Last_n: Delete previously saved snapshot when navigating.

chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc

 // Copyright 2016 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/android/offline_pages/recent_tab_helper.h"
 
 #include <memory>
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/string16.h"
@@ skipping 357 matching lines @@
   ASSERT_EQ(0U, GetAllPages().size());
 
   // But the following download request should work normally
   recent_tab_helper()->ObserveAndDownloadCurrentPage(NewDownloadClientId(),
                                                      123L);
   RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   ASSERT_EQ(1U, GetAllPages().size());
 }
 
-// Checks that last_n will not save a snapshot if the tab while the tab is
-// presented as a custom tab. Download requests should be unaffected though.
+// Checks that last_n will not save a snapshot while the tab is being presented
+// as a custom tab. Download requests should be unaffected though.
 TEST_F(RecentTabHelperTest, LastNWontSaveCustomTab) {
   // Simulates the tab running as a custom tab.
   default_test_delegate()->set_is_custom_tab(true);
 
   // Navigate and finish loading then hide the tab. Nothing should be saved.
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
@@ skipping 103 matching lines @@
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
   EXPECT_EQ(kTestPageUrl, GetAllPages()[0].url);
   int64_t first_offline_id = GetAllPages()[0].offline_id;
 
-  // Navigate with the same URL until the page is minimally loaded then hide the
-  // tab. The previous snapshot should be removed and a new one taken.
+  // Reload the same URL until the page is minimally loaded. The previous
+  // snapshot should have been removed.
   NavigateAndCommitTyped(kTestPageUrl);
   recent_tab_helper()->DocumentAvailableInMainFrame();
   FastForwardSnapshotController();
   EXPECT_EQ(1U, page_added_count());
-  EXPECT_EQ(0U, model_removed_count());
-  ASSERT_EQ(1U, GetAllPages().size());
+  EXPECT_EQ(1U, model_removed_count());
+  ASSERT_EQ(0U, GetAllPages().size());
 
+  // Hide the tab and a new snapshot should be taken.
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(2U, page_added_count());
   EXPECT_EQ(1U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
   EXPECT_EQ(kTestPageUrl, GetAllPages()[0].url);
   EXPECT_NE(first_offline_id, GetAllPages()[0].offline_id);
 }
 
 // Triggers two last_n captures for two different page loads of the same URL
@@ skipping 36 matching lines @@
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
   EXPECT_EQ(kTestPageUrl, GetAllPages()[0].url);
 
-  // Fully load the second URL then hide the tab and check for a single snapshot
-  // of the new page.
+  // Fully load the second URL. The previous snapshot should have been deleted.
   NavigateAndCommitTyped(kTestPageUrlOther);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   EXPECT_EQ(1U, page_added_count());
-  EXPECT_EQ(0U, model_removed_count());
-  ASSERT_EQ(1U, GetAllPages().size());
+  EXPECT_EQ(1U, model_removed_count());
+  ASSERT_EQ(0U, GetAllPages().size());
 
+  // Then hide the tab and check for a single snapshot of the new page.
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(2U, page_added_count());
   EXPECT_EQ(1U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
   EXPECT_EQ(kTestPageUrlOther, GetAllPages()[0].url);
 }
 
 // Fully loads a page where last_n captures two snapshots. Then triggers two
 // snapshot requests by downloads. Should end up with three offline pages: one
@@ skipping 137 matching lines @@
   EXPECT_EQ(153L, page.offline_id);
 
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   EXPECT_EQ(2U, page_added_count());
   EXPECT_EQ(1U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
 }
 
 // Simulates a download request to offline the current page made after loading
-// is completed. Should end up with one offline pages.
+// is completed. Should end up with one offline page.
 TEST_F(RecentTabHelperTest, DownloadRequestAfterFullyLoad) {
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   EXPECT_TRUE(model()->is_loaded());
   ASSERT_EQ(0U, GetAllPages().size());
 
   const ClientId client_id = NewDownloadClientId();
   recent_tab_helper()->ObserveAndDownloadCurrentPage(client_id, 153L);
   RunUntilIdle();
@@ skipping 145 matching lines @@
 // Tests that a page reloaded is tracked as an actual load and properly saved.
 TEST_F(RecentTabHelperTest, ReloadIsTrackedAsNavigationAndSavedOnlyUponLoad) {
   // Navigates and load fully then hide the tab so that a snapshot is created.
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   ASSERT_EQ(1U, GetAllPages().size());
 
-  // Starts a reload and hides the tab. No new snapshot should be saved.
+  // Starts a reload and hides the tab before it minimally load. The previous
+  // snapshot should be removed.
   controller().Reload(content::ReloadType::NORMAL, false);
   content::WebContentsTester* web_contents_tester =
       content::WebContentsTester::For(web_contents());
   web_contents_tester->CommitPendingNavigation();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
-  EXPECT_EQ(0U, model_removed_count());
-  ASSERT_EQ(1U, GetAllPages().size());
+  EXPECT_EQ(1U, model_removed_count());
+  ASSERT_EQ(0U, GetAllPages().size());
 
   // Finish loading and hide the tab. A new snapshot should be created.
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(2U, page_added_count());
   EXPECT_EQ(1U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
 }
@@ skipping 19 matching lines @@
   // moment a snapshot should be created.
   recent_tab_helper()->WasShown();
   recent_tab_helper()->WasHidden();
   RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
 }
 
 }  // namespace offline_pages