diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/proxy/testDirectProxyKeys9.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/proxy/testDirectProxyKeys9.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,26 @@
+// Return the names returned by the trap
+var names = Object.keys(new Proxy(Object.create(Object.create(null, {
+    a: {
+        enumerable: true,
+        configurable: true
+    },
+    b: {
+        enumerable: false,
+        configurable: true
+    }
+}), {
+    c: {
+        enumerable: true,
+        configurable: true
+    },
+    d: {
+        enumerable: false,
+        configurable: true
+    }
+}), {
+    keys: function (target) {
+        return [ 'e' ];
+    }
+}));
+assertEq(names.length, 1);
+assertEq(names[0], 'e');