise$utils$$isFunction(x) {
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return typeof x === 'function';
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}
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function lib$es6$promise$utils$$isMaybeThenable(x) {
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return typeof x === 'object' && x !== null;
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}
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var lib$es6$promise$utils$$_isArray;
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if (!Array.isArray) {
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lib$es6$promise$utils$$_isArray = function (x) {
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return Object.prototype.toString.call(x) === '[object Array]';
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};
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} else {
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lib$es6$promise$utils$$_isArray = Array.isArray;
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}
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var lib$es6$promise$utils$$isArray = lib$es6$promise$utils$$_isArray;
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var lib$es6$promise$asap$$len = 0;
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var lib$es6$promise$asap$$toString = {}.toString;
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var lib$es6$promise$asap$$vertxNext;
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var lib$es6$promise$asap$$customSchedulerFn;
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var lib$es6$promise$asap$$asap = function asap(callback, arg) {
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lib$es6$promise$asap$$queue[lib$es6$promise$asap$$len] = callback;
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lib$es6$promise$asap$$queue[lib$es6$promise$asap$$len + 1] = arg;
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lib$es6$promise$asap$$len += 2;
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if (lib$es6$promise$asap$$len === 2) {
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// If len is 2, that means that we need to schedule an async flush.
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// If additional callbacks are queued before the queue is flushed, they
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// will be processed by this flush that we are scheduling.
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if (lib$es6$promise$asap$$customSchedulerFn) {
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lib$es6$promise$asap$$customSchedulerFn(lib$es6$promise$asap$$flush);
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} else {
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lib$es6$promise$asap$$scheduleFlush();
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}
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}
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}
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function lib$es6$promise$asap$$setScheduler(scheduleFn) {
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lib$es6$promise$asap$$customSchedulerFn = scheduleFn;
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}
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function lib$es6$promise$asap$$setAsap(asapFn) {
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lib$es6$promise$asap$$asap = asapFn;
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}
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var lib$es6$promise$asap$$browserWindow = (typeof window !== 'undefined') ? window : undefined;
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var lib$es6$promise$asap$$browserGlobal = lib$es6$promise$asap$$browserWindow || {};
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var lib$es6$promise$asap$$BrowserMutationObserver = lib$es6$promise$asap$$browserGlobal.MutationObserver || lib$es6$promise$asap$$browserGlobal.WebKitMutationObserver;
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var lib$es6$promise$asap$$isNode = typeof process !== 'undefined' && {}.toString.call(process) === '[object process]';
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// test for web worker but not in IE10
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var lib$es6$promise$asap$$isWorker = typeof Uint8ClampedArray !== 'undefined' &&
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typeof importScripts !== 'undefined' &&
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typeof MessageChannel !== 'undefined';
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// node
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function lib$es6$promise$asap$$useNextTick() {
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var nextTick = process.nextTick;
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// node version 0.10.x displays a deprecation warning when nextTick is used recursively
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// setImmediate should be used instead instead
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var version = process.versions.node.match(/^(?:(\d+)\.)?(?:(\d+)\.)?(\*|\d+)$/);
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if (Array.isArray(version) && version[1] === '0' && version[2] === '10') {
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nextTick = setImmediate;
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}
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return function() {
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nextTick(lib$es6$promise$asap$$flush);
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};
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}
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// vertx
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function lib$es6$promise$asap$$useVertxTimer() {
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return function() {
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lib$es6$promise$asap$$vertxNext(lib$es6$promise$asap$$flush);
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};
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}
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function lib$es6$promise$asap$$useMutationObserver() {
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var iterations = 0;
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var observer = new lib$es6$promise$asap$$BrowserMutationObserver(lib$es6$promise$asap$$flush);
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var node = document.createTextNode('');
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observer.observe(node, { characterData: true });
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return function() {
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node.data = (iterations = ++iterations % 2);
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};
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}
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// web worker
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function lib$es6$promise$asap$$useMessageChannel() {
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var channel = new MessageChannel();
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channel.port1.onmessage = lib$es6$promise$asap$$flush;
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return function () {
