diff -r 000000000000 -r 6474c204b198 browser/components/customizableui/test/browser_panel_toggle.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/customizableui/test/browser_panel_toggle.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,43 @@
+/* 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/. */
+
+"use strict";
+
+/**
+ * Test opening and closing the menu panel UI.
+ */
+
+// Show and hide the menu panel programmatically without an event (like UITour.jsm would)
+add_task(function() {
+  let shownPromise = promisePanelShown(window);
+  PanelUI.show();
+  yield shownPromise;
+
+  is(PanelUI.panel.getAttribute("panelopen"), "true", "Check that panel has panelopen attribute");
+  is(PanelUI.panel.state, "open", "Check that panel state is 'open'");
+
+  let hiddenPromise = promisePanelHidden(window);
+  PanelUI.hide();
+  yield hiddenPromise;
+
+  ok(!PanelUI.panel.hasAttribute("panelopen"), "Check that panel doesn't have the panelopen attribute");
+  is(PanelUI.panel.state, "closed", "Check that panel state is 'closed'");
+});
+
+// Toggle the menu panel open and closed
+add_task(function() {
+  let shownPromise = promisePanelShown(window);
+  PanelUI.toggle({type: "command"});
+  yield shownPromise;
+
+  is(PanelUI.panel.getAttribute("panelopen"), "true", "Check that panel has panelopen attribute");
+  is(PanelUI.panel.state, "open", "Check that panel state is 'open'");
+
+  let hiddenPromise = promisePanelHidden(window);
+  PanelUI.toggle({type: "command"});
+  yield hiddenPromise;
+
+  ok(!PanelUI.panel.hasAttribute("panelopen"), "Check that panel doesn't have the panelopen attribute");
+  is(PanelUI.panel.state, "closed", "Check that panel state is 'closed'");
+});