Differential updates for components.

chrome/browser/component_updater/test/component_updater_service_unittest.cc

Index: chrome/browser/component_updater/test/component_updater_service_unittest.cc
diff --git a/chrome/browser/component_updater/test/component_updater_service_unittest.cc b/chrome/browser/component_updater/test/component_updater_service_unittest.cc
index 080b1d28c43ff8b1028384ef90934da81e286968..ccc6d1f7a5183bcf9253186fac2b386ca8f406b5 100644
--- a/chrome/browser/component_updater/test/component_updater_service_unittest.cc
+++ b/chrome/browser/component_updater/test/component_updater_service_unittest.cc
@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/component_updater/component_updater_service.h"
-
 #include <list>
 #include <utility>
 
@@ -13,7 +11,11 @@
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop.h"
 #include "base/path_service.h"
+#include "base/stringprintf.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/values.h"
+#include "chrome/browser/component_updater/component_updater_service.h"
+#include "chrome/browser/component_updater/test/component_patcher_mock.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_paths.h"
 #include "content/public/browser/notification_observer.h"
@@ -23,7 +25,11 @@
 #include "content/test/net/url_request_prepackaged_interceptor.h"
 #include "googleurl/src/gurl.h"
 #include "libxml/globals.h"
+#include "net/base/upload_bytes_element_reader.h"
 #include "net/url_request/url_fetcher.h"
+#include "net/url_request/url_request.h"
+#include "net/url_request/url_request_filter.h"
+#include "net/url_request/url_request_simple_job.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -31,98 +37,72 @@ using content::BrowserThread;
 using content::TestNotificationTracker;
 
 namespace {
-// Overrides some of the component updater behaviors so it is easier to test
-// and loops faster. In actual usage it takes hours do to a full cycle.
+
+// component 1 has extension id "jebgalgnebhfojomionfpkfelancnnkf", and
+// the RSA public key the following hash:
+const uint8 jebg_hash[] = {0x94, 0x16, 0x0b, 0x6d, 0x41, 0x75, 0xe9, 0xec,
+                           0x8e, 0xd5, 0xfa, 0x54, 0xb0, 0xd2, 0xdd, 0xa5,
+                           0x6e, 0x05, 0x6b, 0xe8, 0x73, 0x47, 0xf6, 0xc4,
+                           0x11, 0x9f, 0xbc, 0xb3, 0x09, 0xb3, 0x5b, 0x40};
+// component 2 has extension id "abagagagagagagagagagagagagagagag", and
+// the RSA public key the following hash:
+const uint8 abag_hash[] = {0x01, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+                           0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+                           0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+                           0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x01};
+// component 3 has extension id "ihfokbkgjpifnbbojhneepfflplebdkc", and
+// the RSA public key the following hash:
+const uint8 ihfo_hash[] = {0x87, 0x5e, 0xa1, 0xa6, 0x9f, 0x85, 0xd1, 0x1e,
+                           0x97, 0xd4, 0x4f, 0x55, 0xbf, 0xb4, 0x13, 0xa2,
+                           0xe7, 0xc5, 0xc8, 0xf5, 0x60, 0x19, 0x78, 0x1b,
+                           0x6d, 0xe9, 0x4c, 0xeb, 0x96, 0x05, 0x42, 0x17};
+
 class TestConfigurator : public ComponentUpdateService::Configurator {
  public:
-  TestConfigurator()
-      : times_(1), recheck_time_(0), ondemand_time_(0), cus_(NULL) {
-  }
+  TestConfigurator();
 
-  virtual int InitialDelay() OVERRIDE { return 0; }
+  virtual int InitialDelay() OVERRIDE;
 
   typedef std::pair<CrxComponent*, int> CheckAtLoopCount;
 
-  virtual int NextCheckDelay() OVERRIDE {
-    // This is called when a new full cycle of checking for updates is going
-    // to happen. In test we normally only test one cycle so it is a good
-    // time to break from the test messageloop Run() method so the test can
-    // finish.
-    if (--times_ <= 0) {
-      base::MessageLoop::current()->Quit();
-      return 0;
+  virtual int NextCheckDelay() OVERRIDE;
 
-    }
-
-    // Look for checks to issue in the middle of the loop.
-    for (std::list<CheckAtLoopCount>::iterator
-             i = components_to_check_.begin();
-         i != components_to_check_.end(); ) {
-      if (i->second == times_) {
-        cus_->CheckForUpdateSoon(*i->first);
-        i = components_to_check_.erase(i);
-      } else {
-        ++i;
-      }
-    }
-    return 1;
-  }
+  virtual int StepDelay() OVERRIDE;
 
-  virtual int StepDelay() OVERRIDE {
-    return 0;
-  }
+  virtual int MinimumReCheckWait() OVERRIDE;
 
-  virtual int MinimumReCheckWait() OVERRIDE {
-    return recheck_time_;
-  }
+  virtual int OnDemandDelay() OVERRIDE;
 
-  virtual int OnDemandDelay() OVERRIDE {
-    return ondemand_time_;
-  }
+  virtual GURL UpdateUrl(CrxComponent::UrlSource source) OVERRIDE;
 
-  virtual GURL UpdateUrl(CrxComponent::UrlSource source) OVERRIDE {
-    switch (source) {
-      case CrxComponent::BANDAID:
-        return GURL("http://localhost/upd");
-      case CrxComponent::CWS_PUBLIC:
-        return GURL("http://localhost/cws");
-      default:
-        return GURL("http://wronghost/bad");
-    };
-  }
+  virtual GURL PingUrl() OVERRIDE;
 
-  virtual const char* ExtraRequestParams() OVERRIDE { return "extra=foo"; }
+  virtual const char* ExtraRequestParams() OVERRIDE;
 
-  virtual size_t UrlSizeLimit() OVERRIDE { return 256; }
+  virtual size_t UrlSizeLimit() OVERRIDE;
 
-  virtual net::URLRequestContextGetter* RequestContext() OVERRIDE {
-    return new net::TestURLRequestContextGetter(
-        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
-  }
+  virtual net::URLRequestContextGetter* RequestContext() OVERRIDE;
 
   // Don't use the utility process to decode files.
-  virtual bool InProcess() OVERRIDE { return true; }
+  virtual bool InProcess() OVERRIDE;
 
