NoState Prefetch: nostate prefetch browser tests.

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/string_split.h"
+#include "chrome/browser/prerender/prerender_manager.h"
+#include "chrome/browser/prerender/prerender_manager_factory.h"
+#include "chrome/browser/prerender/prerender_test_utils.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/task_manager/task_manager_browsertest_util.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/browser_commands.h"
+#include "chrome/browser/ui/tabs/tab_strip_model.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/grit/generated_resources.h"
+#include "chrome/test/base/ui_test_utils.h"
+#include "content/public/common/content_switches.h"
+#include "content/public/common/url_constants.h"
+#include "content/public/test/browser_test_utils.h"
+#include "net/base/escape.h"
+#include "net/dns/mock_host_resolver.h"
+#include "net/test/embedded_test_server/request_handler_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/base/l10n/l10n_util.h"
+
+using prerender::test_utils::CreateCountingInterceptorOnIO;
+using prerender::test_utils::DestructionWaiter;
+using prerender::test_utils::RequestCounter;
+using prerender::test_utils::TestPrerender;
+using prerender::test_utils::TestPrerenderContents;
+using task_manager::browsertest_util::WaitForTaskManagerRows;
+
+namespace {
+// Fetches a boolean value from javascript. Returns whether the fetch
+// succeeded; the value of the variable is returned in value. If
+// javascript_variable does not exist, this returns false and value is
+// unchanged. The function checks that script execution works.
+bool GetJavascriptBoolean(const std::string& javascript_variable,
+                          content::WebContents* web_contents,
+                          bool* value) {
+  // In order to detect unknown variables a three-valued return is needed.
+  int result;
+  EXPECT_TRUE(content::ExecuteScriptAndExtractInt(
+      web_contents,
+      "try { if (" + javascript_variable + ") { " +
+          "window.domAutomationController.send(1) } else { " +
+          "window.domAutomationController.send(0); } } catch(err) {" +
+          "window.domAutomationController.send(2) }",
+      &result));
+  if (result == 2) {
+    // This means an exception was caught, usually because of a missing
+    // variable.
+    return false;
+  }
+  *value = (result == 1);
+  return true;
+}
+
+// As above, but just checks for a missing variable.
+bool JavascriptVariableMissing(const std::string& javascript_variable,
+                               content::WebContents* web_contents) {
+  bool unused;
+  return !GetJavascriptBoolean(javascript_variable, web_contents, &unused);
+}
+
+}  // namespace
+
+namespace prerender {
+
+// These URLs used for test resources must be relative with the exception of
+// |PrefetchLoaderPath|, which is only used in |PrerenderTestURLImpl()|.
+const char kPrefetchImagePage[] = "prerender/prefetch_image.html";
+const char kPrefetchLoopPage[] = "prerender/prefetch_loop.html";
+const char kPrefetchJpeg[] = "prerender/image.jpeg";
+const char kPrefetchLoaderPath[] = "/prerender/prefetch_loader.html";
+const char kPrefetchPage[] = "prerender/prefetch_page.html";
+const char kPrefetchPage2[] = "prerender/prefetch_page2.html";
+const char kPrefetchPng[] = "prerender/image.png";
+const char kPrefetchScript[] = "prerender/prefetch.js";
+const char kPrefetchScript2[] = "prerender/prefetch2.js";
+const char kPrefetchSubresourceRedirectPage[] =
+    "prerender/prefetch_subresource_redirect.html";
+
+const char kPageBool[] = "pageBool";
+const char kScriptBool[] = "scriptBool";
+
+class NoStatePrefetchBrowserTest
+    : public test_utils::PrerenderInProcessBrowserTest {
+ public:
+  class BrowserTestTime : public PrerenderManager::TimeOverride {
+   public:
+    BrowserTestTime() {}
+
+    base::Time GetCurrentTime() const override {
+      if (delta_.is_zero()) {
+        return base::Time::Now();
+      }
+      return time_ + delta_;
+    }
+
+    base::TimeTicks GetCurrentTimeTicks() const override {
+      if (delta_.is_zero()) {
+        return base::TimeTicks::Now();
+      }
+      return time_ticks_ + delta_;
+    }
+
+    void AdvanceTime(base::TimeDelta delta) {
+      if (delta_.is_zero()) {

[pasko, 2016/10/05 12:35:25]

could this avoid storing delta_? In the c-tor it could initialize to
base::Time::Now() and then just adds delta on AdvanceTime().

