JSTests/test262/test/built-ins/Array/prototype/filter/15.4.4.20-9-b-12.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.filter
es5id: 15.4.4.20-9-b-12
description: >
    Array.prototype.filter - deleting own property with prototype
    property causes prototype index property to be visited on an
    Array-like object
---*/

        function callbackfn(val, idx, obj) {
            return true;
        }
        var obj = { 0: 0, 1: 111, 2: 2, length: 10 };

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

            Object.prototype[1] = 1;
            var newArr = Array.prototype.filter.call(obj, callbackfn);

assert.sameValue(newArr.length, 3, 'newArr.length');
assert.sameValue(newArr[1], 1, 'newArr[1]');