-  virtual void OnEvent(Events event, int extra) OVERRIDE { }
+  virtual void OnEvent(Events event, int extra) OVERRIDE;
 
-  // Set how many update checks are called, the default value is just once.
-  void SetLoopCount(int times) { times_ = times; }
+  virtual ComponentPatcher* CreateComponentPatcher() OVERRIDE;
 
-  void SetRecheckTime(int seconds) {
-    recheck_time_ = seconds;
-  }
+  virtual bool PingsEnabled() const OVERRIDE;
 
-  void SetOnDemandTime(int seconds) {
-    ondemand_time_ = seconds;
-  }
+  virtual bool DeltasEnabled() const OVERRIDE;
 
-  void AddComponentToCheck(CrxComponent* com, int at_loop_iter) {
-    components_to_check_.push_back(std::make_pair(com, at_loop_iter));
-  }
+  void SetLoopCount(int times);
 
-  void SetComponentUpdateService(ComponentUpdateService* cus) {
-    cus_ = cus;
-  }
+  void SetRecheckTime(int seconds);
+
+  void SetOnDemandTime(int seconds);
+
+  void AddComponentToCheck(CrxComponent* com, int at_loop_iter);
+
+  void SetComponentUpdateService(ComponentUpdateService* cus);
 
  private:
   int times_;
@@ -135,131 +115,481 @@ class TestConfigurator : public ComponentUpdateService::Configurator {
 
 class TestInstaller : public ComponentInstaller {
  public :
-  explicit TestInstaller()
-      : error_(0), install_count_(0) {
-  }
+  explicit TestInstaller();
 
-  virtual void OnUpdateError(int error) OVERRIDE {
-    EXPECT_NE(0, error);
-    error_ = error;
-  }
+  virtual void OnUpdateError(int error) OVERRIDE;
 
   virtual bool Install(const base::DictionaryValue& manifest,
-                       const base::FilePath& unpack_path) OVERRIDE {
-    ++install_count_;
-    return file_util::Delete(unpack_path, true);
-  }
+                       const base::FilePath& unpack_path) OVERRIDE;
 
-  int error() const { return error_; }
+  virtual bool GetInstalledFile(const std::string& file,
+                                base::FilePath* installed_file) OVERRIDE;
 
-  int install_count() const { return install_count_; }
+  int error() const;
 
- private:
+  int install_count() const;
+
+ protected:
   int error_;
   int install_count_;
 };
 
-// component 1 has extension id "jebgalgnebhfojomionfpkfelancnnkf", and
-// the RSA public key the following hash:
-const uint8 jebg_hash[] = {0x94,0x16,0x0b,0x6d,0x41,0x75,0xe9,0xec,0x8e,0xd5,
-                           0xfa,0x54,0xb0,0xd2,0xdd,0xa5,0x6e,0x05,0x6b,0xe8,
-                           0x73,0x47,0xf6,0xc4,0x11,0x9f,0xbc,0xb3,0x09,0xb3,
-                           0x5b,0x40};
-// component 2 has extension id "abagagagagagagagagagagagagagagag", and
-// the RSA public key the following hash:
-const uint8 abag_hash[] = {0x01,0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,
-                           0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,
-                           0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,0x06,
-                           0x06,0x01};
+class PersistentTestInstaller : public TestInstaller {
+ public :
+  explicit PersistentTestInstaller();
 
-const char expected_crx_url[] =
-    "http://localhost/download/jebgalgnebhfojomionfpkfelancnnkf.crx";
+  virtual ~PersistentTestInstaller();
 
-}  // namespace
+  virtual bool Install(const base::DictionaryValue& manifest,
+                       const base::FilePath& unpack_path) OVERRIDE;
+
+  virtual bool GetInstalledFile(const std::string& file,
+                                base::FilePath* installed_file) OVERRIDE;
+
+ private:
+  base::FilePath install_directory_;
+  Version current_version_;
+};
 
-// Common fixture for all the component updater tests.
 class ComponentUpdaterTest : public testing::Test {
  public:
   enum TestComponents {
     kTestComponent_abag,
-    kTestComponent_jebg
+    kTestComponent_jebg,
+    kTestComponent_ihfo,
   };
 
-  ComponentUpdaterTest() : test_config_(NULL) {
-    // The component updater instance under test.
-    test_config_ = new TestConfigurator;
-    component_updater_.reset(ComponentUpdateServiceFactory(test_config_));
-    test_config_->SetComponentUpdateService(component_updater_.get());
-    // The test directory is chrome/test/data/components.
-    PathService::Get(chrome::DIR_TEST_DATA, &test_data_dir_);
-    test_data_dir_ = test_data_dir_.AppendASCII("components");
-
-    // Subscribe to all component updater notifications.
-    const int notifications[] = {
-      chrome::NOTIFICATION_COMPONENT_UPDATER_STARTED,
-      chrome::NOTIFICATION_COMPONENT_UPDATER_SLEEPING,
-      chrome::NOTIFICATION_COMPONENT_UPDATE_FOUND,
-      chrome::NOTIFICATION_COMPONENT_UPDATE_READY
-    };
-
-    for (int ix = 0; ix != arraysize(notifications); ++ix) {
-      notification_tracker_.ListenFor(
-          notifications[ix], content::NotificationService::AllSources());
-    }
-    net::URLFetcher::SetEnableInterceptionForTests(true);
-  }
+  ComponentUpdaterTest();
 
-  virtual ~ComponentUpdaterTest() {
-    net::URLFetcher::SetEnableInterceptionForTests(false);
-  }
+  virtual ~ComponentUpdaterTest();
 
-  virtual void TearDown() {
-    xmlCleanupGlobals();
-  }
+  virtual void TearDown();
 
-  ComponentUpdateService* component_updater() {
-    return component_updater_.get();
-  }
+  ComponentUpdateService* component_updater();
 
   // Makes the full path to a component updater test file.
-  const base::FilePath test_file(const char* file) {
-    return test_data_dir_.AppendASCII(file);
-  }
+  const base::FilePath test_file(const char* file);
 
-  TestNotificationTracker& notification_tracker() {
-    return notification_tracker_;
-  }
+  TestNotificationTracker& notification_tracker();
 
-  TestConfigurator* test_configurator() {
-    return test_config_;
-  }
+  TestConfigurator* test_configurator();
 
