forked from mixi-inc/JavaScriptTraining
-
Notifications
You must be signed in to change notification settings - Fork 1
Expand file tree
/
Copy pathq.js
More file actions
2048 lines (1823 loc) · 61.3 KB
/
q.js
File metadata and controls
2048 lines (1823 loc) · 61.3 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// vim:ts=4:sts=4:sw=4:
/*!
*
* Copyright 2009-2012 Kris Kowal under the terms of the MIT
* license found at http://github.com/kriskowal/q/raw/master/LICENSE
*
* With parts by Tyler Close
* Copyright 2007-2009 Tyler Close under the terms of the MIT X license found
* at http://www.opensource.org/licenses/mit-license.html
* Forked at ref_send.js version: 2009-05-11
*
* With parts by Mark Miller
* Copyright (C) 2011 Google Inc.
*
* 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.
*
*/
(function (definition) {
"use strict";
// This file will function properly as a <script> tag, or a module
// using CommonJS and NodeJS or RequireJS module formats. In
// Common/Node/RequireJS, the module exports the Q API and when
// executed as a simple <script>, it creates a Q global instead.
// Montage Require
if (typeof bootstrap === "function") {
bootstrap("promise", definition);
// CommonJS
} else if (typeof exports === "object" && typeof module === "object") {
module.exports = definition();
// RequireJS
} else if (typeof define === "function" && define.amd) {
define(definition);
// SES (Secure EcmaScript)
} else if (typeof ses !== "undefined") {
if (!ses.ok()) {
return;
} else {
ses.makeQ = definition;
}
// <script>
} else if (typeof window !== "undefined" || typeof self !== "undefined") {
// Prefer window over self for add-on scripts. Use self for
// non-windowed contexts.
var global = typeof window !== "undefined" ? window : self;
// Get the `window` object, save the previous Q global
// and initialize Q as a global.
var previousQ = global.Q;
global.Q = definition();
// Add a noConflict function so Q can be removed from the
// global namespace.
global.Q.noConflict = function () {
global.Q = previousQ;
return this;
};
} else {
throw new Error("This environment was not anticipated by Q. Please file a bug.");
}
})(function () {
"use strict";
var hasStacks = false;
try {
throw new Error();
} catch (e) {
hasStacks = !!e.stack;
}
// All code after this point will be filtered from stack traces reported
// by Q.
var qStartingLine = captureLine();
var qFileName;
// shims
// used for fallback in "allResolved"
var noop = function () {};
// Use the fastest possible means to execute a task in a future turn
// of the event loop.
var nextTick =(function () {
// linked list of tasks (single, with head node)
var head = {task: void 0, next: null};
var tail = head;
var flushing = false;
var requestTick = void 0;
var isNodeJS = false;
// queue for late tasks, used by unhandled rejection tracking
var laterQueue = [];
function flush() {
/* jshint loopfunc: true */
var task, domain;
while (head.next) {
head = head.next;
task = head.task;
head.task = void 0;
domain = head.domain;
if (domain) {
head.domain = void 0;
domain.enter();
}
runSingle(task, domain);
}
while (laterQueue.length) {
task = laterQueue.pop();
runSingle(task);
}
flushing = false;
}
// runs a single function in the async queue
function runSingle(task, domain) {
try {
task();
} catch (e) {
if (isNodeJS) {
// In node, uncaught exceptions are considered fatal errors.
// Re-throw them synchronously to interrupt flushing!
// Ensure continuation if the uncaught exception is suppressed
// listening "uncaughtException" events (as domains does).
// Continue in next event to avoid tick recursion.
if (domain) {
domain.exit();
}
setTimeout(flush, 0);
if (domain) {
domain.enter();
}
throw e;
} else {
// In browsers, uncaught exceptions are not fatal.
// Re-throw them asynchronously to avoid slow-downs.
setTimeout(function () {
throw e;
}, 0);
}
}
if (domain) {
domain.exit();
}
}
nextTick = function (task) {
tail = tail.next = {
task: task,
domain: isNodeJS && process.domain,
next: null
};
if (!flushing) {
flushing = true;
requestTick();
}
};
if (typeof process === "object" &&
process.toString() === "[object process]" && process.nextTick) {
// Ensure Q is in a real Node environment, with a `process.nextTick`.
