es.promise.js 14 KB

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  1. 'use strict';
  2. var $ = require('../internals/export');
  3. var IS_PURE = require('../internals/is-pure');
  4. var global = require('../internals/global');
  5. var getBuiltIn = require('../internals/get-built-in');
  6. var call = require('../internals/function-call');
  7. var NativePromise = require('../internals/native-promise-constructor');
  8. var redefine = require('../internals/redefine');
  9. var redefineAll = require('../internals/redefine-all');
  10. var setPrototypeOf = require('../internals/object-set-prototype-of');
  11. var setToStringTag = require('../internals/set-to-string-tag');
  12. var setSpecies = require('../internals/set-species');
  13. var aCallable = require('../internals/a-callable');
  14. var isCallable = require('../internals/is-callable');
  15. var isObject = require('../internals/is-object');
  16. var anInstance = require('../internals/an-instance');
  17. var inspectSource = require('../internals/inspect-source');
  18. var iterate = require('../internals/iterate');
  19. var checkCorrectnessOfIteration = require('../internals/check-correctness-of-iteration');
  20. var speciesConstructor = require('../internals/species-constructor');
  21. var task = require('../internals/task').set;
  22. var microtask = require('../internals/microtask');
  23. var promiseResolve = require('../internals/promise-resolve');
  24. var hostReportErrors = require('../internals/host-report-errors');
  25. var newPromiseCapabilityModule = require('../internals/new-promise-capability');
  26. var perform = require('../internals/perform');
  27. var Queue = require('../internals/queue');
  28. var InternalStateModule = require('../internals/internal-state');
  29. var isForced = require('../internals/is-forced');
  30. var wellKnownSymbol = require('../internals/well-known-symbol');
  31. var IS_BROWSER = require('../internals/engine-is-browser');
  32. var IS_NODE = require('../internals/engine-is-node');
  33. var V8_VERSION = require('../internals/engine-v8-version');
  34. var SPECIES = wellKnownSymbol('species');
  35. var PROMISE = 'Promise';
  36. var getInternalState = InternalStateModule.getterFor(PROMISE);
  37. var setInternalState = InternalStateModule.set;
  38. var getInternalPromiseState = InternalStateModule.getterFor(PROMISE);
  39. var NativePromisePrototype = NativePromise && NativePromise.prototype;
  40. var PromiseConstructor = NativePromise;
  41. var PromisePrototype = NativePromisePrototype;
  42. var TypeError = global.TypeError;
  43. var document = global.document;
  44. var process = global.process;
  45. var newPromiseCapability = newPromiseCapabilityModule.f;
  46. var newGenericPromiseCapability = newPromiseCapability;
  47. var DISPATCH_EVENT = !!(document && document.createEvent && global.dispatchEvent);
  48. var NATIVE_REJECTION_EVENT = isCallable(global.PromiseRejectionEvent);
  49. var UNHANDLED_REJECTION = 'unhandledrejection';
  50. var REJECTION_HANDLED = 'rejectionhandled';
  51. var PENDING = 0;
  52. var FULFILLED = 1;
  53. var REJECTED = 2;
  54. var HANDLED = 1;
  55. var UNHANDLED = 2;
  56. var SUBCLASSING = false;
  57. var Internal, OwnPromiseCapability, PromiseWrapper, nativeThen;
  58. var FORCED = isForced(PROMISE, function () {
  59. var PROMISE_CONSTRUCTOR_SOURCE = inspectSource(PromiseConstructor);
  60. var GLOBAL_CORE_JS_PROMISE = PROMISE_CONSTRUCTOR_SOURCE !== String(PromiseConstructor);
  61. // V8 6.6 (Node 10 and Chrome 66) have a bug with resolving custom thenables
  62. // https://bugs.chromium.org/p/chromium/issues/detail?id=830565
  63. // We can't detect it synchronously, so just check versions
  64. if (!GLOBAL_CORE_JS_PROMISE && V8_VERSION === 66) return true;
  65. // We need Promise#finally in the pure version for preventing prototype pollution
  66. if (IS_PURE && !PromisePrototype['finally']) return true;
