js/src/tests/test262/built-ins/Array/prototype/lastIndexOf/length-zero-returns-minus-one.js


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// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.prototype.lastindexof
description: >
  Returns -1 if length is 0.
info: |
  Array.prototype.lastIndexOf ( searchElement [ , fromIndex ] )

  1. Let O be ? ToObject(this value).
  2. Let len be ? LengthOfArrayLike(O).
  3. If len is 0, return -1.
---*/

var fromIndex = {
  valueOf: function() {
    throw new Test262Error("Length should be checked before ToInteger(fromIndex).");
  },
};

assert.sameValue([].lastIndexOf(1), -1);
assert.sameValue([].lastIndexOf(2, fromIndex), -1);

reportCompare(0, 0);