This code seems to cover the case of returning time naturally when AdvanceTime()
was not called. Is it required? In all prior tests initializing a time override
declared that time is managed in the test and it worked well.

[mattcary, 2016/10/10 11:54:43]

This seemed the easier way to manipulate both time_ticks_ and time_, especially
if more complex time management is added in the future (as TimeTicks and Time
are mutually opaque).

[pasko, 2016/10/10 12:40:20]

I don't think TimeTicks and Time will ever need to be updated in sync. If some
code assumes that Time goes at the same rate as TimeTicks, then it is probably
buggy, no? And if there is a need, a test could manage both Time and TimeTicks
on the test level, no need to have subtleties in utility classes.

[mattcary, 2016/10/10 13:56:07]

Also discussed offline w/rt SimpleTestClock changes.

+        time_ = base::Time::Now();
+        time_ticks_ = base::TimeTicks::Now();
+        delta_ = delta;
+      } else {
+        delta_ += delta;
+      }
+    }
+
+   private:
+    base::Time time_;
+    base::TimeTicks time_ticks_;
+    base::TimeDelta delta_;
+  };
+
+  NoStatePrefetchBrowserTest() {}
+
+  void SetUpCommandLine(base::CommandLine* command_line) override {
+    PrerenderInProcessBrowserTest::SetUpCommandLine(command_line);
+    command_line->AppendSwitchASCII(
+        switches::kPrerenderMode, switches::kPrerenderModeSwitchValuePrefetch);
+  }
+
+  void SetUpOnMainThread() override {

[pasko, 2016/10/05 12:35:24]

I think we would need to call the parent's SetUpOnMainThread() here.

Sounds like it would be simpler to do this work in the constructor and just not
override this. The text fixture is re-created for every test anyway.

[mattcary, 2016/10/10 11:54:43]

? PrerenderInProcessBrowserTest is the parent of this class?

GetPrerenderManager() is null in the constructor, it's not initialized until
after the browser is created.

[pasko, 2016/10/10 12:40:20]

Yes.
Yes.

[mattcary, 2016/10/10 13:56:07]

Acknowledged.

[pasko, 2016/10/11 13:56:23]

Pardon, I don't know how, but I missed the fact that this method is called here.
The remainder of the comment related to desireability of manage the time
override here vs. the actual tests.

[mattcary, 2016/10/11 15:08:58]

Right, it can't be done in the constructor as the PrerenderManager doesn't exist
yet. We could just override it for the tests that adjust time, but that would
lead to a lot of repeated boilerplate and possible inconsistency on how time is
dealt with in tests.

+    PrerenderInProcessBrowserTest::SetUpOnMainThread();
+    std::unique_ptr<BrowserTestTime> test_time =
+        base::MakeUnique<BrowserTestTime>();
+    browser_test_time_ = test_time.get();
+    GetPrerenderManager()->SetTimeOverride(std::move(test_time));
+  }
+
+  // Set up a request counter for the path.
+  void CountRequestFor(const std::string& path, RequestCounter* counter) {
+    GURL::Replacements replacement;
+    replacement.SetPathStr(path);
+    const GURL url = src_server()->base_url().ReplaceComponents(replacement);
+    base::FilePath url_file =
+        ui_test_utils::GetTestFilePath(base::FilePath(), base::FilePath(path));
+    content::BrowserThread::PostTask(
+        content::BrowserThread::IO, FROM_HERE,
+        base::Bind(&CreateCountingInterceptorOnIO, url, url_file,
+                   counter->AsWeakPtr()));
+  }
+
+  BrowserTestTime* GetTimeOverride() const { return browser_test_time_; }

[pasko, 2016/10/05 12:35:25]

please make it private or explain why this method should be public

[mattcary, 2016/10/10 11:54:43]

It's used by the test subclasses, like all the other public methods (eg,
CountRequestFor). Those don't have comments. I suppose there's a bunch of
methods in general that could be made protected rather than public, but that
breaks with existing convention for tests. I'm trying to maintain consistency.

[pasko, 2016/10/10 12:40:20]

I see. I was thinking about my proposal where time overrides are created in each
test that needs them, in this case there would be no need in GetTimeOverride().

