chrome/test/base/javascript_test_observer.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_TEST_BASE_JAVASCRIPT_TEST_OBSERVER_H_
   6 #define CHROME_TEST_BASE_JAVASCRIPT_TEST_OBSERVER_H_
   7
   8 #include <string>
   9
  10 #include "base/compiler_specific.h"
  11 #include "content/public/browser/notification_observer.h"
  12 #include "content/public/browser/notification_registrar.h"
  13
  14 namespace base {
  15 class DictionaryValue;
  16 }
  17
  18 namespace content {
  19 class RenderViewHost;
  20 }
  21
  22 // Base class for handling a stream of automation messages produced by a
  23 // JavascriptTestObserver.
  24 class TestMessageHandler {
  25  public:
  26   enum MessageResponse {
  27     // Reset the timeout and keep running.
  28     CONTINUE,
  29     // Stop runnning.
  30     DONE
  31   };
  32
  33   TestMessageHandler();
  34   virtual ~TestMessageHandler();
  35
  36   // Called when a message is received from the DOM automation controller.
  37   virtual MessageResponse HandleMessage(const std::string& json) = 0;
  38
  39   void SetError(const std::string& message);
  40
  41   bool ok() const {
  42     return ok_;
  43   }
  44
  45   const std::string& error_message() const {
  46     return error_message_;
  47   }
  48
  49   // Prepare the handler to be used or reused.
  50   virtual void Reset();
  51
  52  private:
  53   bool ok_;
  54   std::string error_message_;
  55 };
  56
  57 // This class captures a stream of automation messages coming from a Javascript
  58 // test and dispatches them to a message handler.
  59 class JavascriptTestObserver : public content::NotificationObserver {
  60  public:
  61   // The observer does not own any arguments passed to it.  It is assumed that
  62   // the arguments will outlive all uses of the observer.
  63   JavascriptTestObserver(
  64       content::RenderViewHost* render_view_host,
  65       TestMessageHandler* handler);
  66
  67   virtual ~JavascriptTestObserver();
  68
  69   // Pump the message loop until the message handler indicates the Javascript
  70   // test is done running.  Return true if the test jig functioned correctly and
  71   // nothing timed out.
  72   bool Run();
  73
  74   // Prepare the observer to be used again.  This method should NOT be called
  75   // while Run() is pumping the message loop.
  76   void Reset();
  77
  78   virtual void Observe(
  79       int type,
  80       const content::NotificationSource& source,
  81       const content::NotificationDetails& details) OVERRIDE;
  82
  83  private:
  84   // This message did not signal the end of a test, keep going.
  85   void Continue();
  86
  87   // This was the last message we care about, stop listening for more messages.
  88   void EndTest();
  89
  90   TestMessageHandler* handler_;
  91   bool running_;
  92   bool finished_;
  93   content::NotificationRegistrar registrar_;
  94
  95   DISALLOW_COPY_AND_ASSIGN(JavascriptTestObserver);
  96 };
  97
  98 #endif  // CHROME_TEST_BASE_JAVASCRIPT_TEST_OBSERVER_H_