1 files changed, 78 insertions, 0 deletions
diff --git a/browser/base/content/test/notificationbox/browser_notification_stacking.js b/browser/base/content/test/notificationbox/browser_notification_stacking.js
new file mode 100644
index 0000000000..bd8817ea4b
--- /dev/null
+++ b/browser/base/content/test/notificationbox/browser_notification_stacking.js
@@ -0,0 +1,78 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+async function addNotification(box, label, value, priorityName) {
+  let added = BrowserTestUtils.waitForNotificationInNotificationBox(box, value);
+  let priority = gNotificationBox[`PRIORITY_${priorityName}_MEDIUM`];
+  let notification = box.appendNotification(value, { label, priority });
+  await added;
+  return notification;
+}
+
+add_task(async function testStackingOrder() {
+  const tabNotificationBox = gBrowser.getNotificationBox();
+  ok(
+    gNotificationBox.stack.hasAttribute("prepend-notifications"),
+    "Browser stack will prepend"
+  );
+  ok(
+    !tabNotificationBox.stack.hasAttribute("prepend-notifications"),
+    "Tab stack will append"
+  );
+
+  let browserOne = await addNotification(
+    gNotificationBox,
+    "My first browser notification",
+    "browser-one",
+    "INFO"
+  );
+
+  let tabOne = await addNotification(
+    tabNotificationBox,
+    "My first tab notification",
+    "tab-one",
+    "CRITICAL"
+  );
+
+  let browserTwo = await addNotification(
+    gNotificationBox,
+    "My second browser notification",
+    "browser-two",
+    "CRITICAL"
+  );
+  let browserThree = await addNotification(
+    gNotificationBox,
+    "My third browser notification",
+    "browser-three",
+    "WARNING"
+  );
+
+  let tabTwo = await addNotification(
+    tabNotificationBox,
+    "My second tab notification",
+    "tab-two",
+    "INFO"
+  );
+  let tabThree = await addNotification(
+    tabNotificationBox,
+    "My third tab notification",
+    "tab-three",
+    "WARNING"
+  );
+
+  Assert.deepEqual(
+    [browserThree, browserTwo, browserOne],
+    [...gNotificationBox.stack.children],
+    "Browser notifications prepended"
+  );
+  Assert.deepEqual(
+    [tabOne, tabTwo, tabThree],
+    [...tabNotificationBox.stack.children],
+    "Tab notifications appended"
+  );
+
+  gNotificationBox.removeAllNotifications(true);
+  tabNotificationBox.removeAllNotifications(true);
+});