Prerender: Disable prefetch if there's an appcache (unflaked tests)

chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc

Index: chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc
diff --git a/chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc b/chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc
index 65551c02de58d59c99c39ad334468b006e804518..ecd184603c075034e793d07ca048085d831e1d85 100644
--- a/chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc
+++ b/chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc
@@ -3,10 +3,14 @@
 // found in the LICENSE file.
 
 #include "base/command_line.h"
+#include "base/memory/ptr_util.h"
+#include "base/memory/ref_counted.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_split.h"
+#include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/task_scheduler/post_task.h"
+#include "base/test/simple_test_tick_clock.h"
 #include "chrome/browser/history/history_service_factory.h"
 #include "chrome/browser/history/history_test_utils.h"
 #include "chrome/browser/prerender/prerender_handle.h"
@@ -21,7 +25,9 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/grit/generated_resources.h"
 #include "chrome/test/base/ui_test_utils.h"
+#include "content/public/browser/appcache_service.h"
 #include "content/public/browser/render_process_host.h"
+#include "content/public/browser/storage_partition.h"
 #include "content/public/common/result_codes.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/test/browser_test_utils.h"
@@ -40,6 +46,8 @@ namespace prerender {
 
 // These URLs used for test resources must be relative with the exception of
 // |kPrefetchLoaderPath|.
+const char kPrefetchAppcache[] = "prerender/prefetch_appcache.html";
+const char kPrefetchAppcacheManifest[] = "prerender/appcache.manifest";
 const char kPrefetchImagePage[] = "prerender/prefetch_image.html";
 const char kPrefetchJpeg[] = "prerender/image.jpeg";
 const char kPrefetchLoaderPath[] = "/prerender/prefetch_loader.html";
@@ -89,6 +97,32 @@ class NoStatePrefetchBrowserTest
                    url_file, counter->AsWeakPtr()));
   }
 
+  base::SimpleTestTickClock* OverridePrerenderManagerTimeTicks() {
+    auto clock = base::MakeUnique<base::SimpleTestTickClock>();
+    auto* clock_ptr = clock.get();
+    // The default zero time causes the prerender manager to do strange things.
+    clock->Advance(base::TimeDelta::FromSeconds(1));
+    GetPrerenderManager()->SetTickClockForTesting(std::move(clock));
+    return clock_ptr;
+  }
+
+  // Block until an AppCache exists for |manifest_url|.
+  void WaitForAppcache(const GURL& manifest_url) {
+    bool found_manifest = false;
+    content::AppCacheService* appcache_service =
+        content::BrowserContext::GetDefaultStoragePartition(
+            current_browser()->profile())
+            ->GetAppCacheService();
+    do {
+      base::RunLoop wait_loop;
+      content::BrowserThread::PostTask(
+          content::BrowserThread::IO, FROM_HERE,
+          base::Bind(WaitForAppcacheOnIO, manifest_url, appcache_service,
+                     wait_loop.QuitClosure(), &found_manifest));
+      wait_loop.Run();
+    } while (!found_manifest);

[droger, 2017/04/13 13:40:29]

Can we remove the while loop and just EXPECT_TRUE(found_manifest)?

[mattcary, 2017/04/13 14:05:53]

No, it sometimes takes a while for the manifest to get read & created. I suppose
it depends on the timing of the manifest resource fetch which is racing with our
GetAllAppCacheInfo call.

