diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_7/geniter/iterator-toString.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_7/geniter/iterator-toString.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,43 @@
+/* -*- 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     = "(none)";
+var summary = "gen.toString() omitting 'yield' from value";
+var actual, expect;
+
+printBugNumber(BUGNUMBER);
+printStatus(summary);
+
+/**************
+ * BEGIN TEST *
+ **************/
+
+var failed = false;
+
+function gen()
+{
+  yield 17;
+}
+
+try
+{
+  var str = gen.toString();
+  var index = str.search(/yield/);
+
+  if (index < 0)
+    throw "yield not found in str: " + str;
+}
+catch (e)
+{
+  failed = e;
+}
+
+
+
+expect = false;
+actual = failed;
+
+reportCompare(expect, actual, summary);