diff -r 000000000000 -r 6474c204b198 testing/xpcshell/example/unit/test_do_check_null.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/testing/xpcshell/example/unit/test_do_check_null.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,6 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function run_test() {
+  do_check_null(null);
+}