1 files changed, 14 insertions, 0 deletions
diff --git a/testing/mochitest/tests/browser/browser_setup_runs_first.js b/testing/mochitest/tests/browser/browser_setup_runs_first.js
new file mode 100644
index 0000000000..6b9ce145da
--- /dev/null
+++ b/testing/mochitest/tests/browser/browser_setup_runs_first.js
@@ -0,0 +1,14 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+let someVar = 1;
+
+add_task(() => {
+  is(someVar, 2, "Should get updated by setup which runs first.");
+});
+
+add_setup(() => {
+  someVar = 2;
+});