Prerender: add true simultaneous nostate prefetch test.

chrome/browser/prerender/prerender_nostate_prefetch_browsertest.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/command_line.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_split.h"
 #include "base/task_scheduler/post_task.h"
 #include "chrome/browser/prerender/prerender_handle.h"
 #include "chrome/browser/prerender/prerender_manager.h"
@@ skipping 182 matching lines @@
   CountRequestForUrl(second_script_url, kPrefetchScript2, &second_script);
   PrefetchFromFile(kPrefetchMetaCSP, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
   // TODO(mattcary): See test comment above. If the meta CSP tag were parsed,
   // |second_script| would be loaded. Instead as the background scanner bails as
   // soon as the meta CSP tag is seen, only |main_page| is fetched.
   main_page.WaitForCount(1);
   second_script.WaitForCount(0);
   first_script.WaitForCount(0);
 }
 
-// Checks that the second prefetch request succeeds. TODO(pasko): This test
-// waits for Prerender Stop before starting the second request, add a test that
-// starts the second request from the UI thread immediately without waiting.
-IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchSimultaneous) {
+// Checks that the second prefetch request succeeds. This test waits for
+// Prerender Stop before starting the second request.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchMultipleRequest) {
   RequestCounter first_main_counter;
   CountRequestFor(kPrefetchPage, &first_main_counter);
   RequestCounter second_main_counter;
   CountRequestFor(kPrefetchPage2, &second_main_counter);
   RequestCounter first_script_counter;
   CountRequestFor(kPrefetchScript, &first_script_counter);
   RequestCounter second_script_counter;
   CountRequestFor(kPrefetchScript2, &second_script_counter);
 
-  // The first prerender is marked as canceled. When the second prerender
-  // starts, it sees that the first has been abandoned (because the earlier
-  // prerender is detached immediately and so dies quickly).
   PrefetchFromFile(kPrefetchPage, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
   PrefetchFromFile(kPrefetchPage2, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
   first_main_counter.WaitForCount(1);
   second_main_counter.WaitForCount(1);
   first_script_counter.WaitForCount(1);
   second_script_counter.WaitForCount(1);
 }
 
+// Checks that a second prefetch request, started before the first stops,
+// succeeds.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchSimultaneous) {
+  RequestCounter second_main_counter;
+  CountRequestFor(kPrefetchPage2, &second_main_counter);
+  RequestCounter second_script_counter;
+  CountRequestFor(kPrefetchScript2, &second_script_counter);
+
+  GURL first_url = src_server()->GetURL(MakeAbsolute(kPrefetchPage));
+  base::FilePath first_path = ui_test_utils::GetTestFilePath(
+      base::FilePath(), base::FilePath().AppendASCII(kPrefetchPage));
+
+  content::BrowserThread::PostTask(
+      content::BrowserThread::IO, FROM_HERE,
+      base::Bind(&test_utils::CreateHangingFirstRequestInterceptorOnIO,
+                 first_url, first_path, base::Closure()));
+
+  // Start the first prefetch directly instead of via PrefetchFromFile for the
+  // first prefetch to avoid the wait on prerender stop.
+  GURL first_loader_url = ServeLoaderURL(
+      kPrefetchLoaderPath, "REPLACE_WITH_PREFETCH_URL", first_url, "");
+  std::vector<FinalStatus> first_expected_status_queue(1,
+                                                       FINAL_STATUS_CANCELLED);
+  NavigateWithPrerenders(first_loader_url, first_expected_status_queue);
+
+  PrefetchFromFile(kPrefetchPage2, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
+  second_main_counter.WaitForCount(1);
+  second_script_counter.WaitForCount(1);
+}
+
 // Checks a prefetch to a nonexisting page.
 IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchNonexisting) {
   std::unique_ptr<TestPrerender> test_prerender = PrefetchFromFile(
       "nonexisting-page.html", FINAL_STATUS_UNSUPPORTED_SCHEME);
 }
 
 // Checks that a 301 redirect is followed.
 IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, Prefetch301Redirect) {
   RequestCounter script_counter;
   CountRequestFor(kPrefetchScript, &script_counter);
@@ skipping 148 matching lines @@
   // special way.
   // TODO(mattcary): since the prerender will count itself as loaded even if the
   // fetch of the main resource fails, the test doesn't actually confirm what we
   // want it to confirm. This may be fixed by planned changes to the prerender
   // lifecycle.
   std::unique_ptr<TestPrerender> prerender =
       PrefetchFromFile(kPrefetchPage, FINAL_STATUS_SAFE_BROWSING);
 }
 
 }  // namespace prerender