diff -r 000000000000 -r 6474c204b198 intl/uconv/tests/unit/test_bug522931.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/intl/uconv/tests/unit/test_bug522931.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,6 @@
+// crash test with invaild parameter (bug 522931)
+function run_test()
+{
+  var textToSubURI = Components.classes["@mozilla.org/intl/texttosuburi;1"].getService(Components.interfaces.nsITextToSubURI);
+  do_check_eq(textToSubURI.UnEscapeAndConvert("UTF-8", null), "");
+}