   ComponentUpdateService::Status RegisterComponent(CrxComponent* com,
                                                    TestComponents component,
-                                                   const Version& version) {
-    if (component == kTestComponent_abag) {
-      com->name = "test_abag";
-      com->pk_hash.assign(abag_hash, abag_hash + arraysize(abag_hash));
-    } else {
-      com->name = "test_jebg";
-      com->pk_hash.assign(jebg_hash, jebg_hash + arraysize(jebg_hash));
-    }
-    com->version = version;
-    TestInstaller* installer = new TestInstaller;
-    com->installer = installer;
-    test_installers_.push_back(installer);
-    return component_updater_->RegisterComponent(*com);
-  }
+                                                   const Version& version,
+                                                   TestInstaller* installer);
 
  private:
   scoped_ptr<ComponentUpdateService> component_updater_;
   base::FilePath test_data_dir_;
   TestNotificationTracker notification_tracker_;
   TestConfigurator* test_config_;
-  // ComponentInstaller objects to delete after each test.
-  ScopedVector<TestInstaller> test_installers_;
 };
 
+const char expected_crx_url[] =
+    "http://localhost/download/jebgalgnebhfojomionfpkfelancnnkf.crx";
+
+class PingChecker {

[erikwright (departed), 2013/06/17 17:24:28]

These classes are sufficiently complicated that I would suggest moving them to
their own file(s).

In fact, I would argue that they need unittests of their own since it will be
very hard for someone else to maintain them, otherwise.

[waffles, 2013/06/17 23:51:07]

I've moved the POST interceptors into a separate file, but kept the PingChecker
here, since it feels very closely tied with this code.

I haven't added unit tests for them.