+  }
+
  protected:
   std::unique_ptr<TestPrerender> PrefetchFromURL(
       const GURL& target_url,
@@ -111,6 +145,45 @@ class NoStatePrefetchBrowserTest
   }
 
  private:
+  // Schedule a task to retrieve AppCacheInfo from |appcache_service|. This sets
+  // |found_manifest| if an appcache exists for |manifest_url|. |callback| will
+  // be called on the UI thread after the info is retrieved, whether or not the
+  // manifest exists.
+  static void WaitForAppcacheOnIO(const GURL& manifest_url,
+                                  content::AppCacheService* appcache_service,
+                                  base::Closure callback,
+                                  bool* found_manifest) {
+    scoped_refptr<content::AppCacheInfoCollection> info_collection =
+        new content::AppCacheInfoCollection();
+    appcache_service->GetAllAppCacheInfo(
+        info_collection.get(),
+        base::Bind(ProcessAppCacheInfo, manifest_url, callback, found_manifest,
+                   info_collection));
+  }
+
+  // Look through |info_collection| for an entry matching |target_manifest|,
+  // setting |found_manifest| appropriately. Then |callback| will be invoked on
+  // the UI thread.
+  static void ProcessAppCacheInfo(
+      const GURL& target_manifest,
+      base::Closure callback,
+      bool* found_manifest,
+      scoped_refptr<content::AppCacheInfoCollection> info_collection,
+      int status) {
+    if (status == net::OK) {
+      for (const auto& origin_pair : info_collection->infos_by_origin) {
+        for (const auto& info : origin_pair.second) {
+          if (info.manifest_url == target_manifest) {
+            *found_manifest = true;
+            break;
+          }
+        }
+      }
+    }
+    content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
+                                     callback);
+  }
+
   DISALLOW_COPY_AND_ASSIGN(NoStatePrefetchBrowserTest);
 };
 
@@ -185,15 +258,10 @@ IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchHistograms) {
 IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchImage) {
   RequestCounter image_counter;
   CountRequestFor(kPrefetchJpeg, &image_counter);
-  base::StringPairs replacement_text;
-  replacement_text.push_back(
-      std::make_pair("REPLACE_WITH_IMAGE_URL", MakeAbsolute(kPrefetchJpeg)));
-  std::string main_page_path;
-  net::test_server::GetFilePathWithReplacements(
-      kPrefetchImagePage, replacement_text, &main_page_path);
-  // Note CountRequestFor cannot be used on the main page as the test server
-  // must handling the image url replacement.
-  PrefetchFromFile(main_page_path, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
+  GURL main_page_url =
+      GetURLWithReplacement(kPrefetchImagePage, "REPLACE_WITH_IMAGE_URL",
+                            MakeAbsolute(kPrefetchJpeg));
+  PrefetchFromURL(main_page_url, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
   image_counter.WaitForCount(1);
 }
 
@@ -405,17 +473,13 @@ IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, SSLSubresourceError) {
   https_server.ServeFilesFromSourceDirectory("chrome/test/data");
   ASSERT_TRUE(https_server.Start());
   GURL https_url = https_server.GetURL("/prerender/image.jpeg");
-  base::StringPairs replacement_text;
-  replacement_text.push_back(
-      std::make_pair("REPLACE_WITH_IMAGE_URL", https_url.spec()));
-  std::string main_page_path;
-  net::test_server::GetFilePathWithReplacements(
-      kPrefetchImagePage, replacement_text, &main_page_path);
+  GURL main_page_url = GetURLWithReplacement(
+      kPrefetchImagePage, "REPLACE_WITH_IMAGE_URL", https_url.spec());
   RequestCounter script_counter;
   CountRequestFor(kPrefetchScript, &script_counter);
 
   std::unique_ptr<TestPrerender> prerender =
-      PrefetchFromFile(main_page_path, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
+      PrefetchFromURL(main_page_url, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
   // Checks that the presumed failure of the image load didn't affect the script
   // fetch. This assumes waiting for the script load is enough to see any error
   // from the image load.
@@ -603,4 +667,94 @@ IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, ServiceWorkerIntercept) {
   image_counter.WaitForCount(1);
 }
 
