diff -r 000000000000 -r 6474c204b198 browser/components/tabview/test/browser_tabview_undo_group.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/tabview/test/browser_tabview_undo_group.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,120 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function test() {
+  waitForExplicitFinish();
+
+  registerCleanupFunction(function() {
+    while (gBrowser.tabs[1])
+      gBrowser.removeTab(gBrowser.tabs[1]);
+    hideTabView();
+  });
+  showTabView(onTabViewWindowLoaded);
+}
+
+function onTabViewWindowLoaded() {
+  ok(TabView.isVisible(), "Tab View is visible");
+
+  let contentWindow = TabView.getContentWindow();
+
+  registerCleanupFunction(function() {
+    let groupItem = contentWindow.GroupItems.groupItem(groupItemId);
+    if (groupItem)
+      closeGroupItem(groupItem);
+  });
+
+  // create a group item
+  let groupItem = createGroupItemWithBlankTabs(window, 300, 300, 400, 1);
+  let groupItemId = groupItem.id;
+  is(groupItem.getChildren().length, 1, "The new group has a tab item");
+  // start the tests
+  waitForFocus(function() {
+    testUndoGroup(contentWindow, groupItem);
+  }, contentWindow);
+}
+
+function testUndoGroup(contentWindow, groupItem) {
+  groupItem.addSubscriber("groupHidden", function onHidden() {
+    groupItem.removeSubscriber("groupHidden", onHidden);
+
+    // check the data of the group
+    let theGroupItem = contentWindow.GroupItems.groupItem(groupItem.id);
+    ok(theGroupItem, "The group item still exists");
+    is(theGroupItem.getChildren().length, 1, 
+       "The tab item in the group still exists");
+
+    // check the visibility of the group element and undo element
+    is(theGroupItem.container.style.display, "none", 
+       "The group element is hidden");
+    ok(theGroupItem.$undoContainer, "Undo container is avaliable");
+
+    EventUtils.sendMouseEvent(
+      { type: "click" }, theGroupItem.$undoContainer[0], contentWindow);
+  });
+
+  groupItem.addSubscriber("groupShown", function onShown() {
+    groupItem.removeSubscriber("groupShown", onShown);
+
+    // check the data of the group
+    let theGroupItem = contentWindow.GroupItems.groupItem(groupItem.id);
+    ok(theGroupItem, "The group item still exists");
+    is(theGroupItem.getChildren().length, 1, 
+       "The tab item in the group still exists");
+
+    // check the visibility of the group element and undo element
+    is(theGroupItem.container.style.display, "", "The group element is visible");
+    ok(!theGroupItem.$undoContainer, "Undo container is not avaliable");
+    
+    // start the next test
+    testCloseUndoGroup(contentWindow, groupItem);
+  });
+
+  let closeButton = groupItem.container.getElementsByClassName("close");
+  ok(closeButton[0], "Group item close button exists");
+  EventUtils.sendMouseEvent({ type: "click" }, closeButton[0], contentWindow);
+}
+
+function testCloseUndoGroup(contentWindow, groupItem) {
+  groupItem.addSubscriber("groupHidden", function onHidden() {
+    groupItem.removeSubscriber("groupHidden", onHidden);
+
+    // check the data of the group
+    let theGroupItem = contentWindow.GroupItems.groupItem(groupItem.id);
+    ok(theGroupItem, "The group item still exists");
+    is(theGroupItem.getChildren().length, 1, 
+       "The tab item in the group still exists");
+
+    // check the visibility of the group element and undo element
+    is(theGroupItem.container.style.display, "none", 
+       "The group element is hidden");
+    ok(theGroupItem.$undoContainer, "Undo container is avaliable");
+
+    // click on close
+    let closeButton = theGroupItem.$undoContainer.find(".close");
+    EventUtils.sendMouseEvent(
+      { type: "click" }, closeButton[0], contentWindow);
+  });
+
+  groupItem.addSubscriber("close", function onClose() {
+    groupItem.removeSubscriber("close", onClose);
+
+    let theGroupItem = contentWindow.GroupItems.groupItem(groupItem.id);
+    ok(!theGroupItem, "The group item doesn't exists");
+
+    // after the last selected tabitem is closed, there would be not active
+    // tabitem on the UI so we set the active tabitem before toggling the 
+    // visibility of tabview
+    let tabItems = contentWindow.TabItems.getItems();
+    ok(tabItems[0], "A tab item exists");
+    contentWindow.UI.setActive(tabItems[0]);
+
+    hideTabView(function() {
+      ok(!TabView.isVisible(), "Tab View is hidden");
+      finish();
+    });
+  });
+
+  let closeButton = groupItem.container.getElementsByClassName("close");
+  ok(closeButton[0], "Group item close button exists");
+  EventUtils.sendMouseEvent({ type: "click" }, closeButton[0], contentWindow);
+}