JSTests/ChakraCore/test/es5/valueof.js

//-------------------------------------------------------------------------------------------------------
// Copyright (C) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE.txt file in the project root for full license information.
//-------------------------------------------------------------------------------------------------------

 var x = {};

 WScript.Echo("x.valueOf()");
 try {
    x.valueOf();  //Fine - there's no way to inject null or undefined as the 'this' value
 }
 catch (e)
 {
    WScript.Echo(e);
 }

WScript.Echo("x.valueOf.call(undefined)");
 try {
    x.valueOf.call(undefined);  //SHOULD throw a TypeError in ES5/IE10
 }
 catch (e)
 {
    WScript.Echo(e);
 }

WScript.Echo("x.valueOf.call(null)");
 try {
    x.valueOf.call(null);  //SHOULD throw a TypeError in ES5/IE10
 }
 catch (e)
 {
    WScript.Echo(e);
 }

WScript.Echo("x.valueOf.call()");
 try {
    x.valueOf.call();  //SHOULD throw a TypeError in ES5/IE10
 }
 catch (e)
 {
    WScript.Echo(e);
 }

WScript.Echo("typeof x.valueOf.call(true)");
 WScript.Echo(typeof x.valueOf.call(true));  //SHOULD print 'object' in ES5/IE10

WScript.Echo("typeof x.valueOf.call(42)");
 WScript.Echo(typeof x.valueOf.call(42));  //SHOULD print 'object' in ES5/IE10

WScript.Echo("typeof x.valueOf.call('Hello')");
 WScript.Echo(typeof x.valueOf.call('Hello'));  //SHOULD print 'object' in ES5/IE10