diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_3/extensions/regress-430740.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_3/extensions/regress-430740.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,39 @@
+/* -*- 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 = 430740;
+var summary = 'Do not strip format-control characters from string literals';
+var actual = '';
+var expect = '';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  function doevil() {
+    print('evildone');
+    return 'evildone';
+  }
+
+  expect = 'a%E2%80%8D,+doevil()%5D)//';
+  actual += eval("(['a\\\u200d', '+doevil()])//'])");
+  actual = encodeURI(actual);
+  reportCompare(expect, actual, summary);
+
+  expect = 'a%EF%BF%BE,+doevil()%5D)//';
+  actual = eval("(['a\\\ufffe', '+doevil()])//'])"); 
+  actual = encodeURI(actual);
+  reportCompare(expect, actual, summary);
+
+  exitFunc ('test');
+}