diff -r 000000000000 -r 6474c204b198 addon-sdk/source/test/test-addon-window.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/addon-sdk/source/test/test-addon-window.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,22 @@
+/* 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';
+
+let { Loader } = require('sdk/test/loader');
+
+exports.testReady = function(assert, done) {
+  let loader = Loader(module);
+  let { ready, window } = loader.require('sdk/addon/window');
+  let windowIsReady = false;
+
+  ready.then(function() {
+    assert.equal(windowIsReady, false, 'ready promise was resolved only once');
+    windowIsReady = true;
+
+    loader.unload();
+    done();
+  }).then(null, assert.fail);
+}
+
+require('sdk/test').run(exports);