| // 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: > |
| Set values with negative start argument. |
| 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. |
| |
| ... |
| |
| 22.1.3.3 Array.prototype.copyWithin (target, start [ , end ] ) |
| |
| ... |
| 6. If relativeStart < 0, let from be max((len + relativeStart), 0); else let |
| from be min(relativeStart, len). |
| ... |
| includes: [compareArray.js, testTypedArray.js] |
| features: [TypedArray] |
| ---*/ |
| |
| testWithTypedArrayConstructors(function(TA) { |
| assert( |
| compareArray( |
| new TA([0, 1, 2, 3]).copyWithin(0, -1), |
| [3, 1, 2, 3] |
| ), |
| '[0, 1, 2, 3].copyWithin(0, -1) -> [3, 1, 2, 3]' |
| ); |
| |
| assert( |
| compareArray( |
| new TA([0, 1, 2, 3, 4]).copyWithin(2, -2), |
| [0, 1, 3, 4, 4] |
| ), |
| '[0, 1, 2, 3, 4].copyWithin(2, -2) -> [0, 1, 3, 4, 4]' |
| ); |
| |
| assert( |
| compareArray( |
| new TA([0, 1, 2, 3, 4]).copyWithin(1, -2), |
| [0, 3, 4, 3, 4] |
| ), |
| '[0, 1, 2, 3, 4].copyWithin(1, -2) -> [0, 3, 4, 3, 4]' |
| ); |
| |
| assert( |
| compareArray( |
| new TA([0, 1, 2, 3]).copyWithin(-1, -2), |
| [0, 1, 2, 2] |
| ), |
| '[0, 1, 2, 3].copyWithin(-1, -2) -> [ 0, 1, 2, 2 ]' |
| ); |
| |
| assert( |
| compareArray( |
| new TA([0, 1, 2, 3, 4]).copyWithin(-2, -3), |
| [0, 1, 2, 2, 3] |
| ), |
| '[0, 1, 2, 3, 4].copyWithin(-2, -3) -> [0, 1, 2, 2, 3]' |
| ); |
| |
| assert( |
| compareArray( |
| new TA([0, 1, 2, 3, 4]).copyWithin(-5, -2), |
| [3, 4, 2, 3, 4] |
| ), |
| '[0, 1, 2, 3, 4].copyWithin(-5, -2) -> [3, 4, 2, 3, 4]' |
| ); |
| }); |