diff -r 000000000000 -r 6474c204b198 testing/xpcshell/example/unit/test_load.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/testing/xpcshell/example/unit/test_load.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,21 @@
+/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* 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 subscriptLoaded = false;
+
+function run_test() {
+  load("load_subscript.js");
+  do_check_true(subscriptLoaded);
+  subscriptLoaded = false;
+  try {
+    load("file_that_does_not_exist.js");
+    subscriptLoaded = true;
+  }
+  catch (ex) {
+    do_check_eq(ex.message.substring(0,16), "cannot open file");
+  }
+  do_check_false(subscriptLoaded, "load() should throw an error");
+}