I would still ask for least possible visibility for all the new code. Makes
easier to reason about reachability of various members in various places, even
if the old code is less careful. Not sure this kind of consistency buys us
anything material.

[mattcary, 2016/10/10 13:56:07]

Looking through overrides of InProcessBrowserTest, methods that are used in
tests are consistently public (throughout the codebase as well as in the
prerender tests in particular). Why should we have a different convention here?
It just makes the review process longer to nit unnecessarily.

[pasko, 2016/10/11 13:56:23]

I am not sure we are talking about the same thing. I looked at a few
not-so-random in process browser test classes, found one that makes things
public and three that keep everything under protected:
CloudPolicyManagerTest, PhishingClassifierTest, ImageFetcherImplBrowserTest

what are you referring to as consistently public throughout the codebase?

[mattcary, 2016/10/11 15:08:58]

ErrorPageBrowserTest, UnloadTest, SdchBrowserTest... all the nontrivial
overrides when search for "InProcessBrowserTest"

[pasko, 2016/10/11 15:40:19]

SdchBrowserTest::SetUpCommandLine(...) is non-trivial and private.

Others: hm, indeed

So, given there are examples of both, there is really no consistency to
maintain. Knowing that the classes use the principle of least privilege makes it
easier to maintain. One possible disadvantage is that it is an extra mental load
to think what visibility each thing should be in, which does not seem applicable
here because some stuff is thrown to private nontrivially anyway.

Sounds like a nit though, feel free to leave it as is, taking too much time to
argue.

[mattcary, 2016/10/12 09:02:52]

Acknowledged.

