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// Copyright (C) 2020 Rick Waldron. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-performpromiserace
description: >
Promise.race does not prevent resolve from being called multiple times.
info: |
PerformPromiseRace
Repeat,
Let next be IteratorStep(iteratorRecord).
If next is an abrupt completion, set iteratorRecord.[[Done]] to true.
ReturnIfAbrupt(next).
If next is false, then
Set iteratorRecord.[[Done]] to true.
Return resultCapability.[[Promise]].
Let nextValue be IteratorValue(next).
If nextValue is an abrupt completion, set iteratorRecord.[[Done]] to true.
ReturnIfAbrupt(nextValue).
Let nextPromise be ? Call(promiseResolve, constructor, « nextValue »).
Perform ? Invoke(nextPromise, "then", « resultCapability.[[Resolve]], resultCapability.[[Reject]] »).
includes: [promiseHelper.js]
---*/
let callCount = 0;
let sequence = [];
function Constructor(executor) {
function resolve(value) {
callCount += 1;
sequence.push(value);
}
executor(resolve, Test262Error.thrower);
}
Constructor.resolve = function(v) {
return v;
};
let pResolve;
let a = {
then(resolver, rejector) {
pResolve = resolver;
}
};
assert.sameValue(callCount, 0, 'callCount before call to race()');
Promise.race.call(Constructor, [a]);
assert.sameValue(callCount, 0, 'callCount after call to race()');
pResolve(1);
pResolve(2);
pResolve(3);
assert.sameValue(callCount, 3, 'callCount after resolving a');
assert.sameValue(sequence.length, 3);
checkSequence(sequence);
reportCompare(0, 0);