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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-%typedarray%.prototype.copywithin
description: >
Copy values with non-negative target, start and end positions.
info: |
22.2.3.5 %TypedArray%.prototype.copyWithin (target, start [ , end ] )
%TypedArray%.prototype.copyWithin is a distinct function that implements the
same algorithm as Array.prototype.copyWithin as defined in 22.1.3.3 except
that the this object's [[ArrayLength]] internal slot is accessed in place of
performing a [[Get]] of "length" and the actual copying of values in step 12
must be performed in a manner that preserves the bit-level encoding of the
source data.
...
includes: [compareArray.js, testTypedArray.js]
features: [TypedArray]
---*/
testWithTypedArrayConstructors(function(TA) {
assert(
compareArray(
new TA([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(
new TA([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(
new TA([0, 1, 2, 3]).copyWithin(0, 1, 2),
[1, 1, 2, 3]
),
'[0, 1, 2, 3].copyWithin(0, 1, 2) -> [1, 1, 2, 3]'
);
/*
* 10. If from<to and to<from+count, then
* 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(
new TA([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(
new TA([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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