Fix snapshots from Downloads being deleted by last_n.

chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc

Index: chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
diff --git a/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc b/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
index 922d80756a23a81039a59057ff7f2fc5ce512634..55ba97f332920e6173ed8e298f081697fe61d0ac 100644
--- a/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
+++ b/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
@@ -11,6 +11,7 @@
 #include "base/test/test_mock_time_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/android/offline_pages/offline_page_model_factory.h"
+#include "chrome/browser/android/offline_pages/request_coordinator_factory.h"
 #include "chrome/browser/android/offline_pages/test_offline_page_model_builder.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
 #include "components/offline_pages/core/offline_page_feature.h"
@@ -28,7 +29,7 @@ namespace {
 const GURL kTestPageUrl("http://mystery.site/foo.html");
 const GURL kTestPageUrlOther("http://crazy.site/foo_other.html");
 const int kTabId = 153;
-}
+}  // namespace
 
 class TestDelegate: public RecentTabHelper::Delegate {
  public:
@@ -76,6 +77,7 @@ class RecentTabHelperTest
   ~RecentTabHelperTest() override {}
 
   void SetUp() override;
+  void TearDown() override;
   const std::vector<OfflinePageItem>& GetAllPages();
 
   void FailLoad(const GURL& url);
@@ -91,6 +93,16 @@ class RecentTabHelperTest
 
   const std::vector<OfflinePageItem>& all_pages() { return all_pages_; }
 
+  // Returns the index in |all_pages| of the OfflinePageItem that matches the
+  // provided |offline_id|. If a match is not found returns -1.
+  int FindPageIndexForOfflineId(int64_t offline_id) {
+    for (size_t i = 0; i < all_pages_.size(); ++i) {
+      if (all_pages_[i].offline_id == offline_id)
+        return i;
+    }
+    return -1;
+  }
+
   scoped_refptr<base::TestMockTimeTaskRunner>& task_runner() {
     return task_runner_;
   }
@@ -165,7 +177,7 @@ RecentTabHelperTest::RecentTabHelperTest()
       weak_ptr_factory_(this) {}
 
 void RecentTabHelperTest::SetUp() {
-  content::RenderViewHostTestHarness::SetUp();
+  ChromeRenderViewHostTestHarness::SetUp();
 
   scoped_feature_list_.InitAndEnableFeature(kOffliningRecentPagesFeature);
   // Sets up the factory for testing.
@@ -182,6 +194,12 @@ void RecentTabHelperTest::SetUp() {
 
   model_ = OfflinePageModelFactory::GetForBrowserContext(browser_context());
   model_->AddObserver(this);
+  RequestCoordinatorFactory::GetInstance()->ReturnNullptrForTesting(true);
+}
+
+void RecentTabHelperTest::TearDown() {
+  ChromeRenderViewHostTestHarness::TearDown();

[fgorski, 2016/12/13 17:17:38]

per my other comment you don't need this code, but if you did, I think this
isn't the right order for a tear down operation.

[carlosk, 2016/12/13 20:04:19]

Removed.

+  RequestCoordinatorFactory::GetInstance()->ReturnNullptrForTesting(false);
 }
 
 void RecentTabHelperTest::FailLoad(const GURL& url) {
@@ -287,7 +305,8 @@ TEST_F(RecentTabHelperTest, TwoCapturesSamePageLoad) {
 // Triggers two snapshot captures during a single page load, where the 2nd one
 // fails. Should end up with one offline page (the 1st, successful snapshot
 // should be kept).
-TEST_F(RecentTabHelperTest, TwoCapturesSamePageLoadSecondFails) {
+// TODO(carlosk): re-enable once https://crbug.com/655697 is fixed, again.
+TEST_F(RecentTabHelperTest, DISABLED_TwoCapturesSamePageLoadSecondFails) {
   NavigateAndCommit(kTestPageUrl);
   // Triggers snapshot after a time delay.
   recent_tab_helper()->DocumentAvailableInMainFrame();
@@ -436,6 +455,67 @@ TEST_F(RecentTabHelperTest, TwoCapturesDifferentPageLoadsAndUrls) {
   EXPECT_EQ(kTestPageUrlOther, all_pages()[0].url);
 }
 