+ public:
+  explicit PingChecker(const std::map<std::string, std::string>& attributes);
+
+  virtual ~PingChecker();
+
+  void Trial(net::URLRequest* request);
+
+  int NumHits() const {
+    return num_hits_;
+  }
+  int NumMisses() const {
+    return num_misses_;
+  }
+
+ private:
+  int num_hits_;
+  int num_misses_;
+  const std::map<std::string, std::string> attributes_;
+  virtual bool Test(net::URLRequest* request);
+};
+
+PingChecker::PingChecker(const std::map<std::string, std::string>& attributes)
+    : num_hits_(0), num_misses_(0), attributes_(attributes) {
+}
+
+PingChecker::~PingChecker() {}
+
+void PingChecker::Trial(net::URLRequest* request) {
+  if (Test(request))
+    ++num_hits_;
+  else
+    ++num_misses_;
+}
+
+bool PingChecker::Test(net::URLRequest* request) {
+  if (request->has_upload()) {
+    const net::UploadDataStream* stream = request->get_upload();
+    const net::UploadBytesElementReader* reader =
+        stream->element_readers()[0]->AsBytesReader();
+    int size = reader->length();
+    scoped_refptr <net::IOBuffer> buffer = new net::IOBuffer(size);
+    std::string data(reader->bytes());
+    // For now, we assume that there is only one ping per POST.
+    std::string::size_type start = data.find("<o:event");
+    if (start != std::string::npos) {
+      std::string::size_type end = data.find(">", start);
+      if (end != std::string::npos) {
+        std::string ping = data.substr(start, end - start);
+        std::map<std::string, std::string>::const_iterator iter;
+        for (iter = attributes_.begin(); iter != attributes_.end(); ++iter) {
+          // does the ping contain the specified attribute/value?
+          if (ping.find(std::string(" ") + (iter->first) +
+              std::string("=") + (iter->second)) == string::npos) {
+            return false;
+          }
+        }
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+class URLRequestPostInterceptor {
+ public:
+  explicit URLRequestPostInterceptor(PingChecker* counter);
+  virtual ~URLRequestPostInterceptor();
+
+ private:
+  class Delegate;
+
+  // After creation, |delegate_| lives on the IO thread, and a task to delete it
+  // is posted from ~URLRequestPostInterceptor().
+  Delegate* delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(URLRequestPostInterceptor);
+};
+
+class URLRequestPostInterceptor::Delegate
+    : public net::URLRequestJobFactory::ProtocolHandler {
+ public:
+  explicit Delegate(PingChecker* counter);
+  virtual ~Delegate() {}
+
+  void Register();
+
+  void Unregister();
+
+ private:
+  PingChecker* counter_;
+
+  virtual net::URLRequestJob* MaybeCreateJob(
+      net::URLRequest* request,
+      net::NetworkDelegate* network_delegate) const OVERRIDE;
+};
+
+class URLRequestPingMockJob : public net::URLRequestSimpleJob {
+ public:
+  URLRequestPingMockJob(net::URLRequest* request,
+                        net::NetworkDelegate* network_delegate);
+
+ protected:
+  virtual int GetData(std::string* mime_type,
+                      std::string* charset,
+                      std::string* data,
+                      const net::CompletionCallback& callback) const OVERRIDE;
+
+ private:
+  virtual ~URLRequestPingMockJob() {}
+
+  DISALLOW_COPY_AND_ASSIGN(URLRequestPingMockJob);
+};
+
+URLRequestPostInterceptor::URLRequestPostInterceptor(
+    PingChecker* counter) : delegate_(new Delegate(counter)) {
+  BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                          base::Bind(&Delegate::Register,
+                                     base::Unretained(delegate_)));
+}
+
+URLRequestPostInterceptor::~URLRequestPostInterceptor() {
+  BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                          base::Bind(&Delegate::Unregister,
+                                     base::Unretained(delegate_)));
+}
+
+URLRequestPostInterceptor::Delegate::Delegate(
+    PingChecker* counter) : counter_(counter) {
+}
+
+void URLRequestPostInterceptor::Delegate::Register() {
+  net::URLRequestFilter::GetInstance()->AddHostnameProtocolHandler(
+      "http", "localhost2",
+      scoped_ptr<net::URLRequestJobFactory::ProtocolHandler>(this));
+}
+
+void URLRequestPostInterceptor::Delegate::Unregister() {
+  net::URLRequestFilter::GetInstance()->
+      RemoveHostnameHandler("http", "localhost2");
+}
+
+net::URLRequestJob* URLRequestPostInterceptor::Delegate::MaybeCreateJob(
+    net::URLRequest* request,
+    net::NetworkDelegate* network_delegate) const {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  if (request->has_upload()) {
+    counter_->Trial(request);
+    return new URLRequestPingMockJob(request, network_delegate);
+  }
+  return NULL;
+}
+
+URLRequestPingMockJob::URLRequestPingMockJob(
+    net::URLRequest* request,
+    net::NetworkDelegate* network_delegate)
+    : net::URLRequestSimpleJob(request, network_delegate) {
+}
+
+int URLRequestPingMockJob::GetData(
+    std::string* mime_type,
+    std::string* charset,
+    std::string* data,
+    const net::CompletionCallback& callback) const {
+  mime_type->assign("text/plain");
+  charset->assign("US-ASCII");
+  data->assign("");  // There is no reason to have a response body in this test.
+  return net::OK;
+}
+
+}  // namespace
+
+TestInstaller::TestInstaller()
+    : error_(0), install_count_(0) {
+}
+
+void TestInstaller::OnUpdateError(int error) {
+  EXPECT_NE(0, error);
+  error_ = error;
+}
+
+bool TestInstaller::Install(const base::DictionaryValue& manifest,
+                            const base::FilePath& unpack_path) {
+  ++install_count_;
+  return file_util::Delete(unpack_path, true);
+}
+
+bool TestInstaller::GetInstalledFile(const std::string& file,
+                                     base::FilePath* installed_file) {
+  return false;
+}
+
+int TestInstaller::error() const { return error_; }
+
+int TestInstaller::install_count() const { return install_count_; }
+
+PersistentTestInstaller::PersistentTestInstaller() {
+  file_util::CreateNewTempDirectory(FILE_PATH_LITERAL("TEST_"),
+                                    &install_directory_);
+}
+
+PersistentTestInstaller::~PersistentTestInstaller() {
+  file_util::Delete(install_directory_, true);
+}
+
+bool PersistentTestInstaller::Install(const base::DictionaryValue& manifest,