// To see through fake Node environments:
// * Mocha test runner - exposes a `process` global without a `nextTick`
// * Browserify - exposes a `process.nexTick` function that uses
// `setTimeout`. In this case `setImmediate` is preferred because
// it is faster. Browserify's `process.toString()` yields
// "[object Object]", while in a real Node environment
// `process.nextTick()` yields "[object process]".
isNodeJS = true;
requestTick = function () {
process.nextTick(flush);
};
} else if (typeof setImmediate === "function") {
// In IE10, Node.js 0.9+, or https://github.com/NobleJS/setImmediate
if (typeof window !== "undefined") {
requestTick = setImmediate.bind(window, flush);
} else {
requestTick = function () {
setImmediate(flush);
};
}
} else if (typeof MessageChannel !== "undefined") {
// modern browsers
// http://www.nonblocking.io/2011/06/windownexttick.html
var channel = new MessageChannel();
// At least Safari Version 6.0.5 (8536.30.1) intermittently cannot create
// working message ports the first time a page loads.
channel.port1.onmessage = function () {
requestTick = requestPortTick;
channel.port1.onmessage = flush;
flush();
};
var requestPortTick = function () {
// Opera requires us to provide a message payload, regardless of
// whether we use it.
channel.port2.postMessage(0);
};
requestTick = function () {
setTimeout(flush, 0);
requestPortTick();
};
} else {
// old browsers
requestTick = function () {
setTimeout(flush, 0);
};
}
// runs a task after all other tasks have been run
// this is useful for unhandled rejection tracking that needs to happen
// after all `then`d tasks have been run.
nextTick.runAfter = function (task) {
laterQueue.push(task);
if (!flushing) {
flushing = true;
requestTick();
}
};
return nextTick;
})();
// Attempt to make generics safe in the face of downstream
// modifications.
// There is no situation where this is necessary.
// If you need a security guarantee, these primordials need to be
// deeply frozen anyway, and if you don’t need a security guarantee,
// this is just plain paranoid.
// However, this **might** have the nice side-effect of reducing the size of
// the minified code by reducing x.call() to merely x()
// See Mark Miller’s explanation of what this does.
// http://wiki.ecmascript.org/doku.php?id=conventions:safe_meta_programming
var call = Function.call;
function uncurryThis(f) {
return function () {
return call.apply(f, arguments);
};
}
// This is equivalent, but slower:
// uncurryThis = Function_bind.bind(Function_bind.call);
// http://jsperf.com/uncurrythis
var array_slice = uncurryThis(Array.prototype.slice);
var array_reduce = uncurryThis(
Array.prototype.reduce || function (callback, basis) {
var index = 0,
length = this.length;
// concerning the initial value, if one is not provided
if (arguments.length === 1) {
// seek to the first value in the array, accounting
// for the possibility that is is a sparse array
do {
if (index in this) {
basis = this[index++];
break;
}
if (++index >= length) {
throw new TypeError();
}
} while (1);
}
// reduce
for (; index < length; index++) {
// account for the possibility that the array is sparse
if (index in this) {
basis = callback(basis, this[index], index);
}
}
return basis;
}
);
var array_indexOf = uncurryThis(
Array.prototype.indexOf || function (value) {
// not a very good shim, but good enough for our one use of it
for (var i = 0; i < this.length; i++) {
if (this[i] === value) {
return i;
}
}
return -1;
}
);
var array_map = uncurryThis(
Array.prototype.map || function (callback, thisp) {
var self = this;
var collect = [];
array_reduce(self, function (undefined, value, index) {
collect.push(callback.call(thisp, value, index, self));
}, void 0);
return collect;
}
);
var object_create = Object.create || function (prototype) {
function Type() { }
Type.prototype = prototype;
return new Type();
};
var object_hasOwnProperty = uncurryThis(Object.prototype.hasOwnProperty);
var object_keys = Object.keys || function (object) {
var keys = [];
for (var key in object) {
if (object_hasOwnProperty(object, key)) {
keys.push(key);
}
}
return keys;
};
var object_toString = uncurryThis(Object.prototype.toString);
function isObject(value) {
return value === Object(value);
}
// generator related shims
// FIXME: Remove this function once ES6 generators are in SpiderMonkey.
