Seculative resource prefetching for URLs CL.

chrome/browser/predictors/resource_prefetch_predictor_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 "base/memory/ref_counted.h"
+#include "base/message_loop.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/time.h"
+#include "chrome/browser/history/history.h"
+#include "chrome/browser/history/history_types.h"
+#include "chrome/browser/history/in_memory_database.h"
+#include "chrome/browser/history/url_database.h"
+#include "chrome/browser/predictors/resource_prefetch_predictor.h"
+#include "chrome/browser/predictors/resource_prefetch_predictor_tables.h"
+#include "chrome/test/base/testing_profile.h"
+#include "content/public/test/test_browser_thread.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+using testing::ContainerEq;
+using testing::Pointee;
+using testing::SetArgPointee;
+
+namespace predictors {
+
+typedef ResourcePrefetchPredictor::URLRequestSummary URLRequestSummary;
+typedef ResourcePrefetchPredictorTables::UrlTableRow UrlTableRow;
+typedef ResourcePrefetchPredictorTables::UrlTableRows UrlTableRows;
+
+class MockResourcePrefetchPredictorTables
+    : public ResourcePrefetchPredictorTables {
+ public:
+  MockResourcePrefetchPredictorTables() { }
+
+  MOCK_METHOD1(GetAllRows, void(std::vector<UrlTableRow>* url_row_buffer));
+  MOCK_METHOD2(UpdateRowsForUrl, void(const GURL& main_page_url,
+                                      const UrlTableRows& row_buffer));
+  MOCK_METHOD1(DeleteRowsForUrls, void(const std::vector<GURL>& urls));
+  MOCK_METHOD0(DeleteAllRows, void());
+
+ private:
+  ~MockResourcePrefetchPredictorTables() { }
+};
+
+class ResourcePrefetchPredictorTest : public testing::Test {
+ public:
+  ResourcePrefetchPredictorTest();
+  ~ResourcePrefetchPredictorTest();
+  void SetUp() OVERRIDE;
+  void TearDown() OVERRIDE;
+
+ protected:
+  void AddUrlToHistory(const std::string& url,
+                       int visit_count,
+                       time_t last_visit) {
+    history::URLRow row = history::URLRow(GURL(url));
+    row.set_visit_count(visit_count);
+    row.set_last_visit(base::Time::FromTimeT(last_visit));
+    url_db_->AddURL(row);
+  }
+
+  NavigationID CreateNavigationID(int process_id,
+                                  int render_view_id,
+                                  const std::string& main_frame_url) {
+    NavigationID navigation_id;
+    navigation_id.render_process_id = process_id;
+    navigation_id.render_view_id = render_view_id;
+    navigation_id.main_frame_url = GURL(main_frame_url);
+    navigation_id.creation_time = base::TimeTicks::Now();
+    return navigation_id;
+  }
+
+  ResourcePrefetchPredictor::URLRequestSummary CreateURLRequestSummary(
+      int process_id,
+      int render_view_id,
+      const std::string& main_frame_url,
+      const std::string& resource_url,
+      ResourceType::Type resource_type,
+      const std::string& mime_type,
+      bool was_cached) {
+    ResourcePrefetchPredictor::URLRequestSummary summary;
+    summary.navigation_id = CreateNavigationID(process_id, render_view_id,
+                                               main_frame_url);
+    summary.resource_url = GURL(resource_url);
+    summary.resource_type = resource_type;
+    summary.mime_type = mime_type;
+    summary.was_cached = was_cached;
+    return summary;
+  }
+
+  bool URLRequestSummaryAreEqual(const URLRequestSummary& lhs,
+                                 const URLRequestSummary& rhs) {
+    return lhs.navigation_id == rhs.navigation_id &&
+        lhs.resource_url == rhs.resource_url &&
+        lhs.resource_type == rhs.resource_type &&
+        lhs.mime_type == rhs.mime_type &&
