Refactor code that defers extension background page loading

extensions/browser/process_manager_unittest.cc

 // Copyright 2014 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 "extensions/browser/process_manager.h"
 
 #include "chrome/browser/chrome_notification_types.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/site_instance.h"
 #include "content/public/test/test_browser_context.h"
 #include "extensions/browser/test_extensions_browser_client.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using content::BrowserContext;
 using content::SiteInstance;
 using content::TestBrowserContext;
 
 namespace extensions {
 
 namespace {
 
 // An incognito version of a TestBrowserContext.
 class TestBrowserContextIncognito : public TestBrowserContext {
  public:
   TestBrowserContextIncognito() {}
   virtual ~TestBrowserContextIncognito() {}
 
   // TestBrowserContext implementation.
   virtual bool IsOffTheRecord() const OVERRIDE { return true; }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TestBrowserContextIncognito);
 };
 
+// A trivial ProcessManagerDelegate.
+class TestProcessManagerDelegate : public ProcessManagerDelegate {
+ public:
+  TestProcessManagerDelegate()
+      : is_background_page_allowed_(true),
+        defer_creating_startup_background_hosts_(false) {}
+  virtual ~TestProcessManagerDelegate() {}
+
+  // ProcessManagerDelegate implementation.
+  virtual bool IsBackgroundPageAllowed(BrowserContext* context) const OVERRIDE {
+    return is_background_page_allowed_;
+  }
+  virtual bool DeferCreatingStartupBackgroundHosts(
+      BrowserContext* context) const OVERRIDE {
+    return defer_creating_startup_background_hosts_;
+  }
+
+  bool is_background_page_allowed_;
+  bool defer_creating_startup_background_hosts_;
+};
+
 }  // namespace
 
 class ProcessManagerTest : public testing::Test {
  public:
   ProcessManagerTest() : extensions_browser_client_(&original_context_) {
     extensions_browser_client_.SetIncognitoContext(&incognito_context_);
+    extensions_browser_client_.set_process_manager_delegate(
+        &process_manager_delegate_);
     ExtensionsBrowserClient::Set(&extensions_browser_client_);
   }
 
   virtual ~ProcessManagerTest() {
     ExtensionsBrowserClient::Set(NULL);
   }
 
   BrowserContext* original_context() { return &original_context_; }
   BrowserContext* incognito_context() { return &incognito_context_; }
 
+  // testing::Test implementation.
+  virtual void SetUp() OVERRIDE {
+    // Needed for ExtensionRegistry.
+    BrowserContextDependencyManager::GetInstance()
+        ->CreateBrowserContextServicesForTest(&original_context_);
+    BrowserContextDependencyManager::GetInstance()
+        ->CreateBrowserContextServicesForTest(&incognito_context_);
+  }
+
+  virtual void TearDown() OVERRIDE {
+    // Needed to clean up ExtensionRegistry.
+    BrowserContextDependencyManager::GetInstance()
+        ->DestroyBrowserContextServices(&incognito_context_);
+    BrowserContextDependencyManager::GetInstance()
+        ->DestroyBrowserContextServices(&original_context_);
+  }
+
   // Returns true if the notification |type| is registered for |manager| with
   // source |context|. Pass NULL for |context| for all sources.
   static bool IsRegistered(ProcessManager* manager,
                            int type,
                            BrowserContext* context) {
     return manager->registrar_.IsRegistered(
         manager, type, content::Source<BrowserContext>(context));
   }
 
- private:
+ protected:
   TestBrowserContext original_context_;
   TestBrowserContextIncognito incognito_context_;
+  TestProcessManagerDelegate process_manager_delegate_;
   TestExtensionsBrowserClient extensions_browser_client_;
 
   DISALLOW_COPY_AND_ASSIGN(ProcessManagerTest);
 };
 
 // Test that notification registration works properly.
 TEST_F(ProcessManagerTest, ExtensionNotificationRegistration) {
   // Test for a normal context ProcessManager.
   scoped_ptr<ProcessManager> manager1(
       ProcessManager::Create(original_context()));
@@ skipping 44 matching lines @@
   EXPECT_FALSE(IsRegistered(manager2.get(),
                             chrome::NOTIFICATION_EXTENSIONS_READY,
                             original_context()));
 
   // This notification is observed for incognito contexts only.
   EXPECT_TRUE(IsRegistered(manager2.get(),
                            chrome::NOTIFICATION_PROFILE_DESTROYED,
                            incognito_context()));
 }
 
