The Tor Browser / file revision

 /* Any copyright is dedicated to the Public Domain.

    http://creativecommons.org/publicdomain/zero/1.0/ */

 function test() {

   waitForExplicitFinish();

   let origTab = gBrowser.visibleTabs[0];

   let newTab = gBrowser.addTab();

   gBrowser.selectedTab = newTab;

   let relatedTab = gBrowser.addTab("about:blank", { ownerTab: newTab });

   // init the frame, move the owner tab to a new group and close the related

   // tab.

   TabView._initFrame(function() {

     let newTabGroupItemId = newTab._tabViewTabItem.parent.id;

     is(relatedTab.owner, newTab, "The related tab's owner is the right tab");

     // move current tab to a new group

     TabView.moveTabTo(newTab, null);

     // close the related tab

     gBrowser.removeTab(relatedTab);

     is(gBrowser.visibleTabs.length, 1, "The number of visible tabs is 1");

     is(gBrowser.visibleTabs[0], origTab, 

       "The original tab is the only visible tab");

     isnot(newTab._tabViewTabItem.parent.id, newTabGroupItemId, 

       "The moved tab item has a new group id");

     // clean up

     gBrowser.removeTab(newTab);

     finish();

   });

 }