js/src/tests/test262/built-ins/Iterator/prototype/find/this-plain-iterator.js


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33

// |reftest| shell-option(--enable-iterator-helpers) skip-if(!this.hasOwnProperty('Iterator')||!xulRuntime.shell) -- iterator-helpers is not enabled unconditionally, requires shell-options
// Copyright (C) 2023 Michael Ficarra. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-iteratorprototype.find
description: >
  Iterator.prototype.find supports a this value that does not inherit from Iterator.prototype but implements the iterator protocol
info: |
  %Iterator.prototype%.find ( predicate )

features: [iterator-helpers]
flags: []
---*/
let iter = {
  get next() {
    let count = 3;
    return function () {
      --count;
      return count >= 0 ? { done: false, value: count } : { done: true, value: undefined };
    };
  },
};

let predicateCalls = 0;
let result = Iterator.prototype.find.call(iter, function (v) {
  ++predicateCalls;
  return v === 0;
});

assert.sameValue(result, 0);
assert.sameValue(predicateCalls, 3);

reportCompare(0, 0);