invoke-then.js - mozsearch

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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: >

  Invocation of the instance's `then` method

esid: sec-promise.allsettled

info: |

  6. Let result be PerformPromiseAllSettled(iteratorRecord, C, promiseCapability).

  7. If result is an abrupt completion, then

    a. If iteratorRecord.[[Done]] is false, set result to IteratorClose(iteratorRecord, result).

    b. IfAbruptRejectPromise(result, promiseCapability).

  Runtime Semantics: PerformPromiseAllSettled

  z. Perform ? Invoke(nextPromise, "then", « resolveElement, rejectElement »).

features: [Promise.allSettled]

---*/

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,

    'The length property of a promise resolve function is 1.'

);

  assert.sameValue(typeof b, 'function', 'type of second argument');

  assert.sameValue(

    b.length,

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.allSettled([p1, p2, p3]);

assert.sameValue(callCount, 3, '`then` invoked once for every iterated value');

reportCompare(0, 0);