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// Copyright (C) 2019 Leo Balter. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
description: >
Gets constructor's `resolve` method once from zero to many invocations.
esid: sec-promise.race
info: |
Runtime Semantics: PerformPromiseRace
1. Let promiseResolve be ? Get(constructor, `"resolve"`).
1. If IsCallable(promiseResolve) is false, throw a TypeError exception.
...
1. Repeat,
...
1. Let nextPromise be ? Call(promiseResolve, constructor, « nextValue »).
---*/
var p1 = Promise.resolve(1);
var p2 = Promise.resolve(1);
var p3 = Promise.reject(1);
var p4 = Promise.resolve(1);
var resolve = Promise.resolve;
var getCount = 0;
var callCount = 0;
Object.defineProperty(Promise, 'resolve', {
configurable: true,
get() {
getCount += 1;
return function() {
callCount += 1;
return resolve.apply(Promise, arguments);
};
}
});
Promise.race([p1, p2, p3, p4]);
assert.sameValue(
getCount, 1, 'Got `resolve` only once for each iterated value'
);
assert.sameValue(
callCount, 4, '`resolve` invoked once for each iterated value'
);
reportCompare(0, 0);
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