Add WaitForCondition() and use it in ExtensionTestNotificationObserver.

chrome/browser/extensions/extension_test_notification_observer.cc

Index: chrome/browser/extensions/extension_test_notification_observer.cc
diff --git a/chrome/browser/extensions/extension_test_notification_observer.cc b/chrome/browser/extensions/extension_test_notification_observer.cc
index f8b7a6d4ecb1865c55ee1b6a87f2938dac03ba69..01554b296f91c483c4668ed4d628dcd0f0ae4d09 100644
--- a/chrome/browser/extensions/extension_test_notification_observer.cc
+++ b/chrome/browser/extensions/extension_test_notification_observer.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/extensions/extension_test_notification_observer.h"
 
+#include "base/callback_list.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -20,6 +21,37 @@ using extensions::Extension;
 
 namespace {
 
+class ConditionRunLoop {
+ public:
+  typedef base::Callback<bool(void)> ConditionCallback;
+
+  explicit ConditionRunLoop(const ConditionCallback& callback);
+
+  void Wait();
+
+  void Check();
+
+ private:
+  scoped_refptr<content::MessageLoopRunner> message_loop_runner_;
+  ConditionCallback condition_callback_;
+};
+
+ConditionRunLoop::ConditionRunLoop(const ConditionCallback& callback)
+    : message_loop_runner_(new content::MessageLoopRunner),
+      condition_callback_(callback) {}
+
+void ConditionRunLoop::Wait() {
+  if (condition_callback_.Run())
+    return;
+
+  message_loop_runner_->Run();
+}
+
+void ConditionRunLoop::Check() {
+  if (condition_callback_.Run())
+    message_loop_runner_->Quit();
+}
+
 bool HasExtensionPageActionCountReachedTarget(LocationBarTesting* location_bar,
                                               int target_page_action_count) {
   VLOG(1) << "Number of page actions: " << location_bar->PageActionCount();
@@ -35,6 +67,74 @@ bool HasExtensionPageActionVisibilityReachedTarget(
          target_visible_page_action_count;
 }
 
+bool HaveAllExtensionRenderViewHostsFinishedLoading(
+    ExtensionProcessManager* manager) {
+  ExtensionProcessManager::ViewSet all_views = manager->GetAllViews();
+  for (ExtensionProcessManager::ViewSet::const_iterator iter =
+           all_views.begin();
+       iter != all_views.end(); ++iter) {
+    if ((*iter)->IsLoading())
+      return false;
+  }
+  return true;
+}
+
+class NotificationSet : public content::NotificationObserver {
+ public:
+  void Add(int type, const content::NotificationSource& source);
+  void Add(int type);
+
+  // Notified any time an Add()ed notification is received.
+  // The details of the notification are dropped.
+  base::CallbackList<void()>& callback_list() {
+    return callback_list_;
+  }
+
+ private:
+  // content::NotificationObserver:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  content::NotificationRegistrar notification_registrar_;
+  base::CallbackList<void()> callback_list_;
+};
+
+void NotificationSet::Add(
+    int type,
+    const content::NotificationSource& source) {
+  notification_registrar_.Add(this, type, source);
+}
+
+void NotificationSet::Add(int type) {
+  Add(type, content::NotificationService::AllSources());
+}
+
+void NotificationSet::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  callback_list_.Notify();
+}
+
+void WaitForCondition(
+    const base::Callback<bool(void)>& condition,
+    NotificationSet* notification_set) {
+  ConditionRunLoop run_loop(condition);

[Jeffrey Yasskin, 2013/11/06 03:33:59]

Since this is now the only use of ConditionRunLoop, I think you can inline it
here:

static void QuitIfCallbackTrue(MessageLoopRunner* run_loop,
                        const base::Callback<bool(void)>* condition) {
  if (condition->Run())
    runner->Quit();
}

if (condition.Run())
  return;
scoped_refptr<MessageLoopRunner> run_loop(new MessageLoopRunner);
scoped_ptr<base::CallbackList<void()>::Subscription> subscription =
    notification_set->callback_list().Add(
      base::Bind(&QuitIfCallbackTrue, base::Unretained(run_loop.get()),
                 base::Unretained(&condition)));
run_loop->Run();

[Bernhard Bauer, 2013/11/11 14:37:44]

Done!