+        lhs.was_cached == rhs.was_cached;
+  }
+
+  void ResetPredictor() {
+    ResourcePrefetchPredictor::Config config;
+    config.max_urls_to_track = 3;
+    config.min_url_visit_count = 2;
+    config.max_resources_per_entry = 4;
+    config.max_consecutive_misses = 2;
+    predictor_.reset(new ResourcePrefetchPredictor(config, &profile_));
+    predictor_->SetTablesForTesting(mock_tables_);
+  }
+
+  MessageLoop loop_;
+  content::TestBrowserThread ui_thread_;
+  content::TestBrowserThread db_thread_;
+  TestingProfile profile_;
+
+  scoped_ptr<ResourcePrefetchPredictor> predictor_;
+  scoped_refptr<MockResourcePrefetchPredictorTables> mock_tables_;
+  UrlTableRows test_url_rows_;
+  history::URLDatabase* url_db_;
+};
+
+ResourcePrefetchPredictorTest::ResourcePrefetchPredictorTest()
+    : loop_(MessageLoop::TYPE_DEFAULT),
+      ui_thread_(content::BrowserThread::UI, &loop_),
+      db_thread_(content::BrowserThread::DB, &loop_),
+      predictor_(NULL),
+      mock_tables_(new MockResourcePrefetchPredictorTables()) {
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.google.com",
+      "http://google.com/style1.css",
+      ResourceType::STYLESHEET,
+      3, 2, 1, 1.0));
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.google.com",
+      "http://google.com/script3.js",
+      ResourceType::SCRIPT,
+      4, 0, 1, 2.1));
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.google.com",
+      "http://google.com/script4.js",
+      ResourceType::SCRIPT,
+      11, 0, 0, 2.1));
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.google.com",
+      "http://google.com/image1.png",
+      ResourceType::IMAGE,
+      6, 3, 0, 2.2));
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.google.com",
+      "http://google.com/a.font",
+      ResourceType::LAST_TYPE,
+      2, 0, 0, 5.1));
+
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.reddit.com",
+      "http://reddit-resource.com/script1.js",
+      ResourceType::SCRIPT,
+      4, 0, 1, 1.0));
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.reddit.com",
+      "http://reddit-resource.com/script2.js",
+      ResourceType::SCRIPT,
+      2, 0, 0, 2.1));
+
+  test_url_rows_.push_back(UrlTableRow(
+      "http://www.yahoo.com",
+      "http://google.com/image.png",
+      ResourceType::IMAGE,
+      20, 1, 0, 10.0));
+}
+
+ResourcePrefetchPredictorTest::~ResourcePrefetchPredictorTest() {
+}
+
+void ResourcePrefetchPredictorTest::SetUp() {
+  profile_.CreateHistoryService(true, false);
+  profile_.BlockUntilHistoryProcessesPendingRequests();
+  EXPECT_TRUE(profile_.GetHistoryService(Profile::EXPLICIT_ACCESS));
+  url_db_ = profile_.GetHistoryService(
+      Profile::EXPLICIT_ACCESS)->InMemoryDatabase();
+
+  // Initialize the predictor with empty data.
+  ResetPredictor();
+  EXPECT_EQ(predictor_->initialization_state_,
+            ResourcePrefetchPredictor::NOT_INITIALIZED);
+  EXPECT_CALL(*mock_tables_, GetAllRows(Pointee(ContainerEq(UrlTableRows()))));
+  predictor_->LazilyInitialize();
+  profile_.BlockUntilHistoryProcessesPendingRequests();
+  EXPECT_TRUE(predictor_->inflight_navigations_.empty());
+  EXPECT_EQ(predictor_->initialization_state_,
+            ResourcePrefetchPredictor::INITIALIZED);
+}
+
+void ResourcePrefetchPredictorTest::TearDown() {
+  predictor_.reset(NULL);
+  profile_.DestroyHistoryService();
+}
+
+TEST_F(ResourcePrefetchPredictorTest, LazilyInitializeEmpty) {
+  // Tests that the predictor initializes correctly without any data.
+  EXPECT_TRUE(predictor_->url_table_cache_.empty());
+}
+
+TEST_F(ResourcePrefetchPredictorTest, LazilyInitializeWithData) {
+  // Tests that the history and the db tables data are loaded correctly.
