diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_3/Operators/11.13.1-002.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_3/Operators/11.13.1-002.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,24 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 312354;
+var summary = '11.13.1 Simple Assignment should return type of RHS';
+var actual = '';
+var expect = '';
+
+// XXX this test should really test each property of the native
+// objects, but I'm too lazy. Patches accepted.
+
+printBugNumber(BUGNUMBER);
+printStatus (summary);
+
+var re = /x/g;
+var y = re.lastIndex = "7";
+ 
+expect = "string";
+actual = typeof y;
+
+reportCompare(expect, actual, summary);