<!DOCTYPE HTML> <html> <!-- https://bugzilla.mozilla.org/show_bug.cgi?id=693615 --> <head> <title>Test for Bug 693615</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=693615">Mozilla Bug 693615</a> <p id="display"></p> <div id="content" style="display: none"> </div> <pre id="test"> <script type="application/javascript"> /** Test for Bug 693615 **/ /* The following code tests if calling the DOM method Node::lookupNamespaceURI directly (with quickstubs) and through XPCOM leads to the same result. */ var content = document.getElementById("content"); // called directly (quickstubs) var defaultNS = content.lookupNamespaceURI(null); is(defaultNS, null, "direct access working"); // called via XPCOM // deleting the method from the prototype forces the engine to go through XPCOM var proto = Object.getPrototypeOf(content); delete(proto.lookupNamespaceURI); var wrapperNS = content.lookupNamespaceURI(null); is(wrapperNS, null, "access through XPCOM working"); </script> </pre> </body> </html>