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channel.port2.postMessage(0);
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};
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}
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function lib$es6$promise$asap$$useSetTimeout() {
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return function() {
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setTimeout(lib$es6$promise$asap$$flush, 1);
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};
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}
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var lib$es6$promise$asap$$queue = new Array(1000);
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function lib$es6$promise$asap$$flush() {
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for (var i = 0; i < lib$es6$promise$asap$$len; i+=2) {
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var callback = lib$es6$promise$asap$$queue[i];
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var arg = lib$es6$promise$asap$$queue[i+1];
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callback(arg);
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lib$es6$promise$asap$$queue[i] = undefined;
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lib$es6$promise$asap$$queue[i+1] = undefined;
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}
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lib$es6$promise$asap$$len = 0;
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}
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function lib$es6$promise$asap$$attemptVertex() {
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try {
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var r = require;
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var vertx = r('vertx');
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lib$es6$promise$asap$$vertxNext = vertx.runOnLoop || vertx.runOnContext;
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return lib$es6$promise$asap$$useVertxTimer();
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} catch(e) {
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return lib$es6$promise$asap$$useSetTimeout();
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}
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}
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var lib$es6$promise$asap$$scheduleFlush;
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// Decide what async method to use to triggering processing of queued callbacks:
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if (lib$es6$promise$asap$$isNode) {
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lib$es6$promise$asap$$scheduleFlush = lib$es6$promise$asap$$useNextTick();
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} else if (lib$es6$promise$asap$$BrowserMutationObserver) {
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lib$es6$promise$asap$$scheduleFlush = lib$es6$promise$asap$$useMutationObserver();
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} else if (lib$es6$promise$asap$$isWorker) {
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lib$es6$promise$asap$$scheduleFlush = lib$es6$promise$asap$$useMessageChannel();
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} else if (lib$es6$promise$asap$$browserWindow === undefined && typeof require === 'function') {
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lib$es6$promise$asap$$scheduleFlush = lib$es6$promise$asap$$attemptVertex();
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} else {
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lib$es6$promise$asap$$scheduleFlush = lib$es6$promise$asap$$useSetTimeout();
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}
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function lib$es6$promise$$internal$$noop() {}
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var lib$es6$promise$$internal$$PENDING = void 0;
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var lib$es6$promise$$internal$$FULFILLED = 1;
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var lib$es6$promise$$internal$$REJECTED = 2;
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var lib$es6$promise$$internal$$GET_THEN_ERROR = new lib$es6$promise$$internal$$ErrorObject();
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function lib$es6$promise$$internal$$selfFullfillment() {
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return new TypeError("You cannot resolve a promise with itself");
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}
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function lib$es6$promise$$internal$$cannotReturnOwn() {
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return new TypeError('A promises callback cannot return that same promise.');
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}
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function lib$es6$promise$$internal$$getThen(promise) {
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try {
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return promise.then;
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} catch(error) {
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lib$es6$promise$$internal$$GET_THEN_ERROR.error = error;
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return lib$es6$promise$$internal$$GET_THEN_ERROR;
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}
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}
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function lib$es6$promise$$internal$$tryThen(then, value, fulfillmentHandler, rejectionHandler) {
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try {
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then.call(value, fulfillmentHandler, rejectionHandler);
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} catch(e) {
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return e;
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}
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}
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function lib$es6$promise$$internal$$handleForeignThenable(promise, thenable, then) {
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lib$es6$promise$asap$$asap(function(promise) {
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var sealed = false;
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var error = lib$es6$promise$$internal$$tryThen(then, thenable, function(value) {
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if (sealed) { return; }
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sealed = true;
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if (thenable !== value) {
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lib$es6$promise$$internal$$resolve(promise, value);
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} else {
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lib$es6$promise$$internal$$fulfill(promise, value);
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}
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}, function(reason) {
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if (sealed) { return; }
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sealed = true;
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lib$es6$promise$$internal$$reject(promise, reason);