+                                      const base::FilePath& unpack_path) {
+  std::string version_string;
+  manifest.GetStringASCII("version", &version_string);
+  Version version(version_string.c_str());
+
+  base::FilePath path;
+  path = install_directory_.AppendASCII(version.GetString());
+  file_util::CreateDirectory(path.DirName());
+  if (!file_util::Move(unpack_path, path))
+    return false;
+  current_version_ = version;
+  ++install_count_;
+  return true;
+}
+
+bool PersistentTestInstaller::GetInstalledFile(const std::string& file,
+                                               base::FilePath* installed_file) {
+  base::FilePath path;
+  path = install_directory_.AppendASCII(current_version_.GetString());
+  *installed_file = path.Append(base::FilePath::FromUTF8Unsafe(file));
+  return true;
+}
+
+TestConfigurator::TestConfigurator()
+    : times_(1), recheck_time_(0), ondemand_time_(0), cus_(NULL) {
+}
+
+int TestConfigurator::InitialDelay() { return 0; }
+
+int TestConfigurator::NextCheckDelay() {
+  // This is called when a new full cycle of checking for updates is going
+  // to happen. In test we normally only test one cycle so it is a good
+  // time to break from the test messageloop Run() method so the test can
+  // finish.
+  if (--times_ <= 0) {
+    base::MessageLoop::current()->Quit();
+    return 0;
+  }
+
+  // Look for checks to issue in the middle of the loop.
+  for (std::list<CheckAtLoopCount>::iterator
+           i = components_to_check_.begin();
+       i != components_to_check_.end(); ) {
+    if (i->second == times_) {
+      cus_->CheckForUpdateSoon(*i->first);
+      i = components_to_check_.erase(i);
+    } else {
+      ++i;
+    }
+  }
+  return 1;
+}
+
+int TestConfigurator::StepDelay() {
+  return 0;
+}
+
+int TestConfigurator::MinimumReCheckWait() {
+  return recheck_time_;
+}
+
+int TestConfigurator::OnDemandDelay() {
+  return ondemand_time_;
+}
+
+GURL TestConfigurator::UpdateUrl(CrxComponent::UrlSource source) {
+  switch (source) {
+    case CrxComponent::BANDAID:
+      return GURL("http://localhost/upd");
+    case CrxComponent::CWS_PUBLIC:
+      return GURL("http://localhost/cws");
+    default:
+      return GURL("http://wronghost/bad");
+  };
+}
+
+GURL TestConfigurator::PingUrl() {
+  return GURL("http://localhost2/ping");
+}
+
+const char* TestConfigurator::ExtraRequestParams() { return "extra=foo"; }
+
+size_t TestConfigurator::UrlSizeLimit() { return 256; }
+
+net::URLRequestContextGetter* TestConfigurator::RequestContext() {
+  return new net::TestURLRequestContextGetter(
+      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
+}
+
+// Don't use the utility process to decode files.
+bool TestConfigurator::InProcess() { return true; }
+
+void TestConfigurator::OnEvent(Events event, int extra) { }
+
+ComponentPatcher* TestConfigurator::CreateComponentPatcher() {
+  return new MockComponentPatcher();
+}
+
+bool TestConfigurator::PingsEnabled() const {
+  return true;
+}
+
+bool TestConfigurator::DeltasEnabled() const {
+  return true;
+}
+
+// Set how many update checks are called, the default value is just once.
+void TestConfigurator::SetLoopCount(int times) { times_ = times; }
+
+void TestConfigurator::SetRecheckTime(int seconds) {
+  recheck_time_ = seconds;
+}
+
+void TestConfigurator::SetOnDemandTime(int seconds) {
+  ondemand_time_ = seconds;
+}
+
+void TestConfigurator::AddComponentToCheck(CrxComponent* com,
+                                           int at_loop_iter) {
+  components_to_check_.push_back(std::make_pair(com, at_loop_iter));
+}
+
+void TestConfigurator::SetComponentUpdateService(ComponentUpdateService* cus) {
+  cus_ = cus;
+}
+
+ComponentUpdaterTest::ComponentUpdaterTest() : test_config_(NULL) {
+  // The component updater instance under test.
+  test_config_ = new TestConfigurator;
+  component_updater_.reset(ComponentUpdateServiceFactory(test_config_));
+  test_config_->SetComponentUpdateService(component_updater_.get());
+  // The test directory is chrome/test/data/components.
+  PathService::Get(chrome::DIR_TEST_DATA, &test_data_dir_);
+  test_data_dir_ = test_data_dir_.AppendASCII("components");
+
+  // Subscribe to all component updater notifications.
+  const int notifications[] = {
+    chrome::NOTIFICATION_COMPONENT_UPDATER_STARTED,
+    chrome::NOTIFICATION_COMPONENT_UPDATER_SLEEPING,
+    chrome::NOTIFICATION_COMPONENT_UPDATE_FOUND,
+    chrome::NOTIFICATION_COMPONENT_UPDATE_READY
+  };
+
+  for (int ix = 0; ix != arraysize(notifications); ++ix) {
+    notification_tracker_.ListenFor(
+        notifications[ix], content::NotificationService::AllSources());
+  }
+  net::URLFetcher::SetEnableInterceptionForTests(true);
+}
+
+ComponentUpdaterTest::~ComponentUpdaterTest() {
+  net::URLFetcher::SetEnableInterceptionForTests(false);
+}
+
+void ComponentUpdaterTest::TearDown() {
+  xmlCleanupGlobals();
+}
+
+ComponentUpdateService* ComponentUpdaterTest::component_updater() {
+  return component_updater_.get();
+}
+
+  // Makes the full path to a component updater test file.
+const base::FilePath ComponentUpdaterTest::test_file(const char* file) {
+  return test_data_dir_.AppendASCII(file);
+}
+
+TestNotificationTracker& ComponentUpdaterTest::notification_tracker() {
+  return notification_tracker_;
+}
+
+TestConfigurator* ComponentUpdaterTest::test_configurator() {
+  return test_config_;
+}
+
+ComponentUpdateService::Status ComponentUpdaterTest::RegisterComponent(
+    CrxComponent* com,
+    TestComponents component,
+    const Version& version,
+    TestInstaller* installer) {
+  if (component == kTestComponent_abag) {
+    com->name = "test_abag";
+    com->pk_hash.assign(abag_hash, abag_hash + arraysize(abag_hash));
+  } else if (component == kTestComponent_jebg) {
+    com->name = "test_jebg";
+    com->pk_hash.assign(jebg_hash, jebg_hash + arraysize(jebg_hash));
+  } else {
+    com->name = "test_ihfo";
+    com->pk_hash.assign(ihfo_hash, ihfo_hash + arraysize(ihfo_hash));
+  }
+  com->version = version;
+  com->installer = installer;
+  return component_updater_->RegisterComponent(*com);
+}
+
 // Verify that our test fixture work and the component updater can
 // be created and destroyed with no side effects.
 TEST_F(ComponentUpdaterTest, VerifyFixture) {
@@ -295,13 +625,17 @@ TEST_F(ComponentUpdaterTest, CheckCrxSleep) {
 
