test262/test/built-ins/Object/defineProperty/15.2.3.6-4-405.js

// Copyright (c) 2012 Ecma International.  All rights reserved.
// Ecma International makes this code available under the terms and conditions set
// forth on http://hg.ecmascript.org/tests/test262/raw-file/tip/LICENSE (the
// "Use Terms").   Any redistribution of this code must retain the above
// copyright and this notice and otherwise comply with the Use Terms.

/*---
es5id: 15.2.3.6-4-405
description: >
    ES5 Attributes - Failed to add a property to an object when the
    object's object has a property with same name and [[Writable]]
    attribute is set to false (Number instance)
includes: [propertyHelper.js]
---*/

        try {
            Object.defineProperty(Number.prototype, "prop", {
                value: 1001,
                writable: false,
                enumerable: false,
                configurable: true
            });
            var numObj = new Number();
            numObj.prop = 1002;

            return !numObj.hasOwnProperty("prop") && numObj.prop === 1001;
        } finally {
            delete Number.prototype.prop;
        }
    }