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}, 'Settle: ' + (promise._label || ' unknown promise'));
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if (!sealed && error) {
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sealed = true;
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lib$es6$promise$$internal$$reject(promise, error);
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}
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}, promise);
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}
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function lib$es6$promise$$internal$$handleOwnThenable(promise, thenable) {
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if (thenable._state === lib$es6$promise$$internal$$FULFILLED) {
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lib$es6$promise$$internal$$fulfill(promise, thenable._result);
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} else if (thenable._state === lib$es6$promise$$internal$$REJECTED) {
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lib$es6$promise$$internal$$reject(promise, thenable._result);
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} else {
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lib$es6$promise$$internal$$subscribe(thenable, undefined, function(value) {
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lib$es6$promise$$internal$$resolve(promise, value);
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}, function(reason) {
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lib$es6$promise$$internal$$reject(promise, reason);
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});
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}
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}
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function lib$es6$promise$$internal$$handleMaybeThenable(promise, maybeThenable) {
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if (maybeThenable.constructor === promise.constructor) {
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lib$es6$promise$$internal$$handleOwnThenable(promise, maybeThenable);
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} else {
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var then = lib$es6$promise$$internal$$getThen(maybeThenable);
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if (then === lib$es6$promise$$internal$$GET_THEN_ERROR) {
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lib$es6$promise$$internal$$reject(promise, lib$es6$promise$$internal$$GET_THEN_ERROR.error);
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} else if (then === undefined) {
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lib$es6$promise$$internal$$fulfill(promise, maybeThenable);
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} else if (lib$es6$promise$utils$$isFunction(then)) {
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lib$es6$promise$$internal$$handleForeignThenable(promise, maybeThenable, then);
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} else {
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lib$es6$promise$$internal$$fulfill(promise, maybeThenable);
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}
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}
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}
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function lib$es6$promise$$internal$$resolve(promise, value) {
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if (promise === value) {
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lib$es6$promise$$internal$$reject(promise, lib$es6$promise$$internal$$selfFullfillment());
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} else if (lib$es6$promise$utils$$objectOrFunction(value)) {
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lib$es6$promise$$internal$$handleMaybeThenable(promise, value);
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} else {
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lib$es6$promise$$internal$$fulfill(promise, value);
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}
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}
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function lib$es6$promise$$internal$$publishRejection(promise) {
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if (promise._onerror) {
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promise._onerror(promise._result);
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}
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lib$es6$promise$$internal$$publish(promise);
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}
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function lib$es6$promise$$internal$$fulfill(promise, value) {
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if (promise._state !== lib$es6$promise$$internal$$PENDING) { return; }
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promise._result = value;
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promise._state = lib$es6$promise$$internal$$FULFILLED;
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if (promise._subscribers.length !== 0) {
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lib$es6$promise$asap$$asap(lib$es6$promise$$internal$$publish, promise);
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}
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}
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function lib$es6$promise$$internal$$reject(promise, reason) {
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if (promise._state !== lib$es6$promise$$internal$$PENDING) { return; }
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promise._state = lib$es6$promise$$internal$$REJECTED;
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promise._result = reason;
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lib$es6$promise$asap$$asap(lib$es6$promise$$internal$$publishRejection, promise);
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}
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function lib$es6$promise$$internal$$subscribe(parent, child, onFulfillment, onRejection) {
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var subscribers = parent._subscribers;
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var length = subscribers.length;
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parent._onerror = null;
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subscribers[length] = child;
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subscribers[length + lib$es6$promise$$internal$$FULFILLED] = onFulfillment;
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subscribers[length + lib$es6$promise$$internal$$REJECTED] = onRejection;
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if (length === 0 && parent._state) {
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lib$es6$promise$asap$$asap(lib$es6$promise$$internal$$publish, parent);
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}
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}
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function lib$es6$promise$$internal$$publish(promise) {
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var subscribers = promise._subscribers;
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var settled = promise._state;
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if (subscribers.length === 0) { return; }
