mojo/system/test_utils.h

   1 // Copyright 2013 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 MOJO_SYSTEM_TEST_UTILS_H_
   6 #define MOJO_SYSTEM_TEST_UTILS_H_
   7
   8 #include <stdint.h>
   9
  10 #include "base/callback_forward.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/macros.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/task_runner.h"
  15 #include "base/threading/thread.h"
  16 #include "base/time/time.h"
  17
  18 namespace tracked_objects {
  19 class Location;
  20 }
  21
  22 namespace mojo {
  23 namespace system {
  24 namespace test {
  25
  26 // Posts the given task (to the given task runner) and waits for it to complete.
  27 // (Note: Doesn't spin the current thread's message loop, so if you're careless
  28 // this could easily deadlock.)
  29 void PostTaskAndWait(scoped_refptr<base::TaskRunner> task_runner,
  30                      const tracked_objects::Location& from_here,
  31                      const base::Closure& task);
  32
  33 // A timeout smaller than |TestTimeouts::tiny_timeout()|. Warning: This may lead
  34 // to flakiness, but this is unavoidable if, e.g., you're trying to ensure that
  35 // functions with timeouts are reasonably accurate. We want this to be as small
  36 // as possible without causing too much flakiness.
  37 base::TimeDelta EpsilonTimeout();
  38
  39 // Stopwatch -------------------------------------------------------------------
  40
  41 // A simple "stopwatch" for measuring time elapsed from a given starting point.
  42 class Stopwatch {
  43  public:
  44   Stopwatch() {}
  45   ~Stopwatch() {}
  46
  47   void Start() { start_time_ = base::TimeTicks::Now(); }
  48
  49   base::TimeDelta Elapsed() { return base::TimeTicks::Now() - start_time_; }
  50
  51  private:
  52   base::TimeTicks start_time_;
  53
  54   DISALLOW_COPY_AND_ASSIGN(Stopwatch);
  55 };
  56
  57 // TestIOThread ----------------------------------------------------------------
  58
  59 class TestIOThread {
  60  public:
  61   enum Mode { kAutoStart, kManualStart };
  62   explicit TestIOThread(Mode mode);
  63   // Stops the I/O thread if necessary.
  64   ~TestIOThread();
  65
  66   // |Start()|/|Stop()| should only be called from the main (creation) thread.
  67   // After |Stop()|, |Start()| may be called again to start a new I/O thread.
  68   // |Stop()| may be called even when the I/O thread is not started.
  69   void Start();
  70   void Stop();
  71
  72   void PostTask(const tracked_objects::Location& from_here,
  73                 const base::Closure& task);
  74   void PostTaskAndWait(const tracked_objects::Location& from_here,
  75                        const base::Closure& task);
  76
  77   base::MessageLoopForIO* message_loop() {
  78     return static_cast<base::MessageLoopForIO*>(io_thread_.message_loop());
  79   }
  80
  81   scoped_refptr<base::TaskRunner> task_runner() {
  82     return message_loop()->message_loop_proxy();
  83   }
  84
  85  private:
  86   base::Thread io_thread_;
  87   bool io_thread_started_;
  88
  89   DISALLOW_COPY_AND_ASSIGN(TestIOThread);
  90 };
  91
  92 }  // namespace test
  93 }  // namespace system
  94 }  // namespace mojo
  95
  96 #endif  // MOJO_SYSTEM_TEST_UTILS_H_