+  AddUrlToHistory("http://www.google.com", 4, 12345);
+  AddUrlToHistory("http://www.yahoo.com", 2, 12346);
+
+  EXPECT_CALL(*mock_tables_, GetAllRows(Pointee(ContainerEq(UrlTableRows()))))
+      .WillOnce(SetArgPointee<0>(test_url_rows_));
+
+  std::vector<GURL> urls_to_delete;
+  urls_to_delete.push_back(GURL("http://www.reddit.com"));
+  EXPECT_CALL(*mock_tables_, DeleteRowsForUrls(ContainerEq(urls_to_delete)));
+
+  ResetPredictor();
+  predictor_->LazilyInitialize();
+  loop_.RunAllPending();
+
+  // Test that the internal variables correctly initialized.
+  EXPECT_EQ(predictor_->initialization_state_,
+            ResourcePrefetchPredictor::INITIALIZED);
+  EXPECT_TRUE(predictor_->inflight_navigations_.empty());
+  EXPECT_EQ(2, static_cast<int>(predictor_->url_table_cache_.size()));
+
+  UrlTableRows google_rows(test_url_rows_.begin(),
+                           test_url_rows_.begin() + 5);
+  std::sort(google_rows.begin(), google_rows.end(),
+            ResourcePrefetchPredictorTables::UrlTableRowSorter());
+  EXPECT_EQ(predictor_->url_table_cache_[GURL("http://www.google.com")].rows,
+            google_rows);
+  EXPECT_EQ(
+      predictor_->url_table_cache_[GURL("http://www.google.com")].last_visit,
+      base::Time::FromTimeT(12345));
+
+  UrlTableRows yahoo_rows(test_url_rows_.begin() + 7,
+                          test_url_rows_.begin() + 8);
+  EXPECT_EQ(predictor_->url_table_cache_[GURL("http://www.yahoo.com")].rows,
+            yahoo_rows);
+  EXPECT_EQ(
+      predictor_->url_table_cache_[GURL("http://www.yahoo.com")].last_visit,
+      base::Time::FromTimeT(12346));
+}
+
+TEST_F(ResourcePrefetchPredictorTest, NavigationNotRecorded) {
+  // Single navigation but history count is low, so should not record.
+  AddUrlToHistory("http://www.google.com", 1, 12345);
+
+  URLRequestSummary main_frame = CreateURLRequestSummary(
+      1, 1, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  predictor_->RecordURLRequest(main_frame);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  // Now add a few subresources.
+  URLRequestSummary resource1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/style1.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->RecordUrlResponse(resource1);
+  URLRequestSummary resource2 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script1.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->RecordUrlResponse(resource2);
+  URLRequestSummary resource3 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script2.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->RecordUrlResponse(resource3);
+  predictor_->OnNavigationComplete(main_frame.navigation_id);
+}
+
+TEST_F(ResourcePrefetchPredictorTest, NavigationUrlNotInDB) {
+  // Single navigation that will be recorded. Will check for duplicate
+  // resources and also for number of resources saved.
+  AddUrlToHistory("http://www.google.com", 4, 12345);
+
+  URLRequestSummary main_frame = CreateURLRequestSummary(
+      1, 1, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  predictor_->RecordURLRequest(main_frame);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  URLRequestSummary resource1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/style1.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->RecordUrlResponse(resource1);
+  URLRequestSummary resource2 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script1.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->RecordUrlResponse(resource2);
+  URLRequestSummary resource3 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script2.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->RecordUrlResponse(resource3);
+  URLRequestSummary resource4 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script1.js",
+      ResourceType::SCRIPT, "text/javascript", true);
+  predictor_->RecordUrlResponse(resource4);
+  URLRequestSummary resource5 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/image1.png",
+      ResourceType::IMAGE, "image/png", false);
+  predictor_->RecordUrlResponse(resource5);
+  URLRequestSummary resource6 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/image2.png",
+      ResourceType::IMAGE, "image/png", false);
+  predictor_->RecordUrlResponse(resource6);
+  URLRequestSummary resource7 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/style2.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->OnSubresourceLoadedFromMemory(
+      resource7.navigation_id,
+      resource7.resource_url,
+      resource7.mime_type,
+      resource7.resource_type);
+
+  UrlTableRows db_rows;
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/style1.css",
+      ResourceType::STYLESHEET, 1, 0, 0, 1.0));
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/script1.js",
+      ResourceType::SCRIPT, 1, 0, 0, 2.0));
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/script2.js",
+      ResourceType::SCRIPT, 1, 0, 0, 3.0));
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/style2.css",
+      ResourceType::STYLESHEET, 1, 0, 0, 7.0));
+  EXPECT_CALL(*mock_tables_,
+              UpdateRowsForUrl(GURL("http://www.google.com"),
+                               ContainerEq(db_rows)));
+
+  predictor_->OnNavigationComplete(main_frame.navigation_id);
+}
+
+TEST_F(ResourcePrefetchPredictorTest, NavigationUrlInDB) {
+  // Tests that navigation is recoreded correctly for URL already present in
+  // the database cache.