function isStopIteration(exception) {
return (
object_toString(exception) === "[object StopIteration]" ||
exception instanceof QReturnValue
);
}
// FIXME: Remove this helper and Q.return once ES6 generators are in
// SpiderMonkey.
var QReturnValue;
if (typeof ReturnValue !== "undefined") {
QReturnValue = ReturnValue;
} else {
QReturnValue = function (value) {
this.value = value;
};
}
// long stack traces
var STACK_JUMP_SEPARATOR = "From previous event:";
function makeStackTraceLong(error, promise) {
// If possible, transform the error stack trace by removing Node and Q
// cruft, then concatenating with the stack trace of `promise`. See #57.
if (hasStacks &&
promise.stack &&
typeof error === "object" &&
error !== null &&
error.stack &&
error.stack.indexOf(STACK_JUMP_SEPARATOR) === -1
) {
var stacks = [];
for (var p = promise; !!p; p = p.source) {
if (p.stack) {
stacks.unshift(p.stack);
}
}
stacks.unshift(error.stack);
var concatedStacks = stacks.join("\n" + STACK_JUMP_SEPARATOR + "\n");
error.stack = filterStackString(concatedStacks);
}
}
function filterStackString(stackString) {
var lines = stackString.split("\n");
var desiredLines = [];
for (var i = 0; i < lines.length; ++i) {
var line = lines[i];
if (!isInternalFrame(line) && !isNodeFrame(line) && line) {
desiredLines.push(line);
}
}
return desiredLines.join("\n");
}
function isNodeFrame(stackLine) {
return stackLine.indexOf("(module.js:") !== -1 ||
stackLine.indexOf("(node.js:") !== -1;
}
function getFileNameAndLineNumber(stackLine) {
// Named functions: "at functionName (filename:lineNumber:columnNumber)"
// In IE10 function name can have spaces ("Anonymous function") O_o
var attempt1 = /at .+ \((.+):(\d+):(?:\d+)\)$/.exec(stackLine);
if (attempt1) {
return [attempt1[1], Number(attempt1[2])];
}
// Anonymous functions: "at filename:lineNumber:columnNumber"
var attempt2 = /at ([^ ]+):(\d+):(?:\d+)$/.exec(stackLine);
if (attempt2) {
return [attempt2[1], Number(attempt2[2])];
}
// Firefox style: "function@filename:lineNumber or @filename:lineNumber"
var attempt3 = /.*@(.+):(\d+)$/.exec(stackLine);
if (attempt3) {
return [attempt3[1], Number(attempt3[2])];
}
}
function isInternalFrame(stackLine) {
var fileNameAndLineNumber = getFileNameAndLineNumber(stackLine);
if (!fileNameAndLineNumber) {
return false;
}
var fileName = fileNameAndLineNumber[0];
var lineNumber = fileNameAndLineNumber[1];
return fileName === qFileName &&
lineNumber >= qStartingLine &&
lineNumber <= qEndingLine;
}
// discover own file name and line number range for filtering stack
// traces
function captureLine() {
if (!hasStacks) {
return;
}
try {
throw new Error();
} catch (e) {
var lines = e.stack.split("\n");
var firstLine = lines[0].indexOf("@") > 0 ? lines[1] : lines[2];
var fileNameAndLineNumber = getFileNameAndLineNumber(firstLine);
if (!fileNameAndLineNumber) {
return;
}
qFileName = fileNameAndLineNumber[0];
return fileNameAndLineNumber[1];
}
}
function deprecate(callback, name, alternative) {
return function () {
if (typeof console !== "undefined" &&
typeof console.warn === "function") {
console.warn(name + " is deprecated, use " + alternative +
" instead.", new Error("").stack);
}
return callback.apply(callback, arguments);
};
}
// end of shims
// beginning of real work
/**
* Constructs a promise for an immediate reference, passes promises through, or
* coerces promises from different systems.