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var child, callback, detail = promise._result;
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for (var i = 0; i < subscribers.length; i += 3) {
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child = subscribers[i];
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callback = subscribers[i + settled];
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if (child) {
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lib$es6$promise$$internal$$invokeCallback(settled, child, callback, detail);
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} else {
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callback(detail);
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}
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}
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promise._subscribers.length = 0;
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}
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function lib$es6$promise$$internal$$ErrorObject() {
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this.error = null;
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}
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var lib$es6$promise$$internal$$TRY_CATCH_ERROR = new lib$es6$promise$$internal$$ErrorObject();
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function lib$es6$promise$$internal$$tryCatch(callback, detail) {
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try {
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return callback(detail);
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} catch(e) {
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lib$es6$promise$$internal$$TRY_CATCH_ERROR.error = e;
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return lib$es6$promise$$internal$$TRY_CATCH_ERROR;
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}
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}
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function lib$es6$promise$$internal$$invokeCallback(settled, promise, callback, detail) {
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var hasCallback = lib$es6$promise$utils$$isFunction(callback),
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value, error, succeeded, failed;
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if (hasCallback) {
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value = lib$es6$promise$$internal$$tryCatch(callback, detail);
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if (value === lib$es6$promise$$internal$$TRY_CATCH_ERROR) {
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failed = true;
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error = value.error;
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value = null;
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} else {
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succeeded = true;
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}
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if (promise === value) {
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lib$es6$promise$$internal$$reject(promise, lib$es6$promise$$internal$$cannotReturnOwn());
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return;
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}
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} else {
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value = detail;
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succeeded = true;
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}
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if (promise._state !== lib$es6$promise$$internal$$PENDING) {
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// noop
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} else if (hasCallback && succeeded) {
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lib$es6$promise$$internal$$resolve(promise, value);
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} else if (failed) {
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lib$es6$promise$$internal$$reject(promise, error);
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} else if (settled === lib$es6$promise$$internal$$FULFILLED) {
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lib$es6$promise$$internal$$fulfill(promise, value);
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} else if (settled === lib$es6$promise$$internal$$REJECTED) {
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lib$es6$promise$$internal$$reject(promise, value);
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}
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}
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function lib$es6$promise$$internal$$initializePromise(promise, resolver) {
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try {
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resolver(function resolvePromise(value){
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lib$es6$promise$$internal$$resolve(promise, value);
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}, function rejectPromise(reason) {
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lib$es6$promise$$internal$$reject(promise, reason);
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});
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} catch(e) {
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lib$es6$promise$$internal$$reject(promise, e);
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}
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}
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function lib$es6$promise$enumerator$$Enumerator(Constructor, input) {
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var enumerator = this;
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enumerator._instanceConstructor = Constructor;
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enumerator.promise = new Constructor(lib$es6$promise$$internal$$noop);
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if (enumerator._validateInput(input)) {
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enumerator._input = input;
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enumerator.length = input.length;
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enumerator._remaining = input.length;
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enumerator._init();
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if (enumerator.length === 0) {
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lib$es6$promise$$internal$$fulfill(enumerator.promise, enumerator._result);
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} else {
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enumerator.length = enumerator.length || 0;
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enumerator._enumerate();
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if (enumerator._remaining === 0) {
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lib$es6$promise$$internal$$fulfill(enumerator.promise, enumerator._result);
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}
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}
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} else {
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lib$es6$promise$$internal$$reject(enumerator.promise, enumerator._validationError());