+  AddUrlToHistory("http://www.google.com", 4, 12345);
+
+  EXPECT_CALL(*mock_tables_, GetAllRows(Pointee(ContainerEq(UrlTableRows()))))
+      .WillOnce(SetArgPointee<0>(test_url_rows_));
+
+  std::vector<GURL> urls_to_delete;
+  urls_to_delete.push_back(GURL("http://www.reddit.com"));
+  urls_to_delete.push_back(GURL("http://www.yahoo.com"));
+  EXPECT_CALL(*mock_tables_, DeleteRowsForUrls(ContainerEq(urls_to_delete)));
+
+  ResetPredictor();
+  predictor_->LazilyInitialize();
+  loop_.RunAllPending();
+
+  URLRequestSummary main_frame = CreateURLRequestSummary(
+      1, 1, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  predictor_->RecordURLRequest(main_frame);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  URLRequestSummary resource1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/style1.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->RecordUrlResponse(resource1);
+  URLRequestSummary resource2 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script1.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->RecordUrlResponse(resource2);
+  URLRequestSummary resource3 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script2.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->RecordUrlResponse(resource3);
+  URLRequestSummary resource4 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script1.js",
+      ResourceType::SCRIPT, "text/javascript", true);
+  predictor_->RecordUrlResponse(resource4);
+  URLRequestSummary resource5 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/image1.png",
+      ResourceType::IMAGE, "image/png", false);
+  predictor_->RecordUrlResponse(resource5);
+  URLRequestSummary resource6 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/image2.png",
+      ResourceType::IMAGE, "image/png", false);
+  predictor_->RecordUrlResponse(resource6);
+  URLRequestSummary resource7 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/style2.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->OnSubresourceLoadedFromMemory(
+      resource7.navigation_id,
+      resource7.resource_url,
+      resource7.mime_type,
+      resource7.resource_type);
+
+  UrlTableRows db_rows;
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/style1.css",
+      ResourceType::STYLESHEET, 4, 2, 0, 1.0));
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/script1.js",
+      ResourceType::SCRIPT, 1, 0, 0, 2.0));
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/script4.js",
+      ResourceType::SCRIPT, 11, 1, 1, 2.1));
+  db_rows.push_back(UrlTableRow(
+      "http://www.google.com", "http://google.com/script2.js",
+      ResourceType::SCRIPT, 1, 0, 0, 3.0));
+  EXPECT_CALL(*mock_tables_,
+              UpdateRowsForUrl(GURL("http://www.google.com"),
+                               ContainerEq(db_rows)));
+
+  predictor_->OnNavigationComplete(main_frame.navigation_id);
+}
+
+TEST_F(ResourcePrefetchPredictorTest, NavigationUrlNotInDBAndDBFull) {
+  // Tests that a URL is deleted before another is added if the cache is full.
+  AddUrlToHistory("http://www.google.com", 4, 12345);
+  AddUrlToHistory("http://www.reddit.com", 4, 12340);  // Should be deleted.