* @param value immediate reference or promise
*/
function Q(value) {
// If the object is already a Promise, return it directly. This enables
// the resolve function to both be used to created references from objects,
// but to tolerably coerce non-promises to promises.
if (value instanceof Promise) {
return value;
}
// assimilate thenables
if (isPromiseAlike(value)) {
return coerce(value);
} else {
return fulfill(value);
}
}
Q.resolve = Q;
/**
* Performs a task in a future turn of the event loop.
* @param {Function} task
*/
Q.nextTick = nextTick;
/**
* Controls whether or not long stack traces will be on
*/
Q.longStackSupport = false;
// enable long stacks if Q_DEBUG is set
if (typeof process === "object" && process && process.env && process.env.Q_DEBUG) {
Q.longStackSupport = true;
}
/**
* Constructs a {promise, resolve, reject} object.
*
* `resolve` is a callback to invoke with a more resolved value for the
* promise. To fulfill the promise, invoke `resolve` with any value that is
* not a thenable. To reject the promise, invoke `resolve` with a rejected
* thenable, or invoke `reject` with the reason directly. To resolve the
* promise to another thenable, thus putting it in the same state, invoke
* `resolve` with that other thenable.
*/
Q.defer = defer;
function defer() {
// if "messages" is an "Array", that indicates that the promise has not yet
// been resolved. If it is "undefined", it has been resolved. Each
// element of the messages array is itself an array of complete arguments to
// forward to the resolved promise. We coerce the resolution value to a
// promise using the `resolve` function because it handles both fully
// non-thenable values and other thenables gracefully.
var messages = [], progressListeners = [], resolvedPromise;
var deferred = object_create(defer.prototype);
var promise = object_create(Promise.prototype);
promise.promiseDispatch = function (resolve, op, operands) {
var args = array_slice(arguments);
if (messages) {
messages.push(args);
if (op === "when" && operands[1]) { // progress operand
progressListeners.push(operands[1]);
}
} else {
Q.nextTick(function () {
resolvedPromise.promiseDispatch.apply(resolvedPromise, args);
});
}
};
// XXX deprecated
promise.valueOf = function () {
if (messages) {
return promise;
}
var nearerValue = nearer(resolvedPromise);
if (isPromise(nearerValue)) {
resolvedPromise = nearerValue; // shorten chain
}
return nearerValue;
};
promise.inspect = function () {
if (!resolvedPromise) {
return { state: "pending" };
}
return resolvedPromise.inspect();
};
if (Q.longStackSupport && hasStacks) {
try {
throw new Error();
} catch (e) {
// NOTE: don't try to use `Error.captureStackTrace` or transfer the
// accessor around; that causes memory leaks as per GH-111. Just
// reify the stack trace as a string ASAP.
//
// At the same time, cut off the first line; it's always just
// "[object Promise]\n", as per the `toString`.
promise.stack = e.stack.substring(e.stack.indexOf("\n") + 1);
}
}
// NOTE: we do the checks for `resolvedPromise` in each method, instead of
// consolidating them into `become`, since otherwise we'd create new
// promises with the lines `become(whatever(value))`. See e.g. GH-252.
function become(newPromise) {
resolvedPromise = newPromise;
promise.source = newPromise;
array_reduce(messages, function (undefined, message) {
Q.nextTick(function () {
newPromise.promiseDispatch.apply(newPromise, message);
});
}, void 0);
messages = void 0;
progressListeners = void 0;
}
deferred.promise = promise;
deferred.resolve = function (value) {
if (resolvedPromise) {
return;
}
become(Q(value));
};
deferred.fulfill = function (value) {
if (resolvedPromise) {
return;
}
become(fulfill(value));
};
deferred.reject = function (reason) {
if (resolvedPromise) {
return;
}
become(reject(reason));
};
deferred.notify = function (progress) {
if (resolvedPromise) {
return;
}
array_reduce(progressListeners, function (undefined, progressListener) {
Q.nextTick(function () {
progressListener(progress);
});
}, void 0);
};
return deferred;
}
/**
* Creates a Node-style callback that will resolve or reject the deferred
* promise.
