Implementation for switching between recently used tabs using ctrl tilde or quoteleft.

chrome/browser/tabs/tab_strip_model_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/tabs/tab_strip_model.h"
 
 #include <map>
 #include <string>
 
 #include "base/file_path.h"
@@ skipping 716 matching lines @@
                                 TabContentsWrapper* contents2,
                                 TabContentsWrapper* contents3) {
   tabstrip->InsertTabContentsAt(GetInsertionIndex(tabstrip, contents1),
                                 contents1, TabStripModel::ADD_INHERIT_GROUP);
   tabstrip->InsertTabContentsAt(GetInsertionIndex(tabstrip, contents2),
                                 contents2, TabStripModel::ADD_INHERIT_GROUP);
   tabstrip->InsertTabContentsAt(GetInsertionIndex(tabstrip, contents3),
                                 contents3, TabStripModel::ADD_INHERIT_GROUP);
 }
 
+TEST_F(TabStripModelTest, TestSelectNextMRUTab) {
+  TabStripDummyDelegate delegate(NULL);
+  TabStripModel tabstrip(&delegate, profile());
+  EXPECT_TRUE(tabstrip.empty());
+
+  TabContentsWrapper* opener_contents = CreateTabContents();
+  tabstrip.AppendTabContents(opener_contents, true);
+
+  TabContentsWrapper* contents1 = CreateTabContents();
+  TabContentsWrapper* contents2 = CreateTabContents();
+  TabContentsWrapper* contents3 = CreateTabContents();
+
+  // Test LTR
+  InsertTabContentses(&tabstrip, contents1, contents2, contents3);
+  EXPECT_EQ(contents1, tabstrip.GetTabContentsAt(1));
+  EXPECT_EQ(contents2, tabstrip.GetTabContentsAt(2));
+  EXPECT_EQ(contents3, tabstrip.GetTabContentsAt(3));
+
+  EXPECT_EQ(0, tabstrip.active_index());
+  tabstrip.ActivateTabAt(1, true);
+  EXPECT_EQ(1, tabstrip.active_index());
+
+  // Next MRU Tab is tab from where we switched to tab 1 i.e tab 2
+  tabstrip.SelectNextMRUTab();
+  EXPECT_EQ(0, tabstrip.active_index());
+
+  tabstrip.CloseAllTabs();
+  EXPECT_TRUE(tabstrip.empty());
+}
+
 // Tests opening background tabs.
 TEST_F(TabStripModelTest, TestLTRInsertionOptions) {
   TabStripDummyDelegate delegate(NULL);
   TabStripModel tabstrip(&delegate, profile());
   EXPECT_TRUE(tabstrip.empty());
 
   TabContentsWrapper* opener_contents = CreateTabContents();
   tabstrip.AppendTabContents(opener_contents, true);
 
   TabContentsWrapper* contents1 = CreateTabContents();
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   ASSERT_EQ(1, observer.GetStateCount());
   MockTabStripModelObserver::State s(
       contents2, 1, MockTabStripModelObserver::SELECT);
   s.src_contents = contents2;
   s.src_index = 1;
   s.user_gesture = false;
   EXPECT_TRUE(observer.StateEquals(0, s));
   strip.RemoveObserver(&observer);
   strip.CloseAllTabs();
 }