   content::URLLocalHostRequestPrepackagedInterceptor interceptor;
 
+  TestInstaller installer;
   CrxComponent com;
   EXPECT_EQ(ComponentUpdateService::kOk,
-            RegisterComponent(&com, kTestComponent_abag, Version("1.1")));
+            RegisterComponent(&com,
+                              kTestComponent_abag,
+                              Version("1.1"),
+                              &installer));
 
   const GURL expected_update_url(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D1.1%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D1.1%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url,
                           test_file("updatecheck_reply_1.xml"));
@@ -359,7 +693,7 @@ TEST_F(ComponentUpdaterTest, CheckCrxSleep) {
 // the notifications above NOTIFICATION_COMPONENT_UPDATE_FOUND and
 // NOTIFICATION_COMPONENT_UPDATE_READY should have been fired. We do two loops
 // so the second time around there should be nothing left to do.
-// We also check that only 3 network requests are issued:
+// We also check that only 3 non-ping network requests are issued:
 // 1- manifest check
 // 2- download crx
 // 3- second manifest check.
@@ -372,22 +706,32 @@ TEST_F(ComponentUpdaterTest, InstallCrx) {
   io_thread.StartIOThread();
   file_thread.Start();
 
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("previousversion",
+                                                 "\"0.9\""));
+  map.insert(std::pair<std::string, std::string>("nextversion", "\"1.0\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
   content::URLLocalHostRequestPrepackagedInterceptor interceptor;
 
+  TestInstaller installer1;
   CrxComponent com1;
-  RegisterComponent(&com1, kTestComponent_jebg, Version("0.9"));
+  RegisterComponent(&com1, kTestComponent_jebg, Version("0.9"), &installer1);
+  TestInstaller installer2;
   CrxComponent com2;
-  RegisterComponent(&com2, kTestComponent_abag, Version("2.2"));
+  RegisterComponent(&com2, kTestComponent_abag, Version("2.2"), &installer2);
 
   const GURL expected_update_url_1(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26uc&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc");
 
   const GURL expected_update_url_2(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D1.0%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D1.0%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url_1,
                           test_file("updatecheck_reply_1.xml"));
@@ -407,6 +751,8 @@ TEST_F(ComponentUpdaterTest, InstallCrx) {
   EXPECT_EQ(0, static_cast<TestInstaller*>(com2.installer)->install_count());
 
   EXPECT_EQ(3, interceptor.GetHitCount());
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
 
   ASSERT_EQ(5ul, notification_tracker().size());
 
@@ -437,21 +783,31 @@ TEST_F(ComponentUpdaterTest, InstallCrxTwoSources) {
   io_thread.StartIOThread();
   file_thread.Start();
 
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("previousversion",
+                                                 "\"0.9\""));
+  map.insert(std::pair<std::string, std::string>("nextversion", "\"1.0\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
   content::URLLocalHostRequestPrepackagedInterceptor interceptor;
 
+  TestInstaller installer1;
   CrxComponent com1;
-  RegisterComponent(&com1, kTestComponent_abag, Version("2.2"));
+  RegisterComponent(&com1, kTestComponent_abag, Version("2.2"), &installer1);
+  TestInstaller installer2;
   CrxComponent com2;
   com2.source = CrxComponent::CWS_PUBLIC;
-  RegisterComponent(&com2, kTestComponent_jebg, Version("0.9"));
+  RegisterComponent(&com2, kTestComponent_jebg, Version("0.9"), &installer2);
 
   const GURL expected_update_url_1(
       "http://localhost/upd?extra=foo&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc");
+      "abagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc");
 
   const GURL expected_update_url_2(
       "http://localhost/cws?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26uc");
+      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url_1,
                           test_file("updatecheck_reply_3.xml"));
@@ -475,6 +831,8 @@ TEST_F(ComponentUpdaterTest, InstallCrxTwoSources) {
   EXPECT_EQ(0, static_cast<TestInstaller*>(com2.installer)->error());
   EXPECT_EQ(1, static_cast<TestInstaller*>(com2.installer)->install_count());
 