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}
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}
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lib$es6$promise$enumerator$$Enumerator.prototype._validateInput = function(input) {
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return lib$es6$promise$utils$$isArray(input);
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};
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lib$es6$promise$enumerator$$Enumerator.prototype._validationError = function() {
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return new Error('Array Methods must be provided an Array');
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};
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lib$es6$promise$enumerator$$Enumerator.prototype._init = function() {
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this._result = new Array(this.length);
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};
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var lib$es6$promise$enumerator$$default = lib$es6$promise$enumerator$$Enumerator;
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lib$es6$promise$enumerator$$Enumerator.prototype._enumerate = function() {
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var enumerator = this;
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var length = enumerator.length;
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var promise = enumerator.promise;
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var input = enumerator._input;
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for (var i = 0; promise._state === lib$es6$promise$$internal$$PENDING && i < length; i++) {
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enumerator._eachEntry(input[i], i);
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}
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};
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lib$es6$promise$enumerator$$Enumerator.prototype._eachEntry = function(entry, i) {
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var enumerator = this;
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var c = enumerator._instanceConstructor;
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|
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if (lib$es6$promise$utils$$isMaybeThenable(entry)) {
|
|
if (entry.constructor === c && entry._state !== lib$es6$promise$$internal$$PENDING) {
|
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entry._onerror = null;
|
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enumerator._settledAt(entry._state, i, entry._result);
|
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} else {
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enumerator._willSettleAt(c.resolve(entry), i);
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}
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} else {
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enumerator._remaining--;
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enumerator._result[i] = entry;
|
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}
|
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};
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|
|
lib$es6$promise$enumerator$$Enumerator.prototype._settledAt = function(state, i, value) {
|
|
var enumerator = this;
|
|
var promise = enumerator.promise;
|
|
|
|
if (promise._state === lib$es6$promise$$internal$$PENDING) {
|
|
enumerator._remaining--;
|
|
|
|
if (state === lib$es6$promise$$internal$$REJECTED) {
|
|
lib$es6$promise$$internal$$reject(promise, value);
|
|
} else {
|
|
enumerator._result[i] = value;
|
|
}
|
|
}
|
|
|
|
if (enumerator._remaining === 0) {
|
|
lib$es6$promise$$internal$$fulfill(promise, enumerator._result);
|
|
}
|
|
};
|
|
|
|
lib$es6$promise$enumerator$$Enumerator.prototype._willSettleAt = function(promise, i) {
|
|
var enumerator = this;
|
|
|
|
lib$es6$promise$$internal$$subscribe(promise, undefined, function(value) {
|
|
enumerator._settledAt(lib$es6$promise$$internal$$FULFILLED, i, value);
|
|
}, function(reason) {
|
|
enumerator._settledAt(lib$es6$promise$$internal$$REJECTED, i, reason);
|
|
});
|
|
};
|
|
function lib$es6$promise$promise$all$$all(entries) {
|
|
return new lib$es6$promise$enumerator$$default(this, entries).promise;
|
|
}
|
|
var lib$es6$promise$promise$all$$default = lib$es6$promise$promise$all$$all;
|
|
function lib$es6$promise$promise$race$$race(entries) {
|
|
/*jshint validthis:true */
|
|
var Constructor = this;
|
|
|
|
var promise = new Constructor(lib$es6$promise$$internal$$noop);
|
|
|
|
if (!lib$es6$promise$utils$$isArray(entries)) {
|
|
lib$es6$promise$$internal$$reject(promise, new TypeError('You must pass an array to race.'));
|
|
return promise;
|
|
}
|
|
|
|
var length = entries.length;
|
|
|
|
function onFulfillment(value) {
|
|
lib$es6$promise$$internal$$resolve(promise, value);
|
|
}
|
|
|
|
function onRejection(reason) {
|
|
lib$es6$promise$$internal$$reject(promise, reason);
|
|
}
|
|
|
|
for (var i = 0; promise._state === lib$es6$promise$$internal$$PENDING && i < length; i++) {
|
|
lib$es6$promise$$internal$$subscribe(Constructor.resolve(entries[i]), undefined, onFulfillment, onRejection);
|
|
}
|
|
|
|
return promise;
|
|
}
|
|
var lib$es6$promise$promise$race$$default = lib$es6$promise$promise$race$$race;
|
|
function lib$es6$promise$promise$resolve$$resolve(object) {
|
|
/*jshint validthis:true */
|
|
var Constructor = this;
|
|
|
|
if (object && typeof object === 'object' && object.constructor === Constructor) {
|
|
return object;
|
|
}
|
|
|
|
var promise = new Constructor(lib$es6$promise$$internal$$noop);
|
|
lib$es6$promise$$internal$$resolve(promise, object);
|
|
return promise;
|
|
}
|
|
var lib$es6$promise$promise$resolve$$default = lib$es6$promise$promise$resolve$$resolve;
|
|
function lib$es6$promise$promise$reject$$reject(reason) {
|
|
/*jshint validthis:true */
|
|
var Constructor = this;
|
|
var promise = new Constructor(lib$es6$promise$$internal$$noop);
|
|
lib$es6$promise$$internal$$reject(promise, reason);
|
|
return promise;
|
|
}
|
|
var lib$es6$promise$promise$reject$$default = lib$es6$promise$promise$reject$$reject;
|
|
|
|
var lib$es6$promise$promise$$counter = 0;
|
|
|
|
function lib$es6$promise$promise$$needsResolver() {
|
|
throw new TypeError('You must pass a resolver function as the first argument to the promise constructor');
|
|
}
|
|
|
|
function lib$es6$promise$promise$$needsNew() {
|
|
throw new TypeError("Failed to construct 'Promise': Please use the 'new' operator, this object constructor cannot be called as a function.");
|
|
}
|
|
|
|
var lib$es6$promise$promise$$default = lib$es6$promise$promise$$Promise;
|
|
/**
|
|
Promise objects represent the eventual result of an asynchronous operation. The
|
|
primary way of interacting with a promise is through its `then` method, which
|
|
registers callbacks to receive either a promise's eventual value or the reason
|
|
why the promise cannot be fulfilled.
|
|
|
|
Terminology
|
|
-----------
|
|
|
|
- `promise` is an object or function with a `then` method whose behavior conforms to this specification.
|
|
- `thenable` is an object or function that defines a `then` method.
|
|
- `value` is any legal JavaScript value (including undefined, a thenable, or a promise).
|
|
- `exception` is a value that is thrown using the throw statement.
|
|
- `reason` is a value that indicates why a promise was rejected.