  67. // We can't use @@species feature detection in V8 since it causes
  68. // deoptimization and performance degradation
  69. // https://github.com/zloirock/core-js/issues/679
  70. if (V8_VERSION >= 51 && /native code/.test(PROMISE_CONSTRUCTOR_SOURCE)) return false;
  71. // Detect correctness of subclassing with @@species support
  72. var promise = new PromiseConstructor(function (resolve) { resolve(1); });
  73. var FakePromise = function (exec) {
  74. exec(function () { /* empty */ }, function () { /* empty */ });
  75. };
  76. var constructor = promise.constructor = {};
  77. constructor[SPECIES] = FakePromise;
  78. SUBCLASSING = promise.then(function () { /* empty */ }) instanceof FakePromise;
  79. if (!SUBCLASSING) return true;
  80. // Unhandled rejections tracking support, NodeJS Promise without it fails @@species test
  81. return !GLOBAL_CORE_JS_PROMISE && IS_BROWSER && !NATIVE_REJECTION_EVENT;
  82. });
  83. var INCORRECT_ITERATION = FORCED || !checkCorrectnessOfIteration(function (iterable) {
  84. PromiseConstructor.all(iterable)['catch'](function () { /* empty */ });
  85. });
  86. // helpers
  87. var isThenable = function (it) {
  88. var then;
  89. return isObject(it) && isCallable(then = it.then) ? then : false;
  90. };
  91. var callReaction = function (reaction, state) {
  92. var value = state.value;
  93. var ok = state.state == FULFILLED;
  94. var handler = ok ? reaction.ok : reaction.fail;
  95. var resolve = reaction.resolve;
  96. var reject = reaction.reject;
  97. var domain = reaction.domain;
  98. var result, then, exited;
  99. try {
  100. if (handler) {
  101. if (!ok) {
  102. if (state.rejection === UNHANDLED) onHandleUnhandled(state);
  103. state.rejection = HANDLED;
  104. }
  105. if (handler === true) result = value;
  106. else {
  107. if (domain) domain.enter();
  108. result = handler(value); // can throw
  109. if (domain) {
  110. domain.exit();
  111. exited = true;
  112. }
  113. }
  114. if (result === reaction.promise) {
  115. reject(TypeError('Promise-chain cycle'));
  116. } else if (then = isThenable(result)) {
  117. call(then, result, resolve, reject);
  118. } else resolve(result);
  119. } else reject(value);
  120. } catch (error) {
  121. if (domain && !exited) domain.exit();
  122. reject(error);
  123. }
  124. };
  125. var notify = function (state, isReject) {
  126. if (state.notified) return;
  127. state.notified = true;
  128. microtask(function () {
  129. var reactions = state.reactions;
  130. var reaction;
  131. while (reaction = reactions.get()) {
  132. callReaction(reaction, state);
  133. }
  134. state.notified = false;
  135. if (isReject && !state.rejection) onUnhandled(state);
  136. });
  137. };
  138. var dispatchEvent = function (name, promise, reason) {
  139. var event, handler;
  140. if (DISPATCH_EVENT) {
  141. event = document.createEvent('Event');
  142. event.promise = promise;
  143. event.reason = reason;
  144. event.initEvent(name, false, true);
  145. global.dispatchEvent(event);
  146. } else event = { promise: promise, reason: reason };
  147. if (!NATIVE_REJECTION_EVENT && (handler = global['on' + name])) handler(event);
  148. else if (name === UNHANDLED_REJECTION) hostReportErrors('Unhandled promise rejection', reason);
  149. };
  150. var onUnhandled = function (state) {
  151. call(task, global, function () {
  152. var promise = state.facade;
  153. var value = state.value;
  154. var IS_UNHANDLED = isUnhandled(state);
  155. var result;
  156. if (IS_UNHANDLED) {
  157. result = perform(function () {
  158. if (IS_NODE) {
  159. process.emit('unhandledRejection', value, promise);
  160. } else dispatchEvent(UNHANDLED_REJECTION, promise, value);
  161. });
  162. // Browsers should not trigger `rejectionHandled` event if it was handled here, NodeJS - should
  163. state.rejection = IS_NODE || isUnhandled(state) ? UNHANDLED : HANDLED;
