Add Array#copyWithin test

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Alexey Shvayka 2020-02-23 22:49:41 +02:00 committed by Rick Waldron
parent 2724ddc618
commit 5885db1361

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@ -0,0 +1,43 @@
// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.prototype.copywithin
description: >
Elements are copied and deleted in an array-like object
whose "length" property is near the integer limit.
info: |
Array.prototype.copyWithin ( target, start [ , end ] )
1. Let O be ? ToObject(this value).
2. Let len be ? LengthOfArrayLike(O).
[...]
9. Let count be min(final - from, len - to).
[...]
12. Repeat, while count > 0
[...]
d. If fromPresent is true, then
i. Let fromVal be ? Get(O, fromKey).
ii. Perform ? Set(O, toKey, fromVal, true).
e. Else,
i. Assert: fromPresent is false.
ii. Perform ? DeletePropertyOrThrow(O, toKey).
[...]
---*/
var startIndex = Number.MAX_SAFE_INTEGER - 3;
var arrayLike = {
0: 0,
1: 1,
2: 2,
length: Number.MAX_SAFE_INTEGER,
};
arrayLike[startIndex] = -3;
arrayLike[startIndex + 2] = -1;
Array.prototype.copyWithin.call(arrayLike, 0, startIndex, startIndex + 3);
assert.sameValue(arrayLike[0], -3);
assert.sameValue(1 in arrayLike, false);
assert.sameValue(arrayLike[2], -1);