+  AddUrlToHistory("http://www.yahoo.com", 4, 12350);
+  AddUrlToHistory("http://www.nike.com", 4, 10000);
+
+  EXPECT_CALL(*mock_tables_, GetAllRows(Pointee(ContainerEq(UrlTableRows()))))
+      .WillOnce(SetArgPointee<0>(test_url_rows_));
+
+  ResetPredictor();
+  predictor_->LazilyInitialize();
+  loop_.RunAllPending();
+  EXPECT_EQ(3, static_cast<int>(predictor_->url_table_cache_.size()));
+
+  URLRequestSummary main_frame = CreateURLRequestSummary(
+      1, 1, "http://www.nike.com", "http://www.nike.com",
+      ResourceType::MAIN_FRAME, "", false);
+  predictor_->RecordURLRequest(main_frame);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  URLRequestSummary resource1 = CreateURLRequestSummary(
+      1, 1, "http://www.nike.com",  "http://nike.com/style1.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->RecordUrlResponse(resource1);
+  URLRequestSummary resource2 = CreateURLRequestSummary(
+      1, 1, "http://www.nike.com",  "http://nike.com/image2.png",
+      ResourceType::IMAGE, "image/png", false);
+  predictor_->RecordUrlResponse(resource2);
+
+  std::vector<GURL> urls_to_delete;
+  urls_to_delete.push_back(GURL("http://www.reddit.com"));
+  EXPECT_CALL(*mock_tables_, DeleteRowsForUrls(ContainerEq(urls_to_delete)));
+
+  UrlTableRows db_rows;
+  db_rows.push_back(UrlTableRow(
+      "http://www.nike.com", "http://nike.com/style1.css",
+      ResourceType::STYLESHEET, 1, 0, 0, 1.0));
+  db_rows.push_back(UrlTableRow(
+      "http://www.nike.com", "http://nike.com/image2.png",
+      ResourceType::IMAGE, 1, 0, 0, 2.0));
+  EXPECT_CALL(*mock_tables_,
+              UpdateRowsForUrl(GURL("http://www.nike.com"),
+                               ContainerEq(db_rows)));
+
+  predictor_->OnNavigationComplete(main_frame.navigation_id);
+}
+
+TEST_F(ResourcePrefetchPredictorTest, DeleteUrls) {
+  // Add some dummy entries to cache.
+  predictor_->url_table_cache_[GURL("http://www.google.com")];
+  predictor_->url_table_cache_[GURL("http://www.yahoo.com")];
+  predictor_->url_table_cache_[GURL("http://www.apple.com")];
+  predictor_->url_table_cache_[GURL("http://www.nike.com")];
+  predictor_->url_table_cache_[GURL("http://www.reddit.com")];
+
+  history::URLRows rows;
+  rows.push_back(history::URLRow(GURL("http://www.apple.com")));
+  rows.push_back(history::URLRow(GURL("http://www.yahoo.com")));
+
+  std::vector<GURL> urls_to_delete;
+  urls_to_delete.push_back(GURL("http://www.apple.com"));
+  urls_to_delete.push_back(GURL("http://www.yahoo.com"));
+  EXPECT_CALL(*mock_tables_, DeleteRowsForUrls(ContainerEq(urls_to_delete)));
+  predictor_->DeleteUrls(rows);
+  EXPECT_EQ(3, static_cast<int>(predictor_->url_table_cache_.size()));
+
+  EXPECT_CALL(*mock_tables_, DeleteAllRows());
+
+  predictor_->DeleteAllUrls();
+  EXPECT_TRUE(predictor_->url_table_cache_.empty());
+}
+
+TEST_F(ResourcePrefetchPredictorTest, OnMainFrameRequest) {
+  URLRequestSummary summary1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  URLRequestSummary summary2 = CreateURLRequestSummary(
+      1, 2, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  URLRequestSummary summary3 = CreateURLRequestSummary(
+      2, 1, "http://www.yahoo.com", "http://www.yahoo.com",
+      ResourceType::MAIN_FRAME, "", false);
+
+  predictor_->OnMainFrameRequest(summary1);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+  predictor_->OnMainFrameRequest(summary2);
+  EXPECT_EQ(2, static_cast<int>(predictor_->inflight_navigations_.size()));
+  predictor_->OnMainFrameRequest(summary3);
+  EXPECT_EQ(3, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  // Insert anther with same navigation id. It should replace.
+  URLRequestSummary summary4 = CreateURLRequestSummary(
+      1, 1, "http://www.nike.com", "http://www.nike.com",
+      ResourceType::MAIN_FRAME, "", false);
+  URLRequestSummary summary5 = CreateURLRequestSummary(
+      1, 2, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+
+  predictor_->OnMainFrameRequest(summary4);
+  EXPECT_EQ(3, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  // Change this creation time so that it will go away on the next insert.
