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// Copyright (C) 2020 Rick Waldron. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-%typedarray%.prototype.at
description: >
Returns the item value at the specified index, holes are filled in sparse arrays.
info: |
%TypedArray%.prototype.at( index )
Let O be the this value.
Perform ? ValidateTypedArray(O).
Let len be O.[[ArrayLength]].
Let relativeIndex be ? ToInteger(index).
If relativeIndex ≥ 0, then
Let k be relativeIndex.
Else,
Let k be len + relativeIndex.
If k < 0 or k ≥ len, then return undefined.
Return ? Get(O, ! ToString(k)).
includes: [testTypedArray.js]
features: [TypedArray, TypedArray.prototype.at]
---*/
assert.sameValue(
typeof TypedArray.prototype.at,
'function',
'The value of `typeof TypedArray.prototype.at` is "function"'
);
testWithTypedArrayConstructors(TA => {
let a = new TA([0, 1, , 3, 4, , 6]);
let filler = 0;
if (TA.name.startsWith('Float')) {
filler = NaN;
}
assert.sameValue(a.at(0), 0, 'a.at(0) must return 0');
assert.sameValue(a.at(1), 1, 'a.at(1) must return 1');
assert.sameValue(a.at(2), filler, 'a.at(2) must return the value of filler');
assert.sameValue(a.at(3), 3, 'a.at(3) must return 3');
assert.sameValue(a.at(4), 4, 'a.at(4) must return 4');
assert.sameValue(a.at(5), filler, 'a.at(5) must return the value of filler');
assert.sameValue(a.at(6), 6, 'a.at(6) must return 6');
assert.sameValue(a.at(-0), 0, 'a.at(-0) must return 0');
assert.sameValue(a.at(-1), 6, 'a.at(-1) must return 6');
assert.sameValue(a.at(-2), filler, 'a.at(-2) must return the value of filler');
assert.sameValue(a.at(-3), 4, 'a.at(-3) must return 4');
assert.sameValue(a.at(-4), 3, 'a.at(-4) must return 3');
assert.sameValue(a.at(-5), filler, 'a.at(-5) must return the value of filler');
assert.sameValue(a.at(-6), 1, 'a.at(-6) must return 1');
});
reportCompare(0, 0);
|