TestingPlatformSupport: register Platform instance correctly

third_party/WebKit/Source/platform/testing/TestingPlatformSupport.h

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef TestingPlatformSupport_h
 #define TestingPlatformSupport_h
 
+#include "base/logging.h"

[Takashi Toyoshima, 2017/01/11 08:35:19]

removed

 #include "platform/PlatformExport.h"
 #include "platform/WebTaskRunner.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebCompositorSupport.h"
 #include "public/platform/WebScheduler.h"
 #include "public/platform/WebThread.h"
 #include "wtf/Vector.h"
 #include <memory>
 
 namespace base {
@@ skipping 137 matching lines @@
 
  protected:
   static double getTestTime();
 
   std::unique_ptr<base::SimpleTestTickClock> m_clock;
   scoped_refptr<cc::OrderedSimpleTaskRunner> m_mockTaskRunner;
   std::unique_ptr<scheduler::RendererSchedulerImpl> m_scheduler;
   std::unique_ptr<WebThread> m_thread;
 };
 
+template <class T>
+class ScopedTestingPlatformSupport {
+ public:
+  ScopedTestingPlatformSupport() : m_originalPlatform(Platform::current()) {}
+  explicit ScopedTestingPlatformSupport(T* testingPlatformSupport)

[jbroman, 2016/12/22 15:27:54]

Taking ownership by raw pointer, here and below, is something we're trying to
get rid of. Could this take std::unique_ptr instead (and have the callers use
MakeUnique)?

[Takashi Toyoshima, 2017/01/11 08:35:19]

Done.

+      : m_originalPlatform(Platform::current()) {
+    reset(testingPlatformSupport);
+  }
+  void reset(T* testingPlatformSupport) {
+    DCHECK_NE(m_testingPlatformSupport.get(), testingPlatformSupport);
+    if (testingPlatformSupport)
+      Platform::setCurrentPlatformForTesting(testingPlatformSupport);
+    m_testingPlatformSupport.reset(testingPlatformSupport);
+  }
+  ~ScopedTestingPlatformSupport() {
+    m_testingPlatformSupport.reset();
+    if (m_originalPlatform)
+      Platform::setCurrentPlatformForTesting(m_originalPlatform);
+  }
+  const T* operator->() const { return m_testingPlatformSupport.get(); }
+  T* operator->() { return m_testingPlatformSupport.get(); }
+
+ private:
+  Platform* m_originalPlatform;
+  std::unique_ptr<T> m_testingPlatformSupport;
+};
+
 class ScopedUnittestsEnvironmentSetup {
   WTF_MAKE_NONCOPYABLE(ScopedUnittestsEnvironmentSetup);
 
  public:
   ScopedUnittestsEnvironmentSetup(int argc, char** argv);
   ~ScopedUnittestsEnvironmentSetup();
 
  private:
   class DummyPlatform;
   std::unique_ptr<base::TestDiscardableMemoryAllocator>
       m_discardableMemoryAllocator;
   std::unique_ptr<DummyPlatform> m_platform;
   std::unique_ptr<cc_blink::WebCompositorSupportImpl> m_compositorSupport;
   TestingPlatformSupport::Config m_testingPlatformConfig;
-  std::unique_ptr<TestingPlatformSupport> m_testingPlatformSupport;
+  ScopedTestingPlatformSupport<TestingPlatformSupport> m_testingPlatformSupport;
 };
 
 }  // namespace blink
 
 #endif  // TestingPlatformSupport_h