+
+ private:
+  ScopedVector<TestPrerender> PrerenderTestURLImpl(
+      const GURL& prerender_url,
+      const std::vector<FinalStatus>& expected_final_status_queue,
+      int expected_number_of_loads) override {
+    base::StringPairs replacement_text;
+    replacement_text.push_back(
+        make_pair("REPLACE_WITH_PREFETCH_URL", prerender_url.spec()));
+    std::string replacement_path;
+    net::test_server::GetFilePathWithReplacements(
+        kPrefetchLoaderPath, replacement_text, &replacement_path);
+    GURL loader_url = src_server()->GetURL(replacement_path);
+
+    ScopedVector<TestPrerender> prerenders = NavigateWithPrerenders(
+        loader_url, expected_final_status_queue, expected_number_of_loads);
+
+    TestPrerenderContents* prerender_contents = prerenders[0]->contents();
+    CHECK(prerender_contents);
+    // Checks that the prerender contents final status is unchanged from its
+    // default value, meaning that the contents has not been destroyed.
+    EXPECT_EQ(FINAL_STATUS_MAX, prerender_contents->final_status());
+
+    EXPECT_EQ(expected_number_of_loads, prerenders[0]->number_of_loads());
+
+    return prerenders;
+  }
+
+  BrowserTestTime* browser_test_time_;
+};
+
+// Performs a full load of the target page and check that javascript values are
+// set as expected. This confirms that our test system is working correctly, so
+// that when the target page is prefetched it can be confirmed that javascript
+// is not executed.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, CheckJavascript) {
+  ui_test_utils::NavigateToURL(
+      current_browser(), src_server()->GetURL(MakeAbsolute(kPrefetchPage)));
+  content::WebContents* web_contents =
+      current_browser()->tab_strip_model()->GetActiveWebContents();
+
+  // Confirms that true and false values can appear.
+  bool value = false;
+  EXPECT_TRUE(GetJavascriptBoolean(kPageBool, web_contents, &value));
+  EXPECT_TRUE(value);
+  value = true;
+  EXPECT_TRUE(GetJavascriptBoolean("pageAntiBool", web_contents, &value));
+  EXPECT_FALSE(value);
+
+  // Confirm a value from the script is plumbed through.
+  value = false;
+  EXPECT_TRUE(GetJavascriptBoolean(kScriptBool, web_contents, &value));
+  EXPECT_TRUE(value);
+
+  // Confirm that the expected happens when a value doesn't exist.
+  EXPECT_TRUE(JavascriptVariableMissing("iDontExist", web_contents));
+}
+
+// Checks that a page is correctly prefetched in the case of a
+// <link rel=prerender> tag and then loaded into a tab in response to a
+// navigation, when NoState Prefetch is enabled, but that the page is not loaded
+// (which confirmed by checking that javascript is not executed).
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchSimple) {
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  RequestCounter main_counter;
+  CountRequestFor(kPrefetchPage, &main_counter);
+
+  std::unique_ptr<TestPrerender> test_prerender =
+      PrerenderTestURL(kPrefetchPage, FINAL_STATUS_APP_TERMINATING, 1);
+  main_counter.WaitForCount(1);
+  script_counter.WaitForCount(1);
+
+  content::WebContents* contents =
+      test_prerender->contents()->prerender_contents();
+  content::WebContents* active_contents =
+      current_browser()->tab_strip_model()->GetActiveWebContents();
+  EXPECT_TRUE(JavascriptVariableMissing(kPageBool, contents));
+  EXPECT_TRUE(JavascriptVariableMissing(kScriptBool, contents));
+  EXPECT_TRUE(JavascriptVariableMissing(kPageBool, active_contents));
+  EXPECT_TRUE(JavascriptVariableMissing(kScriptBool, active_contents));
+  histogram_tester().ExpectTotalCount("Prerender.PerceivedPLT", 1);
+  histogram_tester().ExpectBucketCount(
+      "Prerender.websame_NoStatePrefetchResponseTypes",
+      4 /* cacheable, main resource */, 1);
+  histogram_tester().ExpectBucketCount(
+      "Prerender.websame_NoStatePrefetchResponseTypes",
+      0 /* cacheable, non-main resource */, 1);
+  histogram_tester().ExpectTotalCount("Prerender.none_MainResourceRedirects",
+                                      0);
+  histogram_tester().ExpectTotalCount("Prerender.none_SubResourceRedirects", 0);
+}
+
+// Checks the TTFCP histograms on fast reuse of a prefetch.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchReusedWarm) {
+  PrerenderTestURL(kPrefetchPage, FINAL_STATUS_APP_TERMINATING, 1);
+  GetTimeOverride()->AdvanceTime(base::TimeDelta::FromSeconds(10));
+  ui_test_utils::NavigateToURL(
+      current_browser(), src_server()->GetURL(MakeAbsolute(kPrefetchPage)));
+  histogram_tester().ExpectTotalCount(
+      "Prerender.websame_NoStatePrefetchTTFCP.Warm.Cacheable", 1);
+  histogram_tester().ExpectTotalCount(
+      "Prerender.websame_NoStatePrefetchTTFCP.Cold.Cacheable", 0);
+}
+
+// Checks the histograms on slow reuse of a prefetch.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchReusedCold) {
+  PrerenderTestURL(kPrefetchPage, FINAL_STATUS_TIMED_OUT, 1);