+// Test that startup background hosts are created when the extension system
+// becomes ready.
+//
+// NOTE: This test and those that follow do not try to create ExtensionsHosts
+// because ExtensionHost is tightly coupled to WebContents and can't be
+// constructed in unit tests.
+TEST_F(ProcessManagerTest, CreateBackgroundHostsOnExtensionsReady) {
+  scoped_ptr<ProcessManager> manager(
+      ProcessManager::Create(original_context()));
+  ASSERT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // Simulate the extension system becoming ready.
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_EXTENSIONS_READY,
+      content::Source<BrowserContext>(original_context()),
+      content::NotificationService::NoDetails());
+  EXPECT_TRUE(manager->startup_background_hosts_created_for_test());
+}
+
+// Test that startup background hosts can be created explicitly before the
+// extension system is ready (this is the normal pattern in Chrome).
+TEST_F(ProcessManagerTest, CreateBackgroundHostsExplicitly) {
+  scoped_ptr<ProcessManager> manager(
+      ProcessManager::Create(original_context()));
+  ASSERT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // Embedder explicitly asks for hosts to be created. Chrome does this on
+  // normal startup.
+  manager->MaybeCreateStartupBackgroundHosts();
+  EXPECT_TRUE(manager->startup_background_hosts_created_for_test());
+
+  // Simulate the extension system becoming ready. Nothing changes.
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_EXTENSIONS_READY,
+      content::Source<BrowserContext>(original_context()),
+      content::NotificationService::NoDetails());
+  EXPECT_TRUE(manager->startup_background_hosts_created_for_test());

[Yoyo Zhou, 2014/07/15 02:13:22]

"Nothing changes" - hosts don't get uncreated, right? What does this test that
199 doesn't?

[James Cook, 2014/07/15 17:02:52]

Nothing really, I guess. I was just emulating what Chrome does. Removed.

+}
+
+// Test that the embedder can defer background host creation. Chrome does this
+// when the profile is created asynchronously, which may take a while.
+TEST_F(ProcessManagerTest, CreateBackgroundHostsDeferred) {
+  scoped_ptr<ProcessManager> manager(
+      ProcessManager::Create(original_context()));
+  ASSERT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // Don't create background hosts if the delegate says to defer them.
+  process_manager_delegate_.defer_creating_startup_background_hosts_ = true;
+  manager->MaybeCreateStartupBackgroundHosts();
+  EXPECT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // The extension system becoming ready still doesn't create the hosts.
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_EXTENSIONS_READY,
+      content::Source<BrowserContext>(original_context()),
+      content::NotificationService::NoDetails());
+  EXPECT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // Once the embedder is ready the background hosts can be created.
+  process_manager_delegate_.defer_creating_startup_background_hosts_ = false;
+  manager->MaybeCreateStartupBackgroundHosts();
+  EXPECT_TRUE(manager->startup_background_hosts_created_for_test());
+}
+
+// Test that the embedder can disallow background host creation.
+// Chrome OS does this in guest mode.
+TEST_F(ProcessManagerTest, IsBackgroundHostAllowed) {
+  scoped_ptr<ProcessManager> manager(
+      ProcessManager::Create(original_context()));
+  ASSERT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // Don't create background hosts if the delegate disallows them.
+  process_manager_delegate_.is_background_page_allowed_ = false;
+  manager->MaybeCreateStartupBackgroundHosts();
+  EXPECT_FALSE(manager->startup_background_hosts_created_for_test());
+
+  // The extension system becoming ready still doesn't create the hosts.
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_EXTENSIONS_READY,
+      content::Source<BrowserContext>(original_context()),
+      content::NotificationService::NoDetails());
+  EXPECT_FALSE(manager->startup_background_hosts_created_for_test());
+}
+
 // Test that extensions get grouped in the right SiteInstance (and therefore
 // process) based on their URLs.
 TEST_F(ProcessManagerTest, ProcessGrouping) {
   content::ContentBrowserClient content_browser_client;
   content::SetBrowserClientForTesting(&content_browser_client);
 
   // Extensions in different browser contexts should always be different
   // SiteInstances.
   scoped_ptr<ProcessManager> manager1(
       ProcessManager::Create(original_context()));
@@ skipping 17 matching lines @@
   scoped_refptr<SiteInstance> site21 =
       manager1->GetSiteInstanceForURL(ext2_url1);
   EXPECT_NE(site11, site21);
 
   scoped_refptr<SiteInstance> other_profile_site =
       manager2->GetSiteInstanceForURL(ext1_url1);
   EXPECT_NE(site11, other_profile_site);
 }
 
 }  // namespace extensions