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
   EXPECT_EQ(3, interceptor.GetHitCount());
 
   ASSERT_EQ(6ul, notification_tracker().size());
@@ -509,14 +867,18 @@ TEST_F(ComponentUpdaterTest, ProdVersionCheck) {
   io_thread.StartIOThread();
   file_thread.Start();
 
+  std::map<std::string, std::string> map;
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
   content::URLLocalHostRequestPrepackagedInterceptor interceptor;
 
+  TestInstaller installer;
   CrxComponent com;
-  RegisterComponent(&com, kTestComponent_jebg, Version("0.9"));
+  RegisterComponent(&com, kTestComponent_jebg, Version("0.9"), &installer);
 
   const GURL expected_update_url(
       "http://localhost/upd?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26uc");
+      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url,
                           test_file("updatecheck_reply_2.xml"));
@@ -527,6 +889,8 @@ TEST_F(ComponentUpdaterTest, ProdVersionCheck) {
   component_updater()->Start();
   message_loop.Run();
 
+  EXPECT_EQ(0, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
   EXPECT_EQ(1, interceptor.GetHitCount());
   EXPECT_EQ(0, static_cast<TestInstaller*>(com.installer)->error());
   EXPECT_EQ(0, static_cast<TestInstaller*>(com.installer)->install_count());
@@ -549,22 +913,32 @@ TEST_F(ComponentUpdaterTest, CheckForUpdateSoon) {
   io_thread.StartIOThread();
   file_thread.Start();
 
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("previousversion",
+                                                 "\"0.9\""));
+  map.insert(std::pair<std::string, std::string>("nextversion", "\"1.0\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
   content::URLLocalHostRequestPrepackagedInterceptor interceptor;
 
+  TestInstaller installer1;
   CrxComponent com1;
-  RegisterComponent(&com1, kTestComponent_abag, Version("2.2"));
+  RegisterComponent(&com1, kTestComponent_abag, Version("2.2"), &installer1);
+  TestInstaller installer2;
   CrxComponent com2;
-  RegisterComponent(&com2, kTestComponent_jebg, Version("0.9"));
+  RegisterComponent(&com2, kTestComponent_jebg, Version("0.9"), &installer2);
 
   const GURL expected_update_url_1(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc");
 
   const GURL expected_update_url_2(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26uc&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url_1,
                           test_file("updatecheck_reply_empty"));
@@ -613,9 +987,9 @@ TEST_F(ComponentUpdaterTest, CheckForUpdateSoon) {
   // Test a few error cases. NOTE: We don't have callbacks for
   // when the updates failed yet.
   const GURL expected_update_url_3(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D1.0%26uc&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D1.0%26fp%3D%26uc"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc");
 
   // No update: error from no server response
   interceptor.SetResponse(expected_update_url_3,
@@ -646,6 +1020,8 @@ TEST_F(ComponentUpdaterTest, CheckForUpdateSoon) {
 
   message_loop.Run();
 
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
   ASSERT_EQ(2ul, notification_tracker().size());
   ev0 = notification_tracker().at(0);
   EXPECT_EQ(chrome::NOTIFICATION_COMPONENT_UPDATER_STARTED, ev0.type);
@@ -665,23 +1041,33 @@ TEST_F(ComponentUpdaterTest, CheckReRegistration) {
   io_thread.StartIOThread();
   file_thread.Start();
 
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("previousversion",
+                                                 "\"0.9\""));
+  map.insert(std::pair<std::string, std::string>("nextversion", "\"1.0\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
   content::URLLocalHostRequestPrepackagedInterceptor interceptor;
 
+  TestInstaller installer1;
   CrxComponent com1;
-  RegisterComponent(&com1, kTestComponent_jebg, Version("0.9"));
+  RegisterComponent(&com1, kTestComponent_jebg, Version("0.9"), &installer1);
+  TestInstaller installer2;
   CrxComponent com2;
-  RegisterComponent(&com2, kTestComponent_abag, Version("2.2"));
+  RegisterComponent(&com2, kTestComponent_abag, Version("2.2"), &installer2);
 
   // Start with 0.9, and update to 1.0
   const GURL expected_update_url_1(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26uc&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc");
 
   const GURL expected_update_url_2(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D1.0%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D1.0%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url_1,
                           test_file("updatecheck_reply_1.xml"));
@@ -702,6 +1088,8 @@ TEST_F(ComponentUpdaterTest, CheckReRegistration) {
   EXPECT_EQ(0, static_cast<TestInstaller*>(com2.installer)->error());
   EXPECT_EQ(0, static_cast<TestInstaller*>(com2.installer)->install_count());
 
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
   EXPECT_EQ(3, interceptor.GetHitCount());
 
   ASSERT_EQ(5ul, notification_tracker().size());
@@ -722,16 +1110,20 @@ TEST_F(ComponentUpdaterTest, CheckReRegistration) {
   EXPECT_EQ(chrome::NOTIFICATION_COMPONENT_UPDATER_SLEEPING, ev4.type);
 
   // Now re-register, pretending to be an even newer version (2.2)
+  TestInstaller installer3;
   component_updater()->Stop();
   EXPECT_EQ(ComponentUpdateService::kReplaced,
-            RegisterComponent(&com1, kTestComponent_jebg, Version("2.2")));
+            RegisterComponent(&com1,
+                              kTestComponent_jebg,
+                              Version("2.2"),
+                              &installer3));
 
   // Check that we send out 2.2 as our version.
   // Interceptor's hit count should go up by 1.
   const GURL expected_update_url_3(
-      "http://localhost/upd?extra=foo&x=id%3D"
-      "jebgalgnebhfojomionfpkfelancnnkf%26v%3D2.2%26uc&x=id%3D"
-      "abagagagagagagagagagagagagagagag%26v%3D2.2%26uc");
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D2.2%26fp%3D%26uc"
+      "&x=id%3Dabagagagagagagagagagagagagagagag%26v%3D2.2%26fp%3D%26uc");
 
   interceptor.SetResponse(expected_update_url_3,
                           test_file("updatecheck_reply_1.xml"));
@@ -753,8 +1145,7 @@ TEST_F(ComponentUpdaterTest, CheckReRegistration) {
 
