test/built-ins/Array/prototype/lastIndexOf/15.4.4.15-2-5.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: 15.4.4.15-2-5
description: >
    Array.prototype.lastIndexOf - 'length' is own data property that
    overrides an inherited accessor property on an Array-like object
---*/

        var proto = {};
        Object.defineProperty(proto, "length", {
            get: function () {
                return 0;
            },
            configurable: true
        });

        var Con = function () {};
        Con.prototype = proto;

        var child = new Con();

        Object.defineProperty(child, "length", {
            value: 2,
            configurable: true
        });
        child[1] = null;

assert.sameValue(Array.prototype.lastIndexOf.call(child, null), 1, 'Array.prototype.lastIndexOf.call(child, null)');