* @returns a nodeback
*/
defer.prototype.makeNodeResolver = function () {
var self = this;
return function (error, value) {
if (error) {
self.reject(error);
} else if (arguments.length > 2) {
self.resolve(array_slice(arguments, 1));
} else {
self.resolve(value);
}
};
};
/**
* @param resolver {Function} a function that returns nothing and accepts
* the resolve, reject, and notify functions for a deferred.
* @returns a promise that may be resolved with the given resolve and reject
* functions, or rejected by a thrown exception in resolver
*/
Q.Promise = promise; // ES6
Q.promise = promise;
function promise(resolver) {
if (typeof resolver !== "function") {
throw new TypeError("resolver must be a function.");
}
var deferred = defer();
try {
resolver(deferred.resolve, deferred.reject, deferred.notify);
} catch (reason) {
deferred.reject(reason);
}
return deferred.promise;
}
promise.race = race; // ES6
promise.all = all; // ES6
promise.reject = reject; // ES6
promise.resolve = Q; // ES6
// XXX experimental. This method is a way to denote that a local value is
// serializable and should be immediately dispatched to a remote upon request,
// instead of passing a reference.
Q.passByCopy = function (object) {
//freeze(object);
//passByCopies.set(object, true);
return object;
};
Promise.prototype.passByCopy = function () {
//freeze(object);
//passByCopies.set(object, true);
return this;
};
/**
* If two promises eventually fulfill to the same value, promises that value,
* but otherwise rejects.
* @param x {Any*}
* @param y {Any*}
* @returns {Any*} a promise for x and y if they are the same, but a rejection
* otherwise.
*
*/
Q.join = function (x, y) {
return Q(x).join(y);
};
Promise.prototype.join = function (that) {
return Q([this, that]).spread(function (x, y) {
if (x === y) {
// TODO: "===" should be Object.is or equiv
return x;
} else {
throw new Error("Can't join: not the same: " + x + " " + y);
}
});
};
/**
* Returns a promise for the first of an array of promises to become settled.
* @param answers {Array[Any*]} promises to race
* @returns {Any*} the first promise to be settled
*/
Q.race = race;
function race(answerPs) {
return promise(function (resolve, reject) {
// Switch to this once we can assume at least ES5
// answerPs.forEach(function (answerP) {
// Q(answerP).then(resolve, reject);
// });
// Use this in the meantime
for (var i = 0, len = answerPs.length; i < len; i++) {
Q(answerPs[i]).then(resolve, reject);
}
});
}
Promise.prototype.race = function () {
return this.then(Q.race);
};
/**
* Constructs a Promise with a promise descriptor object and optional fallback
* function. The descriptor contains methods like when(rejected), get(name),
* set(name, value), post(name, args), and delete(name), which all
* return either a value, a promise for a value, or a rejection. The fallback
* accepts the operation name, a resolver, and any further arguments that would
* have been forwarded to the appropriate method above had a method been
* provided with the proper name. The API makes no guarantees about the nature
* of the returned object, apart from that it is usable whereever promises are
* bought and sold.
