diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_3/extensions/regress-274152.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_3/extensions/regress-274152.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,48 @@
+/* -*- 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 = 274152;
+var summary = 'Do not ignore unicode format-control characters';
+var actual = '';
+var expect = '';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  expect = 'SyntaxError: illegal character';
+
+  var formatcontrolchars = ['\u200E',
+                            '\u0600', 
+                            '\u0601', 
+                            '\u0602', 
+                            '\u0603', 
+                            '\u06DD', 
+                            '\u070F'];
+
+  for (var i = 0; i < formatcontrolchars.length; i++)
+  {
+    try
+    {
+      eval("hi" + formatcontrolchars[i] + "there = 'howdie';");
+    }
+    catch(ex)
+    {
+      actual = ex + '';
+    }
+
+    reportCompare(expect, actual, summary + ': ' + i);
+  }
+
+  exitFunc ('test');
+}