base/debug/trace_event_system_stats_monitor_unittest.cc

   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 #include "base/debug/trace_event_system_stats_monitor.h"
   6
   7 #include <sstream>
   8 #include <string>
   9
  10 #include "base/debug/trace_event_impl.h"
  11 #include "base/message_loop/message_loop.h"
  12 #include "testing/gtest/include/gtest/gtest.h"
  13
  14 namespace base {
  15 namespace debug {
  16
  17 #if !defined(OS_IOS)
  18 // Tests for the system stats monitor.
  19 // Exists as a class so it can be a friend of TraceEventSystemStatsMonitor.
  20 class TraceSystemStatsMonitorTest : public testing::Test {
  21  public:
  22   TraceSystemStatsMonitorTest() {}
  23   virtual ~TraceSystemStatsMonitorTest() {}
  24
  25  private:
  26   DISALLOW_COPY_AND_ASSIGN(TraceSystemStatsMonitorTest);
  27 };
  28
  29 //////////////////////////////////////////////////////////////////////////////
  30
  31 TEST_F(TraceSystemStatsMonitorTest, TraceEventSystemStatsMonitor) {
  32   MessageLoop message_loop;
  33
  34   // Start with no observers of the TraceLog.
  35   EXPECT_EQ(0u, TraceLog::GetInstance()->GetObserverCountForTest());
  36
  37   // Creating a system stats monitor adds it to the TraceLog observer list.
  38   scoped_ptr<TraceEventSystemStatsMonitor> system_stats_monitor(
  39       new TraceEventSystemStatsMonitor(
  40           message_loop.message_loop_proxy()));
  41   EXPECT_EQ(1u, TraceLog::GetInstance()->GetObserverCountForTest());
  42   EXPECT_TRUE(
  43       TraceLog::GetInstance()->HasEnabledStateObserver(
  44           system_stats_monitor.get()));
  45
  46   // By default the observer isn't dumping memory profiles.
  47   EXPECT_FALSE(system_stats_monitor->IsTimerRunningForTest());
  48
  49   // Simulate enabling tracing.
  50   system_stats_monitor->StartProfiling();
  51   message_loop.RunUntilIdle();
  52   EXPECT_TRUE(system_stats_monitor->IsTimerRunningForTest());
  53
  54   // Simulate disabling tracing.
  55   system_stats_monitor->StopProfiling();
  56   message_loop.RunUntilIdle();
  57   EXPECT_FALSE(system_stats_monitor->IsTimerRunningForTest());
  58
  59   // Deleting the observer removes it from the TraceLog observer list.
  60   system_stats_monitor.reset();
  61   EXPECT_EQ(0u, TraceLog::GetInstance()->GetObserverCountForTest());
  62 }
  63 #endif  // !defined(OS_IOS)
  64
  65 }  // namespace debug
  66 }  // namespace base