test/built-ins/Array/prototype/lastIndexOf/15.4.4.15-8-a-12.js


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// Copyright (c) 2012 Ecma International.  All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
esid: sec-array.prototype.lastindexof
es5id: 15.4.4.15-8-a-12
description: >
    Array.prototype.lastIndexOf - deleting own property causes index
    property not to be visited on an Array
---*/

        var arr = [1, 2, 3, 4];

        Object.defineProperty(arr, "1", {
            get: function () {
                return "6.99";
            },
            configurable: true
        });

        Object.defineProperty(arr, "3", {
            get: function () {
                delete arr[1];
                return 0;
            },
            configurable: true
        });

assert.sameValue(arr.lastIndexOf("6.99"), -1, 'arr.lastIndexOf("6.99")');