diff -r 000000000000 -r 6474c204b198 toolkit/modules/tests/xpcshell/test_timer.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/modules/tests/xpcshell/test_timer.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,30 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests exports from Timer.jsm
+
+let imported = {};
+Components.utils.import("resource://gre/modules/Timer.jsm", imported);
+
+function run_test(browser, tab, document) {
+  do_test_pending();
+
+  let timeout1 = imported.setTimeout(function() do_throw("Should not be called"), 100);
+  do_check_eq(typeof timeout1, "number", "setTimeout returns a number");
+  do_check_true(timeout1 > 0, "setTimeout returns a positive number");
+
+  let timeout2 = imported.setTimeout(function(param1, param2) {
+    do_check_true(true, "Should be called");
+    do_check_eq(param1, 5, "first parameter is correct");
+    do_check_eq(param2, "test", "second parameter is correct");
+    do_test_finished();
+  }, 100, 5, "test");
+
+  do_check_eq(typeof timeout2, "number", "setTimeout returns a number");
+  do_check_true(timeout2 > 0, "setTimeout returns a positive number");
+  do_check_neq(timeout1, timeout2, "Calling setTimeout again returns a different value");
+
+  imported.clearTimeout(timeout1);
+}