Web MIDI: introduce MidiManager::Shutdown to shutdown gracefully

media/midi/midi_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 "media/midi/midi_manager.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/system_monitor/system_monitor.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace media {
 namespace midi {
 
 namespace {
 
 class FakeMidiManager : public MidiManager {
  public:
-  FakeMidiManager() : start_initialization_is_called_(false) {}
+  FakeMidiManager()
+      : start_initialization_is_called_(false), finalize_is_called_(false) {}
   ~FakeMidiManager() override {}
 
   // MidiManager implementation.
   void StartInitialization() override {
     start_initialization_is_called_ = true;
   }
 
+  void Finalize() override { finalize_is_called_ = true; }
+
   void DispatchSendMidiData(MidiManagerClient* client,
                             uint32 port_index,
                             const std::vector<uint8>& data,
                             double timestamp) override {}
 
   // Utility functions for testing.
   void CallCompleteInitialization(Result result) {
     CompleteInitialization(result);
   }
 
   size_t GetClientCount() const {
     return clients_size_for_testing();
   }
 
   size_t GetPendingClientCount() const {
     return pending_clients_size_for_testing();
   }
 
   bool start_initialization_is_called_;
+  bool finalize_is_called_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FakeMidiManager);
 };
 
 class FakeMidiManagerClient : public MidiManagerClient {
  public:
   FakeMidiManagerClient()
       : result_(Result::NOT_SUPPORTED), wait_for_result_(true) {}
   ~FakeMidiManagerClient() override {}
@@ skipping 31 matching lines @@
   bool wait_for_result_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeMidiManagerClient);
 };
 
 class MidiManagerTest : public ::testing::Test {
  public:
   MidiManagerTest()
       : manager_(new FakeMidiManager),
         message_loop_(new base::MessageLoop) {}
-  ~MidiManagerTest() override {}
+  ~MidiManagerTest() override {
+    manager_->Shutdown();
+    base::RunLoop run_loop;
+    run_loop.RunUntilIdle();
+    EXPECT_EQ(manager_->start_initialization_is_called_,
+              manager_->finalize_is_called_);
+  }
 
  protected:
   void StartTheFirstSession(FakeMidiManagerClient* client) {
     EXPECT_FALSE(manager_->start_initialization_is_called_);
     EXPECT_EQ(0U, manager_->GetClientCount());
     EXPECT_EQ(0U, manager_->GetPendingClientCount());
     manager_->StartSession(client);
     EXPECT_EQ(0U, manager_->GetClientCount());
     EXPECT_EQ(1U, manager_->GetPendingClientCount());
     EXPECT_TRUE(manager_->start_initialization_is_called_);
@@ skipping 83 matching lines @@
 // sessions with multiple client_id.
 
 TEST_F(MidiManagerTest, TooManyPendingSessions) {
   // Push as many client requests for starting session as possible.
   ScopedVector<FakeMidiManagerClient> many_existing_clients;
   many_existing_clients.resize(MidiManager::kMaxPendingClientCount);
   for (size_t i = 0; i < MidiManager::kMaxPendingClientCount; ++i) {
     many_existing_clients[i] = new FakeMidiManagerClient;
     StartTheNthSession(many_existing_clients[i], i + 1);
   }
+  EXPECT_TRUE(manager_->start_initialization_is_called_);
 
   // Push the last client that should be rejected for too many pending requests.
   scoped_ptr<FakeMidiManagerClient> additional_client(
       new FakeMidiManagerClient);
   manager_->start_initialization_is_called_ = false;
   manager_->StartSession(additional_client.get());
   EXPECT_FALSE(manager_->start_initialization_is_called_);
+  manager_->start_initialization_is_called_ = true;
   EXPECT_EQ(Result::INITIALIZATION_ERROR, additional_client->result());
 
   // Other clients still should not receive a result.
   RunLoopUntilIdle();
   for (size_t i = 0; i < many_existing_clients.size(); ++i)
     EXPECT_EQ(Result::NOT_SUPPORTED, many_existing_clients[i]->result());
 
   // The Result::OK should be distributed to other clients.
   CompleteInitialization(Result::OK);
   for (size_t i = 0; i < many_existing_clients.size(); ++i)
@@ skipping 36 matching lines @@
   // Do not change the condition for disabling this test.
 #if !defined(OS_MACOSX) && !defined(OS_WIN) && \
     !(defined(USE_ALSA) && defined(USE_UDEV)) && !defined(OS_ANDROID)
   EXPECT_EQ(Result::NOT_SUPPORTED, result);
 #elif defined(USE_ALSA)
   // Temporary until http://crbug.com/371230 is resolved.
   EXPECT_TRUE(result == Result::OK || result == Result::INITIALIZATION_ERROR);
 #else
   EXPECT_EQ(Result::OK, result);
 #endif
+
+  manager->Shutdown();
+  base::RunLoop run_loop;
+  run_loop.RunUntilIdle();
 }
 
+// TODO(toyoshim): Add multi-threaded unit tests to check races around
+// StartInitialization(), CompleteInitialization(), and Finalize().
+
 }  // namespace
 
 }  // namespace midi
 }  // namespace media