text: // Copyright (c) 2012 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 "base/compiler_specific.h"
  #include "base/memory/scoped_ptr.h"
  #include "base/message_loop.h"
  #include "content/browser/web_contents/web_contents_impl.h"
  #include "content/browser/renderer_host/test_render_view_host.h"
  #include "content/public/browser/browser_thread.h"
  #include "content/public/browser/web_contents_delegate.h"
  #include "content/test/test_browser_context.h"
  #include "content/test/test_browser_thread.h"
  #include "testing/gtest/include/gtest/gtest.h"
  
  namespace {
  
  class MockWebContentsDelegate : public content::WebContentsDelegate {
   public:
    virtual ~MockWebContentsDelegate() {}
  };
  
  class WebContentsDelegateTest :
      public content::RenderViewHostImplTestHarness {
   public:
    WebContentsDelegateTest()
        : file_user_blocking_thread_(
              content::BrowserThread::FILE_USER_BLOCKING, &message_loop_),
          io_thread_(content::BrowserThread::IO, &message_loop_) {
    }
  
   private:
    content::TestBrowserThread file_user_blocking_thread_;
    content::TestBrowserThread io_thread_;
  };
  
  TEST_F(WebContentsDelegateTest, UnregisterInDestructor) {
    scoped_ptr<WebContentsImpl> contents_a(
        new WebContentsImpl(browser_context_.get(), NULL, MSG_ROUTING_NONE, NULL,
                            NULL, NULL));
    scoped_ptr<WebContentsImpl> contents_b(
        new WebContentsImpl(browser_context_.get(), NULL, MSG_ROUTING_NONE, NULL,
                            NULL, NULL));
    EXPECT_EQ(NULL, contents_a->GetDelegate());
    EXPECT_EQ(NULL, contents_b->GetDelegate());
  
    scoped_ptr<MockWebContentsDelegate> delegate(new MockWebContentsDelegate());
  
    // Setting a delegate should work correctly.
    contents_a->SetDelegate(delegate.get());
    EXPECT_EQ(delegate.get(), contents_a->GetDelegate());
    EXPECT_TRUE(contents_b->GetDelegate() == NULL);
  
    // A delegate can be a delegate to multiple WebContentsImpl.
    contents_b->SetDelegate(delegate.get());
    EXPECT_EQ(delegate.get(), contents_a->GetDelegate());
    EXPECT_EQ(delegate.get(), contents_b->GetDelegate());
  
    // Setting the same delegate multiple times should work correctly.
    contents_b->SetDelegate(delegate.get());
    EXPECT_EQ(delegate.get(), contents_a->GetDelegate());
    EXPECT_EQ(delegate.get(), contents_b->GetDelegate());
  
    // Setting delegate to NULL should work correctly.
    contents_b->SetDelegate(NULL);
    EXPECT_EQ(delegate.get(), contents_a->GetDelegate());
    EXPECT_TRUE(contents_b->GetDelegate() == NULL);
  
    // Destroying the delegate while it is still the delegate for a
    // WebContentsImpl should unregister it.
    contents_b->SetDelegate(delegate.get());
    EXPECT_EQ(delegate.get(), contents_a->GetDelegate());
    EXPECT_EQ(delegate.get(), contents_b->GetDelegate());
    delegate.reset(NULL);
    EXPECT_TRUE(contents_a->GetDelegate() == NULL);
    EXPECT_TRUE(contents_b->GetDelegate() == NULL);
  
    // Destroy the WebContentses and run the message loop to prevent leaks.
    contents_a.reset();
    contents_b.reset();
  }
  
  }  // namespace
  