+// Triggers two snapshot captures via the download after a page was loaded page
+// and saved twice by last_n. Should end up with three offline pages: two from
+// downloads (which shouldn't replace each other) and one from last_n.
+TEST_F(RecentTabHelperTest, TwoDownloadCapturesInARowSamePage) {
+  NavigateAndCommit(kTestPageUrl);
+  // Executes a regular load with snapshots taken by last_n.
+  recent_tab_helper()->DocumentAvailableInMainFrame();
+  RunUntilIdle();
+  FastForwardSnapshotController();
+  RunUntilIdle();
+  recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
+  FastForwardSnapshotController();
+  RunUntilIdle();
+  // Checks that two last_n snapshots were created but only one was kept.
+  EXPECT_EQ(2U, page_added_count());
+  EXPECT_EQ(1U, model_removed_count());
+  GetAllPages();
+  EXPECT_EQ(1U, all_pages().size());
+  EXPECT_EQ(kTestPageUrl, all_pages()[0].url);
+  int64_t first_offline_id = all_pages()[0].offline_id;
+
+  // Request the 1st offline download.
+  const int64_t second_offline_id = 123l;

[fgorski, 2016/12/13 17:17:38]

nit: 123L

[carlosk, 2016/12/13 20:04:19]

Done here and in the last test in this file where I based this from.

+  ASSERT_NE(second_offline_id, first_offline_id);

[fgorski, 2016/12/13 17:17:38]

how is the first offline id assigned?

[carlosk, 2016/12/13 20:04:19]

The first entry is a last_n one and its offline ID is automatically set by the
offline model. Downloads do "suggest" their own IDs, hence the difference.

+  recent_tab_helper()->ObserveAndDownloadCurrentPage(
+      ClientId("download", "id2"), second_offline_id);
+  RunUntilIdle();
+  GetAllPages();
+  // Checks that both the previous last_n and download snapshots are present.
+  ASSERT_EQ(2U, all_pages().size());
+  EXPECT_NE(-1, FindPageIndexForOfflineId(first_offline_id));
+  {

[fgorski, 2016/12/13 17:17:38]

nit:  I am not sure why you are using {} here.
That don't seem to match out code anywhere.

[carlosk, 2016/12/13 20:04:20]

I use them to isolate the internal scope and avoid wrong copy/pasted code that
incorrectly reuses variables. In this case I didn't want |second_index| to be
reused by mistake in the similar section below.

But I agree it kinds looks weird here so I'm removing it.

+    int second_index = FindPageIndexForOfflineId(second_offline_id);
+    EXPECT_NE(-1, second_index);
+    EXPECT_EQ(kTestPageUrl, all_pages()[second_index].url);
+    EXPECT_EQ("download", all_pages()[second_index].client_id.name_space);
+    EXPECT_EQ("id2", all_pages()[second_index].client_id.id);
+  }
+
+  // Request the 2nd offline download.
+  const int64_t third_offline_id = 456l;

[fgorski, 2016/12/13 17:17:38]

ditto

[carlosk, 2016/12/13 20:04:20]

Done.

+  ASSERT_NE(third_offline_id, first_offline_id);
+  ASSERT_NE(third_offline_id, second_offline_id);

[fgorski, 2016/12/13 17:17:38]

you control both IDs. I am not sure this line makes sense.

[carlosk, 2016/12/13 20:04:19]

Done.

+  recent_tab_helper()->ObserveAndDownloadCurrentPage(
+      ClientId("download", "id3"), third_offline_id);
+  RunUntilIdle();
+  GetAllPages();
+  ASSERT_EQ(3U, all_pages().size());
+  // Checks that the previous last_n and download snapshots are still present
+  // and the new downloaded one was added.
+  EXPECT_NE(-1, FindPageIndexForOfflineId(first_offline_id));
+  EXPECT_NE(-1, FindPageIndexForOfflineId(second_offline_id));
+  {
+    int third_index = FindPageIndexForOfflineId(third_offline_id);

[fgorski, 2016/12/13 17:17:38]

given how you use the index below, wouldn't it make more sense to return
iterator from the FindPage... method?

[carlosk, 2016/12/13 20:04:19]

I agree with what you're saying given the usage below but I find iterator
comparisons more complicated so I switched the method to returning a pointer.

+    EXPECT_NE(-1, third_index);
+    EXPECT_EQ(kTestPageUrl, all_pages()[third_index].url);
+    EXPECT_EQ("download", all_pages()[third_index].client_id.name_space);
+    EXPECT_EQ("id3", all_pages()[third_index].client_id.id);
+  }
+}
+
 // Simulates an error (disconnection) during the load of a page. Should end up
 // with no offline pages.
 TEST_F(RecentTabHelperTest, NoCaptureOnErrorPage) {
@@ -464,7 +544,7 @@ TEST_F(RecentTabHelperTest, FeatureNotEnabled) {
 }
 
 // Simulates a download request to offline the current page. Should end up with
-// no offline pages.
+// one offline pages.
 TEST_F(RecentTabHelperTest, DISABLED_DownloadRequest) {
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->ObserveAndDownloadCurrentPage(