mfbt/tests/TestRefPtr.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/RefPtr.h"
   8 #include "mozilla/RefCounted.h"
   9
  10 using mozilla::RefCounted;
  11
  12 class Foo : public RefCounted<Foo>
  13 {
  14 public:
  15   MOZ_DECLARE_REFCOUNTED_TYPENAME(Foo)
  16
  17   Foo() : mDead(false) {}
  18
  19   static int sNumDestroyed;
  20
  21   ~Foo()
  22   {
  23     MOZ_ASSERT(!mDead);
  24     mDead = true;
  25     sNumDestroyed++;
  26   }
  27
  28 private:
  29   bool mDead;
  30 };
  31 int Foo::sNumDestroyed;
  32
  33 struct Bar : public Foo {};
  34
  35 already_AddRefed<Foo>
  36 NewFoo()
  37 {
  38   RefPtr<Foo> f(new Foo());
  39   return f.forget();
  40 }
  41
  42 already_AddRefed<Foo>
  43 NewBar()
  44 {
  45   RefPtr<Bar> bar = new Bar();
  46   return bar.forget();
  47 }
  48
  49 void
  50 GetNewFoo(Foo** aFoo)
  51 {
  52   *aFoo = new Bar();
  53   // Kids, don't try this at home
  54   (*aFoo)->AddRef();
  55 }
  56
  57 void
  58 GetNewFoo(RefPtr<Foo>* aFoo)
  59 {
  60   *aFoo = new Bar();
  61 }
  62
  63 already_AddRefed<Foo>
  64 GetNullFoo()
  65 {
  66   return 0;
  67 }
  68
  69 int
  70 main()
  71 {
  72   MOZ_RELEASE_ASSERT(0 == Foo::sNumDestroyed);
  73   {
  74     RefPtr<Foo> f = new Foo();
  75     MOZ_RELEASE_ASSERT(f->refCount() == 1);
  76   }
  77   MOZ_RELEASE_ASSERT(1 == Foo::sNumDestroyed);
  78
  79   {
  80     RefPtr<Foo> f1 = NewFoo();
  81     RefPtr<Foo> f2(NewFoo());
  82     MOZ_RELEASE_ASSERT(1 == Foo::sNumDestroyed);
  83   }
  84   MOZ_RELEASE_ASSERT(3 == Foo::sNumDestroyed);
  85
  86   {
  87     RefPtr<Foo> b = NewBar();
  88     MOZ_RELEASE_ASSERT(3 == Foo::sNumDestroyed);
  89   }
  90   MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed);
  91
  92   {
  93     RefPtr<Foo> f1;
  94     {
  95       f1 = new Foo();
  96       RefPtr<Foo> f2(f1);
  97       RefPtr<Foo> f3 = f2;
  98       MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed);
  99     }
 100     MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed);
 101   }
 102   MOZ_RELEASE_ASSERT(5 == Foo::sNumDestroyed);
 103
 104   {
 105     {
 106       RefPtr<Foo> f = new Foo();
 107       RefPtr<Foo> g = f.forget();
 108     }
 109     MOZ_RELEASE_ASSERT(6 == Foo::sNumDestroyed);
 110   }
 111
 112   {
 113     RefPtr<Foo> f = new Foo();
 114     GetNewFoo(getter_AddRefs(f));
 115     MOZ_RELEASE_ASSERT(7 == Foo::sNumDestroyed);
 116   }
 117   MOZ_RELEASE_ASSERT(8 == Foo::sNumDestroyed);
 118
 119   {
 120     RefPtr<Foo> f = new Foo();
 121     GetNewFoo(&f);
 122     MOZ_RELEASE_ASSERT(9 == Foo::sNumDestroyed);
 123   }
 124   MOZ_RELEASE_ASSERT(10 == Foo::sNumDestroyed);
 125
 126   {
 127     RefPtr<Foo> f1 = new Bar();
 128   }
 129   MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed);
 130
 131   {
 132     RefPtr<Foo> f = GetNullFoo();
 133     MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed);
 134   }
 135   MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed);
 136
 137   return 0;
 138 }
 139