+  GetTimeOverride()->AdvanceTime(base::TimeDelta::FromSeconds(600));
+  ui_test_utils::NavigateToURL(
+      current_browser(), src_server()->GetURL(MakeAbsolute(kPrefetchPage)));
+
+  histogram_tester().ExpectTotalCount(
+      "Prerender.websame_NoStatePrefetchTTFCP.Warm.Cacheable", 0);
+  histogram_tester().ExpectTotalCount(
+      "Prerender.websame_NoStatePrefetchTTFCP.Cold.Cacheable", 1);
+}
+
+// Checks the prefetch of an img tag.
+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.
+  PrerenderTestURL(main_page_path, FINAL_STATUS_APP_TERMINATING, 1);
+  image_counter.WaitForCount(1);
+}
+
+// Checks that a cross-domain prefetching works correctly by looking at
+// histograms.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchCrossDomain) {
+  static const std::string secondary_domain = "www.foo.com";
+  host_resolver()->AddRule(secondary_domain, "127.0.0.1");
+  GURL cross_domain_url(base::StringPrintf(
+      "http://%s:%d/%s", secondary_domain.c_str(),
+      embedded_test_server()->host_port_pair().port(), kPrefetchPage));
+  PrerenderTestURL(cross_domain_url, FINAL_STATUS_APP_TERMINATING, 1);
+  // TODO(mattcary): remove PLT histograms (here and elsewhere).
+  histogram_tester().ExpectTotalCount("Prerender.PerceivedPLT", 1);
+  histogram_tester().ExpectTotalCount("Prerender.none_PerceivedPLT", 1);
+  histogram_tester().ExpectTotalCount(
+      "Prerender.webcross_PrerenderNotSwappedInPLT", 1);
+}
+
+// Checks simultaneous prefetch.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchSimultaneous) {
+  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 as when the second starts, it
+  // sees that the first has been abandoned (presumably because it is detached
+  // immediately and so dies quickly).
+  PrerenderTestURL(kPrefetchPage, FINAL_STATUS_CANCELLED, 1);
+  PrerenderTestURL(kPrefetchPage2, FINAL_STATUS_APP_TERMINATING, 1);
+  first_main_counter.WaitForCount(1);
+  second_main_counter.WaitForCount(1);
+  first_script_counter.WaitForCount(1);
+  second_script_counter.WaitForCount(1);
+  histogram_tester().ExpectTotalCount("Prerender.PerceivedPLT", 2);
+  histogram_tester().ExpectTotalCount("Prerender.none_PerceivedPLT", 2);
+}
+
+// Checks a prefetch to a nonexisting page.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchNonexisting) {
+  PrerenderTestURL("nonexisting-page.html", FINAL_STATUS_APP_TERMINATING, 0);
+  // TODO(mattcary): we fire up a prerenderer before we discover that the main
+  // page doesn't exist, we still count this as a prerender. Also we don't fail
+  // the renderer (presumably because we've detached the resource, etc). Is this
+  // what we want?
+  histogram_tester().ExpectTotalCount("Prerender.PerceivedPLT", 1);
+}
+
+// Checks that a 301 redirect is followed.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, Prefetch301Redirect) {
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  PrerenderTestURL(
+      "/server-redirect/?" +
+          net::EscapeQueryParamValue(MakeAbsolute(kPrefetchPage), false),
+      FINAL_STATUS_APP_TERMINATING, 1);
+  script_counter.WaitForCount(1);
+  histogram_tester().ExpectTotalCount(
+      "Prerender.websame_NoStatePrefetchMainResourceRedirects", 1);
+}
+
+// Checks that a subresource 301 redirect is followed.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, Prefetch301Subresource) {
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  PrerenderTestURL(kPrefetchSubresourceRedirectPage,
+                   FINAL_STATUS_APP_TERMINATING, 1);
+  script_counter.WaitForCount(1);
+  histogram_tester().ExpectTotalCount(
+      "Prerender.websame_NoStatePrefetchMainResourceRedirects", 1);
+}
+
+// Checks a client redirect is not followed.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchClientRedirect) {
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  // A complete load of kPrefetchPage2 is used as a sentinal. Otherwise the test
+  // ends before script_counter would reliably see the load of kPrefetchScript,
+  // were it to happen.
+  RequestCounter sentinel_counter;
+  CountRequestFor(kPrefetchScript2, &sentinel_counter);
+  PrerenderTestURL(
+      "/client-redirect/?" +
+          net::EscapeQueryParamValue(MakeAbsolute(kPrefetchPage), false),
+      FINAL_STATUS_APP_TERMINATING, 1);
+  ui_test_utils::NavigateToURL(
+      current_browser(), src_server()->GetURL(MakeAbsolute(kPrefetchPage2)));
+  sentinel_counter.WaitForCount(1);
+  script_counter.WaitForCount(0);
+}
+
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchHttps) {
+  UseHttpsSrcServer();
+  RequestCounter main_counter;
+  CountRequestFor(kPrefetchPage, &main_counter);
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  PrerenderTestURL(kPrefetchPage, FINAL_STATUS_APP_TERMINATING, 1);
+  main_counter.WaitForCount(1);
+  script_counter.WaitForCount(1);
+}
+
+// Checks that an SSL error prevents prefetch.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, SSLError) {
