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// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.prototype.copywithin
es6id: 22.1.3.3
description: >
Copy values with non-negative target, start and end positions.
info: |
22.1.3.3 Array.prototype.copyWithin (target, start [ , end ] )
...
7. If relativeTarget < 0, let to be max((len + relativeTarget),0); else let to
be min(relativeTarget, len).
...
10. If relativeStart < 0, let from be max((len + relativeStart),0); else let
from be min(relativeStart, len).
11. If end is undefined, let relativeEnd be len; else let relativeEnd be
ToInteger(end).
...
14. Let count be min(final-from, len-to).
15. If from<to and to<from+count
a. Let direction be -1.
b. Let from be from + count -1.
c. Let to be to + count -1.
16. Else,
a. Let direction = 1.
17. Repeat, while count > 0
...
a. If fromPresent is true, then
i. Let fromVal be Get(O, fromKey).
...
iii. Let setStatus be Set(O, toKey, fromVal, true).
...
includes: [compareArray.js]
---*/
assert(
compareArray(
[0, 1, 2, 3].copyWithin(0, 0, 0), [0, 1, 2, 3]
),
'[0, 1, 2, 3].copyWithin(0, 0, 0) -> [0, 1, 2, 3]'
);
assert(
compareArray(
[0, 1, 2, 3].copyWithin(0, 0, 2), [0, 1, 2, 3]
),
'[0, 1, 2, 3].copyWithin(0, 0, 2) -> [0, 1, 2, 3]'
);
assert(
compareArray(
[0, 1, 2, 3].copyWithin(0, 1, 2), [1, 1, 2, 3]
),
'[0, 1, 2, 3].copyWithin(0, 1, 2) -> [1, 1, 2, 3]'
);
/*
* 15. If from<to and to<from+count
* a. Let direction be -1.
* b. Let from be from + count -1.
* c. Let to be to + count -1.
*
* 0 < 1, 1 < 0 + 2
* direction = -1
* from = 0 + 2 - 1
* to = 1 + 2 - 1
*/
assert(
compareArray(
[0, 1, 2, 3].copyWithin(1, 0, 2), [0, 0, 1, 3]
),
'[0, 1, 2, 3].copyWithin(1, 0, 2) -> [0, 0, 1, 3]'
);
assert(
compareArray(
[0, 1, 2, 3, 4, 5].copyWithin(1, 3, 5), [0, 3, 4, 3, 4, 5]
),
'[0, 1, 2, 3, 4, 5].copyWithin(1, 3, 5) -> [0, 3, 4, 3, 4, 5]'
);
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