ios/web/public/test/test_web_thread_bundle.h

   1 // Copyright 2014 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 IOS_WEB_PUBLIC_TEST_TEST_WEB_THREAD_BUNDLE_H_
   6 #define IOS_WEB_PUBLIC_TEST_TEST_WEB_THREAD_BUNDLE_H_
   7
   8 // TestWebThreadBundle is a convenience class for creating a set of
   9 // TestWebThreads in unit tests.  For most tests, it is sufficient to
  10 // just instantiate the TestWebThreadBundle as a member variable.
  11 //
  12 // By default, all of the created TestWebThreads will be backed by a single
  13 // shared MessageLoop. If a test truly needs separate threads, it can do
  14 // so by passing the appropriate combination of RealThreadsMask values during
  15 // the TestWebThreadBundle construction.
  16 //
  17 // The TestWebThreadBundle will attempt to drain the MessageLoop on
  18 // destruction. Sometimes a test needs to drain currently enqueued tasks
  19 // mid-test.
  20 //
  21 // The TestWebThreadBundle will also flush the blocking pool on destruction.
  22 // We do this to avoid memory leaks, particularly in the case of threads posting
  23 // tasks to the blocking pool via PostTaskAndReply. By ensuring that the tasks
  24 // are run while the originating TestBroswserThreads still exist, we prevent
  25 // leakage of PostTaskAndReplyRelay objects. We also flush the blocking pool
  26 // again at the point where it would normally be shut down, to better simulate
  27 // the normal thread shutdown process.
  28 //
  29 // Some tests using the IO thread expect a MessageLoopForIO. Passing
  30 // IO_MAINLOOP will use a MessageLoopForIO for the main MessageLoop.
  31 // Most of the time, this avoids needing to use a REAL_IO_THREAD.
  32
  33 #include "base/macros.h"
  34 #include "base/memory/scoped_ptr.h"
  35
  36 namespace web {
  37
  38 class TestWebThreadBundleImpl;
  39
  40 class TestWebThreadBundle {
  41  public:
  42   // Used to specify the type of MessageLoop that backs the UI thread, and
  43   // which of the named WebThreads should be backed by a real
  44   // threads. The UI thread is always the main thread in a unit test.
  45   enum Options {
  46     DEFAULT = 0x00,
  47     IO_MAINLOOP = 0x01,
  48     REAL_DB_THREAD = 0x02,
  49     REAL_FILE_THREAD = 0x08,
  50     REAL_FILE_USER_BLOCKING_THREAD = 0x10,
  51     REAL_CACHE_THREAD = 0x20,
  52     REAL_IO_THREAD = 0x40,
  53   };
  54
  55   TestWebThreadBundle();
  56   explicit TestWebThreadBundle(int options);
  57
  58   ~TestWebThreadBundle();
  59
  60  private:
  61   scoped_ptr<TestWebThreadBundleImpl> impl_;
  62
  63   DISALLOW_COPY_AND_ASSIGN(TestWebThreadBundle);
  64 };
  65
  66 }  // namespace web
  67
  68 #endif  // IOS_WEB_PUBLIC_TEST_TEST_WEB_THREAD_BUNDLE_H_