| // 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.lastindexof |
| description: Returns -1 if length is 0 |
| info: | |
| 22.2.3.17 %TypedArray%.prototype.lastIndexOf ( searchElement [ , fromIndex ] ) |
| |
| %TypedArray%.prototype.lastIndexOf is a distinct function that implements the |
| same algorithm as Array.prototype.lastIndexOf as defined in 22.1.3.15 except |
| that the this object's [[ArrayLength]] internal slot is accessed in place of |
| performing a [[Get]] of "length". |
| |
| 22.1.3.15 Array.prototype.lastIndexOf ( searchElement [ , fromIndex ] ) |
| |
| ... |
| 2. Let len be ? ToLength(? Get(O, "length")). |
| 3. If len is 0, return -1. |
| ... |
| includes: [testBigIntTypedArray.js] |
| features: [BigInt, TypedArray] |
| ---*/ |
| |
| var fromIndex = { |
| valueOf: function() { |
| throw new Test262Error(); |
| } |
| }; |
| |
| testWithBigIntTypedArrayConstructors(function(TA) { |
| var sample = new TA(); |
| assert.sameValue(sample.lastIndexOf(0), -1, "returns -1"); |
| assert.sameValue( |
| sample.lastIndexOf(0n, fromIndex), -1, |
| "length is checked before ToInteger(fromIndex)" |
| ); |
| }); |