*/
Q.makePromise = Promise;
function Promise(descriptor, fallback, inspect) {
if (fallback === void 0) {
fallback = function (op) {
return reject(new Error(
"Promise does not support operation: " + op
));
};
}
if (inspect === void 0) {
inspect = function () {
return {state: "unknown"};
};
}
var promise = object_create(Promise.prototype);
promise.promiseDispatch = function (resolve, op, args) {
var result;
try {
if (descriptor[op]) {
result = descriptor[op].apply(promise, args);
} else {
result = fallback.call(promise, op, args);
}
} catch (exception) {
result = reject(exception);
}
if (resolve) {
resolve(result);
}
};
promise.inspect = inspect;
// XXX deprecated `valueOf` and `exception` support
if (inspect) {
var inspected = inspect();
if (inspected.state === "rejected") {
promise.exception = inspected.reason;
}
promise.valueOf = function () {
var inspected = inspect();
if (inspected.state === "pending" ||
inspected.state === "rejected") {
return promise;
}
return inspected.value;
};
}
return promise;
}
Promise.prototype.toString = function () {
return "[object Promise]";
};
Promise.prototype.then = function (fulfilled, rejected, progressed) {
var self = this;
var deferred = defer();
var done = false; // ensure the untrusted promise makes at most a
// single call to one of the callbacks
function _fulfilled(value) {
try {
return typeof fulfilled === "function" ? fulfilled(value) : value;
} catch (exception) {
return reject(exception);
}
}
function _rejected(exception) {
if (typeof rejected === "function") {
makeStackTraceLong(exception, self);
try {
return rejected(exception);
} catch (newException) {
return reject(newException);
}
}
return reject(exception);
}
function _progressed(value) {
return typeof progressed === "function" ? progressed(value) : value;
}
Q.nextTick(function () {
self.promiseDispatch(function (value) {
if (done) {
return;
}
done = true;
deferred.resolve(_fulfilled(value));
}, "when", [function (exception) {
if (done) {
return;
}
done = true;
deferred.resolve(_rejected(exception));
}]);
});
// Progress propagator need to be attached in the current tick.
self.promiseDispatch(void 0, "when", [void 0, function (value) {
var newValue;
var threw = false;
try {
newValue = _progressed(value);
} catch (e) {
threw = true;
if (Q.onerror) {
Q.onerror(e);
} else {
throw e;
}
}
if (!threw) {
deferred.notify(newValue);
}
}]);
return deferred.promise;
};
Q.tap = function (promise, callback) {
return Q(promise).tap(callback);
};
/**
* Works almost like "finally", but not called for rejections.
* Original resolution value is passed through callback unaffected.
* Callback may return a promise that will be awaited for.
* @param {Function} callback
* @returns {Q.Promise}
* @example
* doSomething()
* .then(...)
* .tap(console.log)
* .then(...);
*/
Promise.prototype.tap = function (callback) {
callback = Q(callback);
return this.then(function (value) {
return callback.fcall(value).thenResolve(value);
});
};
/**
* Registers an observer on a promise.
*
* Guarantees:
*
* 1. that fulfilled and rejected will be called only once.
* 2. that either the fulfilled callback or the rejected callback will be
* called, but not both.
* 3. that fulfilled and rejected will not be called in this turn.
*
* @param value promise or immediate reference to observe
* @param fulfilled function to be called with the fulfilled value
* @param rejected function to be called with the rejection exception
* @param progressed function to be called on any progress notifications
* @return promise for the return value from the invoked callback
*/
Q.when = when;
function when(value, fulfilled, rejected, progressed) {
return Q(value).then(fulfilled, rejected, progressed);
}
Promise.prototype.thenResolve = function (value) {
return this.then(function () { return value; });
};
Q.thenResolve = function (promise, value) {
return Q(promise).thenResolve(value);
};
Promise.prototype.thenReject = function (reason) {
return this.then(function () { throw reason; });
};
Q.thenReject = function (promise, reason) {
return Q(promise).thenReject(reason);
};
/**
* If an object is not a promise, it is as "near" as possible.
* If a promise is rejected, it is as "near" as possible too.
* If it’s a fulfilled promise, the fulfillment value is nearer.
* If it’s a deferred promise and the deferred has been resolved, the
* resolution is "nearer".
* @param object
* @returns most resolved (nearest) form of the object
*/
// XXX should we re-do this?
Q.nearer = nearer;
function nearer(value) {
if (isPromise(value)) {
var inspected = value.inspect();
if (inspected.state === "fulfilled") {
return inspected.value;
}
}
return value;
}
/**
* @returns whether the given object is a promise.
* Otherwise it is a fulfilled value.
*/
Q.isPromise = isPromise;
function isPromise(object) {
return object instanceof Promise;
}
Q.isPromiseAlike = isPromiseAlike;
function isPromiseAlike(object) {
return isObject(object) && typeof object.then === "function";
}
/**
* @returns whether the given object is a pending promise, meaning not
* fulfilled or rejected.
*/
Q.isPending = isPending;
function isPending(object) {
return isPromise(object) && object.inspect().state === "pending";