[Sync] Restore previous session if no tabbed windows present

components/sync_sessions/synced_session_tracker_unittest.cc

 // Copyright 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 "components/sync_sessions/synced_session_tracker.h"
 
 #include "base/rand_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/sessions/core/serialized_navigation_entry_test_helper.h"
@@ skipping 43 matching lines @@
 TEST_F(SyncedSessionTrackerTest, GetTabUnmapped) {
   sessions::SessionTab* tab = GetTracker()->GetTab(kTag, 0);
   ASSERT_EQ(tab, GetTracker()->GetTab(kTag, 0));
   // Should clean up memory on its own.
 }
 
 TEST_F(SyncedSessionTrackerTest, PutWindowInSession) {
   GetTracker()->PutWindowInSession(kTag, 0);
   SyncedSession* session = GetTracker()->GetSession(kTag);
   ASSERT_EQ(1U, session->windows.size());
+
+  // Doing it again should have no effect.
+  GetTracker()->PutWindowInSession(kTag, 0);
+  ASSERT_EQ(1U, session->windows.size());
   // Should clean up memory on its own.
 }
 
 TEST_F(SyncedSessionTrackerTest, PutTabInWindow) {
   GetTracker()->PutWindowInSession(kTag, 10);
   GetTracker()->PutTabInWindow(kTag, 10, 15);  // win id 10, tab id 15
   SyncedSession* session = GetTracker()->GetSession(kTag);
   ASSERT_EQ(1U, session->windows.size());
   ASSERT_EQ(1U, session->windows[10]->wrapped_window.tabs.size());
   ASSERT_EQ(GetTracker()->GetTab(kTag, 15),
@@ skipping 243 matching lines @@
   GetTracker()->ResetSessionTracking(kTag);
   GetTracker()->PutWindowInSession(kTag, 0);
   GetTracker()->PutTabInWindow(kTag, 0, 0);
   // Tab 1 is closed.
   GetTracker()->PutTabInWindow(kTag, 0, 2);  // No longer unmapped.
   // Tab 3 was unmapped and does not get used.
   GetTracker()->PutTabInWindow(kTag, 0, 4);  // Moved from window 1.
   // Window 1 was closed, along with tab 5.
   GetTracker()->PutTabInWindow(kTag, 0, 6);  // No longer unmapped.
   // Session 2 should not be affected.
-  GetTracker()->CleanupForeignSession(kTag);
+  GetTracker()->CleanupSession(kTag);
 
   // Verify that only those parts of the session not owned have been removed.
   ASSERT_EQ(1U, session1->windows.size());
   ASSERT_EQ(4U, session1->windows[0]->wrapped_window.tabs.size());
   ASSERT_EQ(1U, session2->windows.size());
   ASSERT_EQ(1U, session2->windows[2]->wrapped_window.tabs.size());
   ASSERT_EQ(2U, GetTracker()->num_synced_sessions());
   ASSERT_EQ(4U, GetTracker()->num_synced_tabs(kTag));
   ASSERT_EQ(1U, GetTracker()->num_synced_tabs(kTag2));
 
@@ skipping 215 matching lines @@
   // Now that it's been mapped, it should be accessible both via the
   // GetSession as well as GetTab.
   SyncedSession* session = GetTracker()->GetSession(kTag);
   ASSERT_EQ(GetTracker()->GetTab(kTag, kTab2),
             session->windows[kWindow1]->wrapped_window.tabs[0].get());
   ASSERT_EQ(session->tab_node_ids.size(),
             session->tab_node_ids.count(kTabNode));
   ASSERT_EQ(1U, GetTabNodePool()->Capacity());
 }
 
+TEST_F(SyncedSessionTrackerTest, ReassociateTabMapMismatch) {
+  std::set<int> free_node_ids;
+
+  // First create the old tab in an unmapped state.
+  GetTracker()->SetLocalSessionTag(kTag);
+  EXPECT_FALSE(GetTracker()->IsLocalTabNodeAssociated(kTabNode));
+  GetTracker()->ReassociateLocalTab(kTabNode, kTab1);
+  EXPECT_TRUE(GetTracker()->IsLocalTabNodeAssociated(kTabNode));
+  EXPECT_TRUE(GetTracker()->IsTabUnmappedForTesting(kTab1));
+
+  // Map an unseen tab to a window, then reassociate the existing tab to the
+  // mapped tab id.
+  GetTracker()->ResetSessionTracking(kTag);
+  EXPECT_TRUE(GetTracker()->IsLocalTabNodeAssociated(kTabNode));
+  GetTracker()->PutWindowInSession(kTag, kWindow1);
+  GetTracker()->PutTabInWindow(kTag, kWindow1, kTab2);
+  GetTracker()->CleanupLocalTabs(&free_node_ids);
+  EXPECT_FALSE(GetTracker()->IsTabUnmappedForTesting(kTab1));
+  EXPECT_FALSE(GetTracker()->IsTabUnmappedForTesting(kTab2));
+  GetTracker()->ReassociateLocalTab(kTabNode, kTab2);
+  EXPECT_TRUE(free_node_ids.empty());
+  EXPECT_FALSE(GetTracker()->IsTabUnmappedForTesting(kTab1));
+  EXPECT_FALSE(GetTracker()->IsTabUnmappedForTesting(kTab2));
+
+  // Now that it's been mapped, it should be accessible both via the
+  // GetSession as well as GetTab.
+  SyncedSession* session = GetTracker()->GetSession(kTag);
+  ASSERT_EQ(GetTracker()->GetTab(kTag, kTab2),
+            session->windows[kWindow1]->wrapped_window.tabs[0].get());
+  ASSERT_EQ(session->tab_node_ids.size(),
+            session->tab_node_ids.count(kTabNode));
+  ASSERT_EQ(1U, GetTabNodePool()->Capacity());
+}
+
 }  // namespace sync_sessions