base/debug/leak_tracker_unittest.cc

   1 // Copyright (c) 2011 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/leak_tracker.h"
   6 #include "base/memory/scoped_ptr.h"
   7 #include "testing/gtest/include/gtest/gtest.h"
   8
   9 namespace base {
  10 namespace debug {
  11
  12 namespace {
  13
  14 class ClassA {
  15  private:
  16   LeakTracker<ClassA> leak_tracker_;
  17 };
  18
  19 class ClassB {
  20  private:
  21   LeakTracker<ClassB> leak_tracker_;
  22 };
  23
  24 #ifndef ENABLE_LEAK_TRACKER
  25
  26 // If leak tracking is disabled, we should do nothing.
  27 TEST(LeakTrackerTest, NotEnabled) {
  28   EXPECT_EQ(-1, LeakTracker<ClassA>::NumLiveInstances());
  29   EXPECT_EQ(-1, LeakTracker<ClassB>::NumLiveInstances());
  30
  31   // Use scoped_ptr so compiler doesn't complain about unused variables.
  32   scoped_ptr<ClassA> a1(new ClassA);
  33   scoped_ptr<ClassB> b1(new ClassB);
  34   scoped_ptr<ClassB> b2(new ClassB);
  35
  36   EXPECT_EQ(-1, LeakTracker<ClassA>::NumLiveInstances());
  37   EXPECT_EQ(-1, LeakTracker<ClassB>::NumLiveInstances());
  38 }
  39
  40 #else
  41
  42 TEST(LeakTrackerTest, Basic) {
  43   {
  44     ClassA a1;
  45
  46     EXPECT_EQ(1, LeakTracker<ClassA>::NumLiveInstances());
  47     EXPECT_EQ(0, LeakTracker<ClassB>::NumLiveInstances());
  48
  49     ClassB b1;
  50     ClassB b2;
  51
  52     EXPECT_EQ(1, LeakTracker<ClassA>::NumLiveInstances());
  53     EXPECT_EQ(2, LeakTracker<ClassB>::NumLiveInstances());
  54
  55     scoped_ptr<ClassA> a2(new ClassA);
  56
  57     EXPECT_EQ(2, LeakTracker<ClassA>::NumLiveInstances());
  58     EXPECT_EQ(2, LeakTracker<ClassB>::NumLiveInstances());
  59
  60     a2.reset();
  61
  62     EXPECT_EQ(1, LeakTracker<ClassA>::NumLiveInstances());
  63     EXPECT_EQ(2, LeakTracker<ClassB>::NumLiveInstances());
  64   }
  65
  66   EXPECT_EQ(0, LeakTracker<ClassA>::NumLiveInstances());
  67   EXPECT_EQ(0, LeakTracker<ClassB>::NumLiveInstances());
  68 }
  69
  70 // Try some orderings of create/remove to hit different cases in the linked-list
  71 // assembly.
  72 TEST(LeakTrackerTest, LinkedList) {
  73   EXPECT_EQ(0, LeakTracker<ClassB>::NumLiveInstances());
  74
  75   scoped_ptr<ClassA> a1(new ClassA);
  76   scoped_ptr<ClassA> a2(new ClassA);
  77   scoped_ptr<ClassA> a3(new ClassA);
  78   scoped_ptr<ClassA> a4(new ClassA);
  79
  80   EXPECT_EQ(4, LeakTracker<ClassA>::NumLiveInstances());
  81
  82   // Remove the head of the list (a1).
  83   a1.reset();
  84   EXPECT_EQ(3, LeakTracker<ClassA>::NumLiveInstances());
  85
  86   // Remove the tail of the list (a4).
  87   a4.reset();
  88   EXPECT_EQ(2, LeakTracker<ClassA>::NumLiveInstances());
  89
  90   // Append to the new tail of the list (a3).
  91   scoped_ptr<ClassA> a5(new ClassA);
  92   EXPECT_EQ(3, LeakTracker<ClassA>::NumLiveInstances());
  93
  94   a2.reset();
  95   a3.reset();
  96
  97   EXPECT_EQ(1, LeakTracker<ClassA>::NumLiveInstances());
  98
  99   a5.reset();
 100   EXPECT_EQ(0, LeakTracker<ClassA>::NumLiveInstances());
 101 }
 102
 103 TEST(LeakTrackerTest, NoOpCheckForLeaks) {
 104   // There are no live instances of ClassA, so this should do nothing.
 105   LeakTracker<ClassA>::CheckForLeaks();
 106 }
 107
 108 #endif  // ENABLE_LEAK_TRACKER
 109
 110 }  // namespace
 111
 112 }  // namespace debug
 113 }  // namespace base