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// Copyright (C) 2021 Microsoft. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.prototype.findlast
description: >
Return undefined if predicate always returns a boolean false value.
info: |
Array.prototype.findLast ( predicate[ , thisArg ] )
...
5. Repeat, while k ≥ 0,
...
c. Let testResult be ! ToBoolean(? Call(predicate, thisArg, « kValue, 𝔽(k), O »)).
...
6. Return undefined.
features: [Symbol, array-find-from-last]
---*/
var arr = ['Shoes', 'Car', 'Bike'];
var called = 0;
var result = arr.findLast(function() {
called++;
return false;
});
assert.sameValue(called, 3, 'predicate was called three times');
assert.sameValue(result, undefined);
result = arr.findLast(function() {
return '';
});
assert.sameValue(result, undefined, 'coerced string');
result = arr.findLast(function() {
return undefined;
});
assert.sameValue(result, undefined, 'coerced undefined');
result = arr.findLast(function() {
return null;
});
assert.sameValue(result, undefined, 'coerced null');
result = arr.findLast(function() {
return 0;
});
assert.sameValue(result, undefined, 'coerced 0');
result = arr.findLast(function() {
return NaN;
});
assert.sameValue(result, undefined, 'coerced NaN');
reportCompare(0, 0);
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