+  scoped_ptr<base::CallbackList<void()>::Subscription> subscription =
+      notification_set->callback_list().Add(
+          base::Bind(&ConditionRunLoop::Check, base::Unretained(&run_loop)));
+  run_loop.Wait();
+}
+
+void WaitForCondition(
+    const base::Callback<bool(void)>& condition,
+    int type) {
+  NotificationSet notification_set;

[Jeffrey Yasskin, 2013/11/06 03:33:59]

I think I'd weakly prefer duplicating these two lines at each call site, but
it's not a big deal.

[Bernhard Bauer, 2013/11/11 14:37:44]

Hm... I kind of like having the short cut.

+  notification_set.Add(type);
+  WaitForCondition(condition, &notification_set);
+}
+
 }  // namespace
 
 ExtensionTestNotificationObserver::ExtensionTestNotificationObserver(
@@ -74,57 +174,33 @@ bool ExtensionTestNotificationObserver::WaitForPageActionCountChangeTo(
     int count) {
   LocationBarTesting* location_bar =
       browser_->window()->GetLocationBar()->GetLocationBarForTesting();
-  if (!HasExtensionPageActionCountReachedTarget(location_bar, count)) {
-    content::WindowedNotificationObserver(
-        chrome::NOTIFICATION_EXTENSION_PAGE_ACTION_COUNT_CHANGED,
-        base::Bind(
-            &HasExtensionPageActionCountReachedTarget, location_bar, count))
-        .Wait();
-  }
-  return HasExtensionPageActionCountReachedTarget(location_bar, count);
+  WaitForCondition(
+      base::Bind(
+          &HasExtensionPageActionCountReachedTarget, location_bar, count),
+      chrome::NOTIFICATION_EXTENSION_PAGE_ACTION_COUNT_CHANGED);
+  return true;
 }
 
 bool ExtensionTestNotificationObserver::WaitForPageActionVisibilityChangeTo(
     int count) {
   LocationBarTesting* location_bar =
       browser_->window()->GetLocationBar()->GetLocationBarForTesting();
-  if (!HasExtensionPageActionVisibilityReachedTarget(location_bar, count)) {
-    content::WindowedNotificationObserver(
-        chrome::NOTIFICATION_EXTENSION_PAGE_ACTION_VISIBILITY_CHANGED,
-        base::Bind(&HasExtensionPageActionVisibilityReachedTarget,
-                   location_bar,
-                   count)).Wait();
-  }
-  return HasExtensionPageActionVisibilityReachedTarget(location_bar, count);
+  WaitForCondition(
+      base::Bind(
+          &HasExtensionPageActionVisibilityReachedTarget, location_bar, count),
+      chrome::NOTIFICATION_EXTENSION_PAGE_ACTION_VISIBILITY_CHANGED);
+  return true;
 }
 
 bool ExtensionTestNotificationObserver::WaitForExtensionViewsToLoad() {
   ExtensionProcessManager* manager =
-    extensions::ExtensionSystem::Get(GetProfile())->process_manager();
-  ExtensionProcessManager::ViewSet all_views = manager->GetAllViews();
-  for (ExtensionProcessManager::ViewSet::const_iterator iter =
-         all_views.begin();
-       iter != all_views.end();) {
-    if (!(*iter)->IsLoading()) {
-      ++iter;
-    } else {
-      // Wait for all the extension render view hosts that exist to finish
-      // loading.
-      content::WindowedNotificationObserver observer(
-          content::NOTIFICATION_LOAD_STOP,
-          content::NotificationService::AllSources());
-      observer.AddNotificationType(
-                                   content::NOTIFICATION_WEB_CONTENTS_DESTROYED,
-                                   content::NotificationService::AllSources());
-      observer.Wait();
-
-      // Test activity may have modified the set of extension processes during
-      // message processing, so re-start the iteration to catch added/removed
-      // processes.
-      all_views = manager->GetAllViews();
-      iter = all_views.begin();
-    }
-  }
+      extensions::ExtensionSystem::Get(GetProfile())->process_manager();
+  NotificationSet notification_set;
+  notification_set.Add(content::NOTIFICATION_WEB_CONTENTS_DESTROYED);
+  notification_set.Add(content::NOTIFICATION_LOAD_STOP);
+  WaitForCondition(
+      base::Bind(&HaveAllExtensionRenderViewHostsFinishedLoading, manager),
+      &notification_set);
   return true;
 }