  164. if (result.error) throw result.value;
  165. }
  166. });
  167. };
  168. var isUnhandled = function (state) {
  169. return state.rejection !== HANDLED && !state.parent;
  170. };
  171. var onHandleUnhandled = function (state) {
  172. call(task, global, function () {
  173. var promise = state.facade;
  174. if (IS_NODE) {
  175. process.emit('rejectionHandled', promise);
  176. } else dispatchEvent(REJECTION_HANDLED, promise, state.value);
  177. });
  178. };
  179. var bind = function (fn, state, unwrap) {
  180. return function (value) {
  181. fn(state, value, unwrap);
  182. };
  183. };
  184. var internalReject = function (state, value, unwrap) {
  185. if (state.done) return;
  186. state.done = true;
  187. if (unwrap) state = unwrap;
  188. state.value = value;
  189. state.state = REJECTED;
  190. notify(state, true);
  191. };
  192. var internalResolve = function (state, value, unwrap) {
  193. if (state.done) return;
  194. state.done = true;
  195. if (unwrap) state = unwrap;
  196. try {
  197. if (state.facade === value) throw TypeError("Promise can't be resolved itself");
  198. var then = isThenable(value);
  199. if (then) {
  200. microtask(function () {
  201. var wrapper = { done: false };
  202. try {
  203. call(then, value,
  204. bind(internalResolve, wrapper, state),
  205. bind(internalReject, wrapper, state)
  206. );
  207. } catch (error) {
  208. internalReject(wrapper, error, state);
  209. }
  210. });
  211. } else {
  212. state.value = value;
  213. state.state = FULFILLED;
  214. notify(state, false);
  215. }
  216. } catch (error) {
  217. internalReject({ done: false }, error, state);
  218. }
  219. };
  220. // constructor polyfill
  221. if (FORCED) {
  222. // 25.4.3.1 Promise(executor)
  223. PromiseConstructor = function Promise(executor) {
  224. anInstance(this, PromisePrototype);
  225. aCallable(executor);
  226. call(Internal, this);
  227. var state = getInternalState(this);
  228. try {
  229. executor(bind(internalResolve, state), bind(internalReject, state));
  230. } catch (error) {
  231. internalReject(state, error);
  232. }
  233. };
  234. PromisePrototype = PromiseConstructor.prototype;
  235. // eslint-disable-next-line no-unused-vars -- required for `.length`
  236. Internal = function Promise(executor) {
  237. setInternalState(this, {
  238. type: PROMISE,
  239. done: false,
  240. notified: false,
  241. parent: false,
  242. reactions: new Queue(),
  243. rejection: false,
  244. state: PENDING,
  245. value: undefined
  246. });
  247. };
  248. Internal.prototype = redefineAll(PromisePrototype, {
  249. // `Promise.prototype.then` method
  250. // https://tc39.es/ecma262/#sec-promise.prototype.then
  251. // eslint-disable-next-line unicorn/no-thenable -- safe
  252. then: function then(onFulfilled, onRejected) {
  253. var state = getInternalPromiseState(this);
  254. var reaction = newPromiseCapability(speciesConstructor(this, PromiseConstructor));
  255. state.parent = true;
  256. reaction.ok = isCallable(onFulfilled) ? onFulfilled : true;
  257. reaction.fail = isCallable(onRejected) && onRejected;
  258. reaction.domain = IS_NODE ? process.domain : undefined;
  259. if (state.state == PENDING) state.reactions.add(reaction);
  260. else microtask(function () {
  261. callReaction(reaction, state);
  262. });
  263. return reaction.promise;
  264. },
  265. // `Promise.prototype.catch` method
  266. // https://tc39.es/ecma262/#sec-promise.prototype.catch
  267. 'catch': function (onRejected) {
  268. return this.then(undefined, onRejected);
  269. }
  270. });
  271. OwnPromiseCapability = function () {
  272. var promise = new Internal();
  273. var state = getInternalState(promise);
  274. this.promise = promise;
  275. this.resolve = bind(internalResolve, state);
  276. this.reject = bind(internalReject, state);
  277. };