   EXPECT_EQ(4, interceptor.GetHitCount());
 
-  // The test harness's Register() function creates a new installer,
-  // so the counts go back to 0.
+  // We created a new installer, so the counts go back to 0.
   EXPECT_EQ(0, static_cast<TestInstaller*>(com1.installer)->error());
   EXPECT_EQ(0, static_cast<TestInstaller*>(com1.installer)->install_count());
   EXPECT_EQ(0, static_cast<TestInstaller*>(com2.installer)->error());
@@ -762,3 +1153,289 @@ TEST_F(ComponentUpdaterTest, CheckReRegistration) {
 
   component_updater()->Stop();
 }
+
+// Verify that we can download and install a component and a differential
+// update to that component. We do three loops; the final loop should do
+// nothing.
+// We also check that exactly 5 non-ping network requests are issued:
+// 1- update check (response: v1 available)
+// 2- download crx (v1)
+// 3- update check (response: v2 available)
+// 4- download differential crx (v1 to v2)
+// 5- update check (response: no further update available)
+// There should be two pings, one for each update. The second will bear a
+// diffresult=1, while the first will not.
+TEST_F(ComponentUpdaterTest, DifferentialUpdate) {
+  base::MessageLoop message_loop;
+  content::TestBrowserThread ui_thread(BrowserThread::UI, &message_loop);
+  content::TestBrowserThread file_thread(BrowserThread::FILE);
+  content::TestBrowserThread io_thread(BrowserThread::IO);
+
+  io_thread.StartIOThread();
+  file_thread.Start();
+
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("diffresult", "\"1\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
+  content::URLLocalHostRequestPrepackagedInterceptor interceptor;
+
+  PersistentTestInstaller installer;
+  CrxComponent com;
+  RegisterComponent(&com, kTestComponent_ihfo, Version("0.0"), &installer);
+
+  const GURL expected_update_url_0(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D0.0%26fp%3D%26uc");
+  const GURL expected_update_url_1(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D1.0%26fp%3D1%26uc");
+  const GURL expected_update_url_2(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D2.0%26fp%3Df22%26uc");
+  const GURL expected_crx_url_1(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_1.crx");
+  const GURL expected_crx_url_1_diff_2(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_1to2.crx");
+
+  interceptor.SetResponse(expected_update_url_0,
+                          test_file("updatecheck_diff_reply_1.xml"));
+  interceptor.SetResponse(expected_update_url_1,
+                          test_file("updatecheck_diff_reply_2.xml"));
+  interceptor.SetResponse(expected_update_url_2,
+                          test_file("updatecheck_diff_reply_3.xml"));
+  interceptor.SetResponse(expected_crx_url_1,
+                          test_file("ihfokbkgjpifnbbojhneepfflplebdkc_1.crx"));
+  interceptor.SetResponse(
+      expected_crx_url_1_diff_2,
+      test_file("ihfokbkgjpifnbbojhneepfflplebdkc_1to2.crx"));
+
+  test_configurator()->SetLoopCount(3);
+
+  component_updater()->Start();
+  message_loop.Run();
+
+  EXPECT_EQ(0, static_cast<TestInstaller*>(com.installer)->error());
+  EXPECT_EQ(2, static_cast<TestInstaller*>(com.installer)->install_count());
+
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(1, ping_checker.NumMisses());
+  EXPECT_EQ(5, interceptor.GetHitCount());
+
+  component_updater()->Stop();
+}
+
+// Verify that component installation falls back to downloading and installing
+// a full update if the differential update fails (in this case, because the
+// installer does not know about the existing files). We do two loops; the final
+// loop should do nothing.
+// We also check that exactly 4 non-ping network requests are issued:
+// 1- update check (loop 1)
+// 2- download differential crx
+// 3- download full crx
+// 4- update check (loop 2 - no update available)
+// There should be one ping for the first attempted update.
+TEST_F(ComponentUpdaterTest, DifferentialUpdateFails) {
+  base::MessageLoop message_loop;
+  content::TestBrowserThread ui_thread(BrowserThread::UI, &message_loop);
+  content::TestBrowserThread file_thread(BrowserThread::FILE);
+  content::TestBrowserThread io_thread(BrowserThread::IO);
+
+  io_thread.StartIOThread();
+  file_thread.Start();
+
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("diffresult", "\"0\""));
+  map.insert(std::pair<std::string, std::string>("differrorcode", "\"16\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
+  content::URLLocalHostRequestPrepackagedInterceptor interceptor;
+
+  TestInstaller installer;
+  CrxComponent com;
+  RegisterComponent(&com, kTestComponent_ihfo, Version("1.0"), &installer);
+
+  const GURL expected_update_url_1(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D1.0%26fp%3D%26uc");
+  const GURL expected_update_url_2(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D2.0%26fp%3Df22%26uc");
+  const GURL expected_crx_url_1(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_1.crx");
+  const GURL expected_crx_url_1_diff_2(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_1to2.crx");
+  const GURL expected_crx_url_2(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_2.crx");
+
+  interceptor.SetResponse(expected_update_url_1,
+                          test_file("updatecheck_diff_reply_2.xml"));
+  interceptor.SetResponse(expected_update_url_2,
+                          test_file("updatecheck_diff_reply_3.xml"));
+  interceptor.SetResponse(expected_crx_url_1,
+                          test_file("ihfokbkgjpifnbbojhneepfflplebdkc_1.crx"));
+  interceptor.SetResponse(
+      expected_crx_url_1_diff_2,
+      test_file("ihfokbkgjpifnbbojhneepfflplebdkc_1to2.crx"));
+  interceptor.SetResponse(expected_crx_url_2,
+                          test_file("ihfokbkgjpifnbbojhneepfflplebdkc_2.crx"));
+
+  test_configurator()->SetLoopCount(2);
+
+  component_updater()->Start();
+  message_loop.Run();
+
+  // A failed differential update does not count as a failed install.
+  EXPECT_EQ(0, static_cast<TestInstaller*>(com.installer)->error());
+  EXPECT_EQ(1, static_cast<TestInstaller*>(com.installer)->install_count());
+
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
+  EXPECT_EQ(4, interceptor.GetHitCount());
+
+  component_updater()->Stop();
+}
+
+// Verify that a failed installation causes an install failure ping.
+TEST_F(ComponentUpdaterTest, CheckFailedInstallPing) {
+  base::MessageLoop message_loop;
+  content::TestBrowserThread ui_thread(BrowserThread::UI, &message_loop);
+  content::TestBrowserThread file_thread(BrowserThread::FILE);
+  content::TestBrowserThread io_thread(BrowserThread::IO);
+
+  io_thread.StartIOThread();
+  file_thread.Start();
+
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"0\""));
+  map.insert(std::pair<std::string, std::string>("errorcode", "\"9\""));
+  map.insert(std::pair<std::string, std::string>("previousversion",
+                                                 "\"0.9\""));
+  map.insert(std::pair<std::string, std::string>("nextversion", "\"1.0\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
+  content::URLLocalHostRequestPrepackagedInterceptor interceptor;
+
+  // This test installer reports installation failure.
+  class : public TestInstaller {
+    virtual bool Install(const base::DictionaryValue& manifest,
+                         const base::FilePath& unpack_path) OVERRIDE {
+      ++install_count_;
+      file_util::Delete(unpack_path, true);
+      return false;
+    }
+  } installer;
+
+  CrxComponent com;
+  RegisterComponent(&com, kTestComponent_jebg, Version("0.9"), &installer);
+
+  // Start with 0.9, and attempt update to 1.0
+  const GURL expected_update_url_1(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Djebgalgnebhfojomionfpkfelancnnkf%26v%3D0.9%26fp%3D%26uc");
+
+  interceptor.SetResponse(expected_update_url_1,
+                          test_file("updatecheck_reply_1.xml"));
+  interceptor.SetResponse(GURL(expected_crx_url),
+                          test_file("jebgalgnebhfojomionfpkfelancnnkf.crx"));
+
+  // Loop twice to issue two checks: (1) with original 0.9 version
+  // and (2), which should retry with 0.9.
+  test_configurator()->SetLoopCount(2);
+  component_updater()->Start();
+  message_loop.Run();
+
+  // Loop once more, but expect no ping because a noupdate response is issued.
+  // This is necessary to clear out the fire-and-forget ping from the previous
+  // iteration.
+  interceptor.SetResponse(expected_update_url_1,
+                          test_file("updatecheck_reply_noupdate.xml"));
+  test_configurator()->SetLoopCount(1);
+  component_updater()->Start();
+  message_loop.Run();
+
+  EXPECT_EQ(0, static_cast<TestInstaller*>(com.installer)->error());
+  EXPECT_EQ(2, static_cast<TestInstaller*>(com.installer)->install_count());
+
+  EXPECT_EQ(2, ping_checker.NumHits());
+  EXPECT_EQ(0, ping_checker.NumMisses());
+  EXPECT_EQ(5, interceptor.GetHitCount());
+
+  component_updater()->Stop();
+}
+
+// Verify that we successfully propagate a patcher error.
+// ihfokbkgjpifnbbojhneepfflplebdkc_1to2_bad.crx contains an incorrect
+// patching instruction that should fail.
+TEST_F(ComponentUpdaterTest, DifferentialUpdateFailErrorcode) {
+  base::MessageLoop message_loop;
+  content::TestBrowserThread ui_thread(BrowserThread::UI, &message_loop);
+  content::TestBrowserThread file_thread(BrowserThread::FILE);
+  content::TestBrowserThread io_thread(BrowserThread::IO);
+
+  io_thread.StartIOThread();
+  file_thread.Start();
+
+  std::map<std::string, std::string> map;
+  map.insert(std::pair<std::string, std::string>("eventtype", "\"3\""));
+  map.insert(std::pair<std::string, std::string>("eventresult", "\"1\""));
+  map.insert(std::pair<std::string, std::string>("diffresult", "\"0\""));
+  map.insert(std::pair<std::string, std::string>("differrorcode", "\"14\""));
+  map.insert(std::pair<std::string, std::string>("diffextracode1", "\"305\""));
+  PingChecker ping_checker(map);
+  URLRequestPostInterceptor post_interceptor(&ping_checker);
+  content::URLLocalHostRequestPrepackagedInterceptor interceptor;
+
+  PersistentTestInstaller installer;
+  CrxComponent com;
+  RegisterComponent(&com, kTestComponent_ihfo, Version("0.0"), &installer);
+
+  const GURL expected_update_url_0(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D0.0%26fp%3D%26uc");
+  const GURL expected_update_url_1(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D1.0%26fp%3D1%26uc");
+  const GURL expected_update_url_2(
+      "http://localhost/upd?extra=foo"
+      "&x=id%3Dihfokbkgjpifnbbojhneepfflplebdkc%26v%3D2.0%26fp%3Df22%26uc");
+  const GURL expected_crx_url_1(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_1.crx");
+  const GURL expected_crx_url_1_diff_2(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_1to2.crx");
+  const GURL expected_crx_url_2(
+      "http://localhost/download/ihfokbkgjpifnbbojhneepfflplebdkc_2.crx");
+
+  interceptor.SetResponse(expected_update_url_0,
+                          test_file("updatecheck_diff_reply_1.xml"));
+  interceptor.SetResponse(expected_update_url_1,
+                          test_file("updatecheck_diff_reply_2.xml"));
+  interceptor.SetResponse(expected_update_url_2,
+                          test_file("updatecheck_diff_reply_3.xml"));
+  interceptor.SetResponse(expected_crx_url_1,
+                          test_file("ihfokbkgjpifnbbojhneepfflplebdkc_1.crx"));
+  interceptor.SetResponse(
+      expected_crx_url_1_diff_2,
+      test_file("ihfokbkgjpifnbbojhneepfflplebdkc_1to2_bad.crx"));
+  interceptor.SetResponse(expected_crx_url_2,
+                          test_file("ihfokbkgjpifnbbojhneepfflplebdkc_2.crx"));
+
+  test_configurator()->SetLoopCount(3);
+
+  component_updater()->Start();
+  message_loop.Run();
+
+  EXPECT_EQ(0, static_cast<TestInstaller*>(com.installer)->error());
+  EXPECT_EQ(2, static_cast<TestInstaller*>(com.installer)->install_count());
+
+  EXPECT_EQ(1, ping_checker.NumHits());
+  EXPECT_EQ(1, ping_checker.NumMisses());
+  EXPECT_EQ(6, interceptor.GetHitCount());
+
+  component_updater()->Stop();
+}