test262/test/built-ins/Promise/race/invoke-then.js

56 lines
1.5 KiB
JavaScript

// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
description: >
Invocation of the instance's `then` method
es6id: 25.4.4.3
info: >
11. Let result be PerformPromiseRace(iteratorRecord, C, promiseCapability).
[...]
25.4.4.3.1 Runtime Semantics: PerformPromiseRace
1. Repeat
[...]
j. Let result be Invoke(nextPromise, "then",
«promiseCapability.[[Resolve]], promiseCapability.[[Reject]]»).
k. ReturnIfAbrupt(result).
---*/
var p1 = new Promise(function() {});
var p2 = new Promise(function() {});
var p3 = new Promise(function() {});
var callCount = 0;
var currentThis = p1;
var nextThis = p2;
var afterNextThis = p3;
p1.then = p2.then = p3.then = function(a, b) {
assert.sameValue(typeof a, 'function', 'type of first argument');
assert.sameValue(
a.length,
1,
'ES6 25.4.1.3.2: The length property of a promise resolve function is 1.'
);
assert.sameValue(typeof b, 'function', 'type of second argument');
assert.sameValue(
b.length,
1,
'ES6 25.4.1.3.1: The length property of a promise reject function is 1.'
);
assert.sameValue(arguments.length, 2, '`then` invoked with two arguments');
assert.sameValue(this, currentThis, '`this` value');
currentThis = nextThis;
nextThis = afterNextThis;
afterNextThis = null;
callCount += 1;
};
Promise.race([p1, p2, p3]);
assert.sameValue(callCount, 3, '`then` invoked once for every iterated value');