diff -r 000000000000 -r 6474c204b198 testing/mochitest/tests/browser/browser_head.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/testing/mochitest/tests/browser/browser_head.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,12 @@
+let testVar;
+
+registerCleanupFunction(function() {
+  ok(true, "I'm a cleanup function in test file");
+  is(this.testVar, "I'm a var in test file", "Test cleanup function scope is correct");
+});
+
+function test() {
+  is(headVar, "I'm a var in head file", "Head variables are set");
+  ok(headMethod(), "Head methods are imported");
+  testVar = "I'm a var in test file";
+}