|
|
- `settled` the final resting state of a promise, fulfilled or rejected.
|
|
|
|
A promise can be in one of three states: pending, fulfilled, or rejected.
|
|
|
|
Promises that are fulfilled have a fulfillment value and are in the fulfilled
|
|
state. Promises that are rejected have a rejection reason and are in the
|
|
rejected state. A fulfillment value is never a thenable.
|
|
|
|
Promises can also be said to *resolve* a value. If this value is also a
|
|
promise, then the original promise's settled state will match the value's
|
|
settled state. So a promise that *resolves* a promise that rejects will
|
|
itself reject, and a promise that *resolves* a promise that fulfills will
|
|
itself fulfill.
|
|
|
|
|
|
Basic Usage:
|
|
------------
|
|
|
|
```js
|
|
var promise = new Promise(function(resolve, reject) {
|
|
// on success
|
|
resolve(value);
|
|
|
|
// on failure
|
|
reject(reason);
|
|
});
|
|
|
|
promise.then(function(value) {
|
|
// on fulfillment
|
|
}, function(reason) {
|
|
// on rejection
|
|
});
|
|
```
|
|
|
|
Advanced Usage:
|
|
---------------
|
|
|
|
Promises shine when abstracting away asynchronous interactions such as
|
|
`XMLHttpRequest`s.
|
|
|
|
```js
|
|
function getJSON(url) {
|
|
return new Promise(function(resolve, reject){
|
|
var xhr = new XMLHttpRequest();
|
|
|
|
xhr.open('GET', url);
|
|
xhr.onreadystatechange = handler;
|
|
xhr.responseType = 'json';
|
|
xhr.setRequestHeader('Accept', 'application/json');
|
|
xhr.send();
|
|
|
|
function handler() {
|
|
if (this.readyState === this.DONE) {
|
|
if (this.status === 200) {
|
|
resolve(this.response);
|
|
} else {
|
|
reject(new Error('getJSON: `' + url + '` failed with status: [' + this.status + ']'));
|
|
}
|
|
}
|
|
};
|
|
});
|
|
}
|
|
|
|
getJSON('/posts.json').then(function(json) {
|
|
// on fulfillment
|
|
}, function(reason) {
|
|
// on rejection
|
|
});
|
|
```
|
|
|
|
Unlike callbacks, promises are great composable primitives.
|
|
|
|
```js
|
|
Promise.all([
|
|
getJSON('/posts'),
|
|
getJSON('/comments')
|
|
]).then(function(values){
|
|
values[0] // => postsJSON
|
|
values[1] // => commentsJSON
|
|
|
|
return values;
|
|
});
|
|
```
|
|
|
|
@class Promise
|
|
@param {function} resolver
|
|
Useful for tooling.
|
|
@constructor
|
|
*/
|
|
function lib$es6$promise$promise$$Promise(resolver) {
|
|
this._id = lib$es6$promise$promise$$counter++;
|
|
this._state = undefined;
|
|
this._result = undefined;
|
|
this._subscribers = [];
|
|
|
|
if (lib$es6$promise$$internal$$noop !== resolver) {
|
|
if (!lib$es6$promise$utils$$isFunction(resolver)) {
|
|
lib$es6$promise$promise$$needsResolver();
|
|
}
|
|
|
|
if (!(this instanceof lib$es6$promise$promise$$Promise)) {
|
|
lib$es6$promise$promise$$needsNew();
|
|
}
|
|
|
|
lib$es6$promise$$internal$$initializePromise(this, resolver);
|
|
}
|
|
}
|
|
|
|
lib$es6$promise$promise$$Promise.all = lib$es6$promise$promise$all$$default;
|
|
lib$es6$promise$promise$$Promise.race = lib$es6$promise$promise$race$$default;
|
|
lib$es6$promise$promise$$Promise.resolve = lib$es6$promise$promise$resolve$$default;
|
|
lib$es6$promise$promise$$Promise.reject = lib$es6$promise$promise$reject$$default;
|
|
lib$es6$promise$promise$$Promise._setScheduler = lib$es6$promise$asap$$setScheduler;
|
|
lib$es6$promise$promise$$Promise._setAsap = lib$es6$promise$asap$$setAsap;
|
|
lib$es6$promise$promise$$Promise._asap = lib$es6$promise$asap$$asap;
|
|
|
|
lib$es6$promise$promise$$Promise.prototype = {
|
|
constructor: lib$es6$promise$promise$$Promise,
|
|
|
|
/**
|
|
The primary way of interacting with a promise is through its `then` method,
|
|
which registers callbacks to receive either a promise's eventual value or the
|
|
reason why the promise cannot be fulfilled.
