diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_5/LexicalConventions/regress-177314.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_5/LexicalConventions/regress-177314.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,76 @@
+/* -*- 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/. */
+
+/*
+ *
+ * Date:    30 Oct 2002
+ * SUMMARY: '\400' should lex as a 2-digit octal escape + '0'
+ * See http://bugzilla.mozilla.org/show_bug.cgi?id=177314
+ *
+ * Bug was that Rhino interpreted '\400' as a 3-digit octal escape. As such
+ * it is invalid, since octal escapes may only run from '\0' to '\377'. But
+ * the lexer should interpret this as '\40' + '0' instead, and throw no error.
+ *
+ */
+//-----------------------------------------------------------------------------
+var UBound = 0;
+var BUGNUMBER = 177314;
+var summary = "'\\" + "400' should lex as a 2-digit octal escape + '0'";
+var status = '';
+var statusitems = [];
+var actual = '';
+var actualvalues = [];
+var expect= '';
+var expectedvalues = [];
+
+
+// the last valid octal escape is '\377', which should equal hex escape '\xFF'
+status = inSection(1);
+actual = '\377';
+expect = '\xFF';
+addThis();
+
+// now exercise the lexer by going one higher in the last digit
+status = inSection(2);
+actual = '\378';
+expect = '\37' + '8';
+addThis();
+
+// trickier: 400 is a valid octal number, but '\400' isn't a valid octal escape
+status = inSection(3);
+actual = '\400';
+expect = '\40' + '0';
+addThis();
+
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+
+
+function addThis()
+{
+  statusitems[UBound] = status;
+  actualvalues[UBound] = actual;
+  expectedvalues[UBound] = expect;
+  UBound++;
+}
+
+
+function test()
+{
+  enterFunc('test');
+  printBugNumber(BUGNUMBER);
+  printStatus(summary);
+
+  for (var i=0; i<UBound; i++)
+  {
+    reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);
+  }
+
+  exitFunc ('test');
+}