+  summary5.navigation_id.creation_time = base::TimeTicks::Now() -
+      base::TimeDelta::FromDays(1);
+  predictor_->OnMainFrameRequest(summary5);
+  EXPECT_EQ(3, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  URLRequestSummary summary6 = CreateURLRequestSummary(
+      3, 1, "http://www.shoes.com", "http://www.shoes.com",
+      ResourceType::MAIN_FRAME, "", false);
+  predictor_->OnMainFrameRequest(summary6);
+  EXPECT_EQ(3, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  EXPECT_TRUE(predictor_->inflight_navigations_.find(summary3.navigation_id) !=
+              predictor_->inflight_navigations_.end());
+  EXPECT_TRUE(predictor_->inflight_navigations_.find(summary4.navigation_id) !=
+              predictor_->inflight_navigations_.end());
+  EXPECT_TRUE(predictor_->inflight_navigations_.find(summary6.navigation_id) !=
+              predictor_->inflight_navigations_.end());
+}
+
+TEST_F(ResourcePrefetchPredictorTest, OnMainFrameRedirect) {
+  URLRequestSummary summary1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  URLRequestSummary summary2 = CreateURLRequestSummary(
+      1, 2, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  URLRequestSummary summary3 = CreateURLRequestSummary(
+      2, 1, "http://www.yahoo.com", "http://www.yahoo.com",
+      ResourceType::MAIN_FRAME, "", false);
+
+  predictor_->OnMainFrameRedirect(summary1);
+  EXPECT_TRUE(predictor_->inflight_navigations_.empty());
+
+  predictor_->OnMainFrameRequest(summary1);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+  predictor_->OnMainFrameRequest(summary2);
+  EXPECT_EQ(2, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  predictor_->OnMainFrameRedirect(summary3);
+  EXPECT_EQ(2, static_cast<int>(predictor_->inflight_navigations_.size()));
+  predictor_->OnMainFrameRedirect(summary1);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+  predictor_->OnMainFrameRedirect(summary2);
+  EXPECT_TRUE(predictor_->inflight_navigations_.empty());
+}
+
+TEST_F(ResourcePrefetchPredictorTest, OnSubresourceResponse) {
+  // If there is no inflight navigation, nothing happens.
+  URLRequestSummary resource1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/style1.css",
+      ResourceType::STYLESHEET, "text/css", false);
+  predictor_->OnSubresourceResponse(resource1);
+  EXPECT_TRUE(predictor_->inflight_navigations_.empty());
+
+  // Add an inflight navigation.
+  URLRequestSummary main_frame1 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com", "http://www.google.com",
+      ResourceType::MAIN_FRAME, "", false);
+  predictor_->OnMainFrameRequest(main_frame1);
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+
+  // Now add a few subresources.
+  URLRequestSummary resource2 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script1.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  URLRequestSummary resource3 = CreateURLRequestSummary(
+      1, 1, "http://www.google.com",  "http://google.com/script2.js",
+      ResourceType::SCRIPT, "text/javascript", false);
+  predictor_->OnSubresourceResponse(resource1);
+  predictor_->OnSubresourceResponse(resource2);
+  predictor_->OnSubresourceResponse(resource3);
+
+  EXPECT_EQ(1, static_cast<int>(predictor_->inflight_navigations_.size()));
+  EXPECT_EQ(3, static_cast<int>(
+      predictor_->inflight_navigations_[main_frame1.navigation_id].size()));
+  EXPECT_TRUE(URLRequestSummaryAreEqual(
+      resource1,
+      predictor_->inflight_navigations_[main_frame1.navigation_id][0]));
+  EXPECT_TRUE(URLRequestSummaryAreEqual(
+      resource2,
+      predictor_->inflight_navigations_[main_frame1.navigation_id][1]));
+  EXPECT_TRUE(URLRequestSummaryAreEqual(
+      resource3,
+      predictor_->inflight_navigations_[main_frame1.navigation_id][2]));
+}
+
+}  // namespace predictors