+// Checks that prefetching happens if an appcache is mentioned in the html tag
+// but is uninitialized.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, AppCacheHtmlUninitialized) {
+  RequestCounter image_counter;
+  CountRequestFor(kPrefetchPng, &image_counter);
+  PrefetchFromFile(kPrefetchAppcache, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
+  image_counter.WaitForCount(1);
+}
+
+// Checks that prefetching does not if an initialized appcache is mentioned in
+// the html tag.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, AppCacheHtmlInitialized) {
+  base::TimeTicks current_time = GetPrerenderManager()->GetCurrentTimeTicks();
+  auto* clock = OverridePrerenderManagerTimeTicks();
+  // Some navigations have already occurred in test setup. In order to track
+  // duplicate prefetches correctly the test clock needs to be beyond those
+  // navigations.
+  clock->SetNowTicks(current_time);
+  clock->Advance(base::TimeDelta::FromSeconds(600));
+
+  // Fill manifest with the image url. The main resource will be cached
+  // implicitly.
+  GURL image_url = src_server()->GetURL(MakeAbsolute(kPrefetchPng));
+  GURL manifest_url = GetURLWithReplacement(
+      kPrefetchAppcacheManifest, "REPLACE_WITH_URL", image_url.spec());
+  GURL appcache_page_url = GetURLWithReplacement(
+      kPrefetchAppcache, "REPLACE_WITH_MANIFEST", manifest_url.spec());
+
+  // Load the page into the appcache.
+  ui_test_utils::NavigateToURL(current_browser(), appcache_page_url);
+
+  WaitForAppcache(manifest_url);
+
+  // If a page is prefetch shortly after being loading, the prefetch is
+  // canceled. Advancing the clock prevents the cancelation.
+  clock->Advance(base::TimeDelta::FromSeconds(6000));
+
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  // While the prefetch stops when it sees the AppCache manifest, from the point
+  // of view of the prerender manager the prefetch stops normally.
+  PrefetchFromURL(appcache_page_url, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
+
+  // The prefetch should have been canceled before the script in
+  // kPrefetchAppcache is loaded (note the script is not mentioned in the
+  // manifest).
+  script_counter.WaitForCount(0);
+}
+
+// If a page has been cached by another AppCache, the prefetch should be
+// canceled.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, AppCacheRegistered) {
+  base::TimeTicks current_time = GetPrerenderManager()->GetCurrentTimeTicks();
+  auto* clock = OverridePrerenderManagerTimeTicks();
+  // Some navigations have already occurred in test setup. In order to track
+  // duplicate prefetches correctly the test clock needs to be beyond those
+  // navigations.
+  clock->SetNowTicks(current_time);
+  clock->Advance(base::TimeDelta::FromSeconds(600));
+
+  // Fill manifest with kPrefetchPage so that it is cached without explicitly
+  // listing a manifest.
+  GURL prefetch_page_url = src_server()->GetURL(MakeAbsolute(kPrefetchPage));
+  GURL manifest_url = GetURLWithReplacement(
+      kPrefetchAppcacheManifest, "REPLACE_WITH_URL", prefetch_page_url.spec());
+
+  GURL appcache_page_url = GetURLWithReplacement(
+      kPrefetchAppcache, "REPLACE_WITH_MANIFEST", manifest_url.spec());
+
+  // Load the page into the appcache.
+  ui_test_utils::NavigateToURL(current_browser(), appcache_page_url);
+  // Load the prefetch page so it can be cached.
+  ui_test_utils::NavigateToURL(current_browser(), prefetch_page_url);
+
+  WaitForAppcache(manifest_url);
+
+  // If a page is prefetch shortly after being loading, the prefetch is
+  // canceled. Advancing the clock prevents the cancelation.
+  clock->Advance(base::TimeDelta::FromSeconds(6000));
+
+  RequestCounter page_counter;
+  CountRequestFor(kPrefetchPage, &page_counter);
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  PrefetchFromURL(prefetch_page_url, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
+  // Neither the page nor the script should be prefetched.
+  script_counter.WaitForCount(0);
+  page_counter.WaitForCount(0);
+}
+
 }  // namespace prerender