+  // Only send the loaded page, not the loader, through SSL.
+  net::EmbeddedTestServer https_server(net::EmbeddedTestServer::TYPE_HTTPS);
+  https_server.SetSSLConfig(net::EmbeddedTestServer::CERT_MISMATCHED_NAME);
+  https_server.ServeFilesFromSourceDirectory("chrome/test/data");
+  ASSERT_TRUE(https_server.Start());
+  std::unique_ptr<TestPrerender> prerender =
+      PrerenderTestURL(https_server.GetURL(MakeAbsolute(kPrefetchPage)),
+                       FINAL_STATUS_SSL_ERROR, 0);
+  DestructionWaiter waiter(prerender->contents(), FINAL_STATUS_SSL_ERROR);
+  EXPECT_TRUE(waiter.WaitForDestroy());
+}
+
+// Checks that a subresource failing SSL does not prevent prefetch on the rest
+// of the page.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, SSLSubresourceError) {
+  // First confirm that the image loads as expected.
+
+  // A separate HTTPS server is started for the subresource; src_server() is
+  // non-HTTPS.
+  net::EmbeddedTestServer https_server(net::EmbeddedTestServer::TYPE_HTTPS);
+  https_server.SetSSLConfig(net::EmbeddedTestServer::CERT_MISMATCHED_NAME);
+  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);
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+
+  std::unique_ptr<TestPrerender> prerender =
+      PrerenderTestURL(main_page_path, FINAL_STATUS_APP_TERMINATING, 1);
+  // 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.
+  script_counter.WaitForCount(1);
+}
+
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, Loop) {
+  RequestCounter script_counter;
+  CountRequestFor(kPrefetchScript, &script_counter);
+  RequestCounter main_counter;
+  CountRequestFor(kPrefetchLoopPage, &main_counter);
+
+  std::unique_ptr<TestPrerender> test_prerender =
+      PrerenderTestURL(kPrefetchLoopPage, FINAL_STATUS_APP_TERMINATING, 1);
+  main_counter.WaitForCount(1);
+  script_counter.WaitForCount(1);
+}
+
+#if defined(ENABLE_TASK_MANAGER)
+
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest,
+                       OpenTaskManagerBeforePrefetch) {
+  const base::string16 any_prerender = MatchTaskManagerPrerender("*");
+  const base::string16 any_tab = MatchTaskManagerTab("*");
+  const base::string16 original = MatchTaskManagerTab("Prefetch Loader");
+  // The page title is not visible in the task manager, presumably because the
+  // page has not been fully parsed.
+  const base::string16 prerender =
+      MatchTaskManagerPrerender("*prefetch_page.html*");
+
+  // Show the task manager. This populates the model.
+  chrome::OpenTaskManager(current_browser());
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, any_tab));
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(0, any_prerender));
+
+  // Prerender a page in addition to the original tab.
+  PrerenderTestURL(kPrefetchPage, FINAL_STATUS_APP_TERMINATING, 1);
+
+  // A TaskManager entry should appear like "Prerender: Prerender Page"
+  // alongside the original tab entry. There should be just these two entries.
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, prerender));
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, original));
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, any_prerender));
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, any_tab));
+}
+
+#endif  // defined(ENABLE_TASK_MANAGER)
+
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, RendererCrash) {
+  std::unique_ptr<TestPrerender> prerender =
+      PrerenderTestURL(kPrefetchPage, FINAL_STATUS_RENDERER_CRASHED, 1);
+  prerender->contents()->prerender_contents()->GetController().LoadURL(
+      GURL(content::kChromeUICrashURL), content::Referrer(),
+      ui::PAGE_TRANSITION_TYPED, std::string());
+  prerender->WaitForStop();
+}
+
+// Checks that the prefetch of png correctly loads the png.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, Png) {
+  RequestCounter counter;
+  CountRequestFor(kPrefetchPng, &counter);
+  PrerenderTestURL(kPrefetchPng, FINAL_STATUS_APP_TERMINATING, 1);
+  counter.WaitForCount(1);
+}
+
+// Checks that the prefetch of png correctly loads the jpeg.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, Jpeg) {
+  RequestCounter counter;
+  CountRequestFor(kPrefetchJpeg, &counter);
+  PrerenderTestURL(kPrefetchJpeg, FINAL_STATUS_APP_TERMINATING, 1);
+  counter.WaitForCount(1);
+}
+
+// Checks that nothing is prefetched from malware sites.
+IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest,
+                       PrerenderSafeBrowsingTopLevel) {
+  GURL url = src_server()->GetURL(MakeAbsolute(kPrefetchPage));
+  GetFakeSafeBrowsingDatabaseManager()->SetThreatTypeForUrl(
+      url, safe_browsing::SB_THREAT_TYPE_URL_MALWARE);
+  // Prefetch resources are blocked, but the prerender is not killed in any
+  // 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 =
+      PrerenderTestURL(kPrefetchPage, FINAL_STATUS_APP_TERMINATING, 1);
+}
+
+}  // namespace prerender