|
|
|
|
```js
|
|
findUser().then(function(user){
|
|
// user is available
|
|
}, function(reason){
|
|
// user is unavailable, and you are given the reason why
|
|
});
|
|
```
|
|
|
|
Chaining
|
|
--------
|
|
|
|
The return value of `then` is itself a promise. This second, 'downstream'
|
|
promise is resolved with the return value of the first promise's fulfillment
|
|
or rejection handler, or rejected if the handler throws an exception.
|
|
|
|
```js
|
|
findUser().then(function (user) {
|
|
return user.name;
|
|
}, function (reason) {
|
|
return 'default name';
|
|
}).then(function (userName) {
|
|
// If `findUser` fulfilled, `userName` will be the user's name, otherwise it
|
|
// will be `'default name'`
|
|
});
|
|
|
|
findUser().then(function (user) {
|
|
throw new Error('Found user, but still unhappy');
|
|
}, function (reason) {
|
|
throw new Error('`findUser` rejected and we're unhappy');
|
|
}).then(function (value) {
|
|
// never reached
|
|
}, function (reason) {
|
|
// if `findUser` fulfilled, `reason` will be 'Found user, but still unhappy'.
|
|
// If `findUser` rejected, `reason` will be '`findUser` rejected and we're unhappy'.
|
|
});
|
|
```
|
|
If the downstream promise does not specify a rejection handler, rejection reasons will be propagated further downstream.
|
|
|
|
```js
|
|
findUser().then(function (user) {
|
|
throw new PedagogicalException('Upstream error');
|
|
}).then(function (value) {
|
|
// never reached
|
|
}).then(function (value) {
|
|
// never reached
|
|
}, function (reason) {
|
|
// The `PedgagocialException` is propagated all the way down to here
|
|
});
|
|
```
|
|
|
|
Assimilation
|
|
------------
|
|
|
|
Sometimes the value you want to propagate to a downstream promise can only be
|
|
retrieved asynchronously. This can be achieved by returning a promise in the
|
|
fulfillment or rejection handler. The downstream promise will then be pending
|
|
until the returned promise is settled. This is called *assimilation*.
|
|
|
|
```js
|
|
findUser().then(function (user) {
|
|
return findCommentsByAuthor(user);
|
|
}).then(function (comments) {
|
|
// The user's comments are now available
|
|
});
|
|
```
|
|
|
|
If the assimliated promise rejects, then the downstream promise will also reject.
|
|
|
|
```js
|
|
findUser().then(function (user) {
|
|
return findCommentsByAuthor(user);
|
|
}).then(function (comments) {
|
|
// If `findCommentsByAuthor` fulfills, we'll have the value here
|
|
}, function (reason) {
|
|
// If `findCommentsByAuthor` rejects, we'll have the reason here
|
|
});
|
|
```
|
|
|
|
Simple Example
|
|
--------------
|
|
|
|
Synchronous Example
|
|
|
|
```javascript
|
|
var result;
|
|
|
|
try {
|
|
result = findResult();
|
|
// success
|
|
} catch(reason) {
|
|
// failure
|
|
}
|
|
```
|
|
|
|
Errback Example
|
|
|
|
```js
|
|
findResult(function(result, err){
|
|
if (err) {
|
|
// failure
|
|
} else {
|
|
// success
|
|
}
|
|
});
|
|
```
|
|
|
|
Promise Example;
|
|
|
|
```javascript
|
|
findResult().then(function(result){
|
|
// success
|
|
}, function(reason){
|
|
// failure
|
|
});
|
|
```
|
|
|
|
Advanced Example
|
|
--------------
|
|
|
|
Synchronous Example
|
|
|
|
```javascript
|
|
var author, books;
|
|
|
|
try {
|
|
author = findAuthor();
|
|
books = findBooksByAuthor(author);
|
|
// success
|
|
} catch(reason) {
|
|
// failure
|
|
}
|
|
```
|
|
|
|
Errback Example
|
|
|
|
```js
|
|
|
|
function foundBooks(books) {
|
|
|
|
}
|
|
|
|
function failure(reason) {
|
|
|
|
}
|
|
|
|
findAuthor(function(author, err){
|
|
if (err) {
|
|
failure(err);
|
|
// failure
|
|
} else {
|
|
try {
|
|
findBoooksByAuthor(author, function(books, err) {
|
|
if (err) {
|
|
failure(err);
|
|
} else {
|
|
try {
|
|
foundBooks(books);
|
|
} catch(reason) {
|
|
failure(reason);
|
|
}
|
|
}
|
|
});
|
|
} catch(error) {
|
|
failure(err);
|
|
}
|
|
// success
|
|
}
|
|
});
|
|
```
|
|
|
|
Promise Example;
|
|
|
|
```javascript
|
|
findAuthor().
