JSTests/test262/test/built-ins/Array/prototype/indexOf/15.4.4.14-2-3.js

// 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.indexof
es5id: 15.4.4.14-2-3
description: >
    Array.prototype.indexOf - 'length' is own data property that
    overrides an inherited data property on an Array-like object
---*/

        var proto = { length: 0 };

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

        var child = new Con();
        child.length = 2;
        child[1] = true;

assert.sameValue(Array.prototype.indexOf.call(child, true), 1, 'Array.prototype.indexOf.call(child, true)');