  278. newPromiseCapabilityModule.f = newPromiseCapability = function (C) {
  279. return C === PromiseConstructor || C === PromiseWrapper
  280. ? new OwnPromiseCapability(C)
  281. : newGenericPromiseCapability(C);
  282. };
  283. if (!IS_PURE && isCallable(NativePromise) && NativePromisePrototype !== Object.prototype) {
  284. nativeThen = NativePromisePrototype.then;
  285. if (!SUBCLASSING) {
  286. // make `Promise#then` return a polyfilled `Promise` for native promise-based APIs
  287. redefine(NativePromisePrototype, 'then', function then(onFulfilled, onRejected) {
  288. var that = this;
  289. return new PromiseConstructor(function (resolve, reject) {
  290. call(nativeThen, that, resolve, reject);
  291. }).then(onFulfilled, onRejected);
  292. // https://github.com/zloirock/core-js/issues/640
  293. }, { unsafe: true });
  294. // makes sure that native promise-based APIs `Promise#catch` properly works with patched `Promise#then`
  295. redefine(NativePromisePrototype, 'catch', PromisePrototype['catch'], { unsafe: true });
  296. }
  297. // make `.constructor === Promise` work for native promise-based APIs
  298. try {
  299. delete NativePromisePrototype.constructor;
  300. } catch (error) { /* empty */ }
  301. // make `instanceof Promise` work for native promise-based APIs
  302. if (setPrototypeOf) {
  303. setPrototypeOf(NativePromisePrototype, PromisePrototype);
  304. }
  305. }
  306. }
  307. $({ global: true, wrap: true, forced: FORCED }, {
  308. Promise: PromiseConstructor
  309. });
  310. setToStringTag(PromiseConstructor, PROMISE, false, true);
  311. setSpecies(PROMISE);
  312. PromiseWrapper = getBuiltIn(PROMISE);
  313. // statics
  314. $({ target: PROMISE, stat: true, forced: FORCED }, {
  315. // `Promise.reject` method
  316. // https://tc39.es/ecma262/#sec-promise.reject
  317. reject: function reject(r) {
  318. var capability = newPromiseCapability(this);
  319. call(capability.reject, undefined, r);
  320. return capability.promise;
  321. }
  322. });
  323. $({ target: PROMISE, stat: true, forced: IS_PURE || FORCED }, {
  324. // `Promise.resolve` method
  325. // https://tc39.es/ecma262/#sec-promise.resolve
  326. resolve: function resolve(x) {
  327. return promiseResolve(IS_PURE && this === PromiseWrapper ? PromiseConstructor : this, x);
  328. }
  329. });
  330. $({ target: PROMISE, stat: true, forced: INCORRECT_ITERATION }, {
  331. // `Promise.all` method
  332. // https://tc39.es/ecma262/#sec-promise.all
  333. all: function all(iterable) {
  334. var C = this;
  335. var capability = newPromiseCapability(C);
  336. var resolve = capability.resolve;
  337. var reject = capability.reject;
  338. var result = perform(function () {
  339. var $promiseResolve = aCallable(C.resolve);
  340. var values = [];
  341. var counter = 0;
  342. var remaining = 1;
  343. iterate(iterable, function (promise) {
  344. var index = counter++;
  345. var alreadyCalled = false;
  346. remaining++;
  347. call($promiseResolve, C, promise).then(function (value) {
  348. if (alreadyCalled) return;
  349. alreadyCalled = true;
  350. values[index] = value;
  351. --remaining || resolve(values);
  352. }, reject);
  353. });
  354. --remaining || resolve(values);
  355. });
  356. if (result.error) reject(result.value);
  357. return capability.promise;
  358. },
  359. // `Promise.race` method
  360. // https://tc39.es/ecma262/#sec-promise.race
  361. race: function race(iterable) {
  362. var C = this;
  363. var capability = newPromiseCapability(C);
  364. var reject = capability.reject;
  365. var result = perform(function () {
  366. var $promiseResolve = aCallable(C.resolve);
  367. iterate(iterable, function (promise) {
  368. call($promiseResolve, C, promise).then(capability.resolve, reject);
  369. });
  370. });
  371. if (result.error) reject(result.value);
  372. return capability.promise;
  373. }
  374. });