<!DOCTYPE HTML> <html> <!-- https://bugzilla.mozilla.org/show_bug.cgi?id=793969 --> <head> <meta charset="utf-8"> <title>Test for Bug 793969</title> <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script> <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/> </head> <body> <a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=793969">Mozilla Bug 793969</a> <p id="display"></p> <div id="content" style="display: none"> </div> <pre id="test"> <script type="application/javascript"> /** Test for Bug 793969 **/ function checkThrows(f, desc, skipMessageCheck) { try { f(); ok(false, "Should have thrown for " + desc); } catch (e) { ok(true, "threw correctly"); if (!skipMessageCheck) ok(/denied/.exec(e) || /can't redefine non-configurable property/.exec(e), "Correctly threw a security exception: " + e); } } // NB: These sets will be no-ops (throw in strict mode) because setting an inherited readonly value prop has those semantics. checkThrows(function() { "use strict"; location.valueOf = 'hah'; }, 'Shadow with string', /* skipMessageCheck = */ true); checkThrows(function() { "use strict"; location.valueOf = function() { return {a: 'hah'};} }, 'Shadow with function', /* skipMessageCheck = */ true); checkThrows(function() { Object.defineProperty(location, 'valueOf', { value: function() { return 'hah'; } }); }, 'defineProperty with value'); checkThrows(function() { delete location.valueOf; Object.defineProperty(location, 'valueOf', { value: function() { return 'hah'; } }); }, 'delete + defineProperty with value'); checkThrows(function() { Object.defineProperty(location, 'valueOf', { get: function() { return 'hah'; } }); }, 'defineProperty with getter'); checkThrows(function() { delete location.valueOf; Object.defineProperty(location, 'valueOf', { get: function() { return 'hah'; } }); }, 'delete + defineProperty with getter'); Object.prototype.valueOf = function() { return 'hah'; }; is(({}).valueOf(), 'hah', "Shadowing on Object.prototype works for vanilla objects"); is(location.valueOf(), location, "Shadowing on Object.prototype and Location.prototype doesn't for location objects"); location[Symbol.toPrimitive] = function() { return 'hah'; } is(location + "", location.toString(), "Should't be able to shadow with toPrimitive"); </script> </pre> </body> </html>