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// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
(function(global, utils, extrasUtils) {
"use strict";
%CheckIsBootstrapping();
// -------------------------------------------------------------------
// Imports
var InternalArray = utils.InternalArray;
var promiseHandledBySymbol =
utils.ImportNow("promise_handled_by_symbol");
var promiseForwardingHandlerSymbol =
utils.ImportNow("promise_forwarding_handler_symbol");
var GlobalPromise = global.Promise;
// -------------------------------------------------------------------
// Core functionality.
function PromiseIdResolveHandler(x) { return x; }
function PromiseIdRejectHandler(r) { %_ReThrow(r); }
SET_PRIVATE(PromiseIdRejectHandler, promiseForwardingHandlerSymbol, true);
// -------------------------------------------------------------------
// Define exported functions.
// Combinators.
// ES#sec-promise.all
// Promise.all ( iterable )
function PromiseAll(iterable) {
if (!IS_RECEIVER(this)) {
throw %make_type_error(kCalledOnNonObject, "Promise.all");
}
// false debugEvent so that forwarding the rejection through all does not
// trigger redundant ExceptionEvents
var deferred = %new_promise_capability(this, false);
var resolutions = new InternalArray();
var count;
// For catch prediction, don't treat the .then calls as handling it;
// instead, recurse outwards.
var instrumenting = DEBUG_IS_ACTIVE;
if (instrumenting) {
SET_PRIVATE(deferred.reject, promiseForwardingHandlerSymbol, true);
}
function CreateResolveElementFunction(index, values, promiseCapability) {
var alreadyCalled = false;
return (x) => {
if (alreadyCalled === true) return;
alreadyCalled = true;
values[index] = x;
if (--count === 0) {
var valuesArray = [];
%MoveArrayContents(values, valuesArray);
%_Call(promiseCapability.resolve, UNDEFINED, valuesArray);
}
};
}
try {
var i = 0;
count = 1;
for (var value of iterable) {
var nextPromise = this.resolve(value);
++count;
var throwawayPromise = nextPromise.then(
CreateResolveElementFunction(i, resolutions, deferred),
deferred.reject);
// For catch prediction, mark that rejections here are semantically
// handled by the combined Promise.
if (instrumenting && %is_promise(throwawayPromise)) {
SET_PRIVATE(throwawayPromise, promiseHandledBySymbol, deferred.promise);
}
++i;
}
// 6.d
if (--count === 0) {
var valuesArray = [];
%MoveArrayContents(resolutions, valuesArray);
%_Call(deferred.resolve, UNDEFINED, valuesArray);
}
} catch (e) {
%_Call(deferred.reject, UNDEFINED, e);
}
return deferred.promise;
}
// ES#sec-promise.race
// Promise.race ( iterable )
function PromiseRace(iterable) {
if (!IS_RECEIVER(this)) {
throw %make_type_error(kCalledOnNonObject, PromiseRace);
}
// false debugEvent so that forwarding the rejection through race does not
// trigger redundant ExceptionEvents
var deferred = %new_promise_capability(this, false);
// For catch prediction, don't treat the .then calls as handling it;
// instead, recurse outwards.
var instrumenting = DEBUG_IS_ACTIVE;
if (instrumenting) {
SET_PRIVATE(deferred.reject, promiseForwardingHandlerSymbol, true);
}
try {
for (var value of iterable) {
var throwawayPromise = this.resolve(value).then(deferred.resolve,
deferred.reject);
// For catch prediction, mark that rejections here are semantically
// handled by the combined Promise.
if (instrumenting && %is_promise(throwawayPromise)) {
SET_PRIVATE(throwawayPromise, promiseHandledBySymbol, deferred.promise);
}
}
} catch (e) {
%_Call(deferred.reject, UNDEFINED, e);
}
return deferred.promise;
}
// -------------------------------------------------------------------
// Install exported functions.
utils.InstallFunctions(GlobalPromise, DONT_ENUM, [
"all", PromiseAll,
"race", PromiseRace,
]);
%InstallToContext([
"promise_id_resolve_handler", PromiseIdResolveHandler,
"promise_id_reject_handler", PromiseIdRejectHandler
]);
})
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