diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/proxy/testDirectProxyPreventExtensions2.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/proxy/testDirectProxyPreventExtensions2.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,17 @@
+/*
+ * Call the trap with the handler as the this value and the target as the first
+ * argument.
+ */
+var target = {};
+var called = false;
+var handler = {
+    preventExtensions: function (target1) {
+        assertEq(this, handler);
+        assertEq(target1, target);
+        Object.preventExtensions(target1);
+        called = true;
+        return true;
+    }
+};
+Object.preventExtensions(new Proxy(target, handler));
+assertEq(called, true);