|
|
then(findBooksByAuthor).
|
|
then(function(books){
|
|
// found books
|
|
}).catch(function(reason){
|
|
// something went wrong
|
|
});
|
|
```
|
|
|
|
@method then
|
|
@param {Function} onFulfilled
|
|
@param {Function} onRejected
|
|
Useful for tooling.
|
|
@return {Promise}
|
|
*/
|
|
then: function(onFulfillment, onRejection) {
|
|
var parent = this;
|
|
var state = parent._state;
|
|
|
|
if (state === lib$es6$promise$$internal$$FULFILLED && !onFulfillment || state === lib$es6$promise$$internal$$REJECTED && !onRejection) {
|
|
return this;
|
|
}
|
|
|
|
var child = new this.constructor(lib$es6$promise$$internal$$noop);
|
|
var result = parent._result;
|
|
|
|
if (state) {
|
|
var callback = arguments[state - 1];
|
|
lib$es6$promise$asap$$asap(function(){
|
|
lib$es6$promise$$internal$$invokeCallback(state, child, callback, result);
|
|
});
|
|
} else {
|
|
lib$es6$promise$$internal$$subscribe(parent, child, onFulfillment, onRejection);
|
|
}
|
|
|
|
return child;
|
|
},
|
|
|
|
/**
|
|
`catch` is simply sugar for `then(undefined, onRejection)` which makes it the same
|
|
as the catch block of a try/catch statement.
|
|
|
|
```js
|
|
function findAuthor(){
|
|
throw new Error('couldn't find that author');
|
|
}
|
|
|
|
// synchronous
|
|
try {
|
|
findAuthor();
|
|
} catch(reason) {
|
|
// something went wrong
|
|
}
|
|
|
|
// async with promises
|
|
findAuthor().catch(function(reason){
|
|
// something went wrong
|
|
});
|
|
```
|
|
|
|
@method catch
|
|
@param {Function} onRejection
|
|
Useful for tooling.
|
|
@return {Promise}
|
|
*/
|
|
'catch': function(onRejection) {
|
|
return this.then(null, onRejection);
|
|
}
|
|
};
|
|
function lib$es6$promise$polyfill$$polyfill() {
|
|
var local;
|
|
|
|
if (typeof global !== 'undefined') {
|
|
local = global;
|
|
} else if (typeof self !== 'undefined') {
|
|
local = self;
|
|
} else {
|
|
try {
|
|
local = Function('return this')();
|
|
} catch (e) {
|
|
throw new Error('polyfill failed because global object is unavailable in this environment');
|
|
}
|
|
}
|
|
|
|
var P = local.Promise;
|
|
|
|
if (P && Object.prototype.toString.call(P.resolve()) === '[object Promise]' && !P.cast) {
|
|
return;
|
|
}
|
|
|
|
local.Promise = lib$es6$promise$promise$$default;
|
|
}
|
|
var lib$es6$promise$polyfill$$default = lib$es6$promise$polyfill$$polyfill;
|
|
|
|
var lib$es6$promise$umd$$ES6Promise = {
|
|
'Promise': lib$es6$promise$promise$$default,
|
|
'polyfill': lib$es6$promise$polyfill$$default
|
|
};
|
|
|
|
/* global define:true module:true window: true */
|
|
if (typeof define === 'function' && define['amd']) {
|
|
define(function() { return lib$es6$promise$umd$$ES6Promise; });
|
|
} else if (typeof module !== 'undefined' && module['exports']) {
|
|
module['exports'] = lib$es6$promise$umd$$ES6Promise;
|
|
} else if (typeof this !== 'undefined') {
|
|
this['ES6Promise'] = lib$es6$promise$umd$$ES6Promise;
|
|
}
|
|
|
|
lib$es6$promise$polyfill$$default();
|
|
}).call(this);
|
|
|