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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.findlastindex
description: >
Return index if predicate return a boolean true value.
info: |
Array.prototype.findLastIndex ( predicate[ , thisArg ] )
...
5. Repeat, while k ≥ 0,
...
c. Let testResult be ! ToBoolean(? Call(predicate, thisArg, « kValue, 𝔽(k), O »)).
d. If testResult is true, return 𝔽(k).
...
features: [Symbol, array-find-from-last]
---*/
var arr = ['Shoes', 'Car', 'Bike'];
var called = 0;
var result = arr.findLastIndex(function() {
called++;
return true;
});
assert.sameValue(result, 2);
assert.sameValue(called, 1, 'predicate was called once');
called = 0;
result = arr.findLastIndex(function(val) {
called++;
return val === 'Shoes';
});
assert.sameValue(called, 3, 'predicate was called three times');
assert.sameValue(result, 0);
result = arr.findLastIndex(function() {
return 'string';
});
assert.sameValue(result, 2, 'coerced string');
result = arr.findLastIndex(function() {
return {};
});
assert.sameValue(result, 2, 'coerced object');
result = arr.findLastIndex(function() {
return Symbol('');
});
assert.sameValue(result, 2, 'coerced Symbol');
result = arr.findLastIndex(function() {
return 1;
});
assert.sameValue(result, 2, 'coerced number');
result = arr.findLastIndex(function() {
return -1;
});
assert.sameValue(result, 2, 'coerced negative number');
reportCompare(0, 0);
|