path: root/xpcom/tests/gtest/TestNsRefPtr.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/RefPtr.h"
#include "nsCOMPtr.h"
#include "nsISupports.h"
#include "nsQueryObject.h"
#include "mozilla/Unused.h"

#include "gtest/gtest.h"

namespace TestNsRefPtr {

#define NS_FOO_IID                                   \
  {                                                  \
    0x6f7652e0, 0xee43, 0x11d1, {                    \
      0x9c, 0xc3, 0x00, 0x60, 0x08, 0x8c, 0xa6, 0xb3 \
    }                                                \
  }

class Foo : public nsISupports {
 public:
  NS_DECLARE_STATIC_IID_ACCESSOR(NS_FOO_IID)

 public:
  Foo();
  // virtual dtor because Bar uses our Release()
  virtual ~Foo();

  NS_IMETHOD_(MozExternalRefCountType) AddRef() override;
  NS_IMETHOD_(MozExternalRefCountType) Release() override;
  NS_IMETHOD QueryInterface(const nsIID&, void**) override;
  void MemberFunction(int, int*, int&);
  virtual void VirtualMemberFunction(int, int*, int&);
  virtual void VirtualConstMemberFunction(int, int*, int&) const;

  void NonconstMethod() {}
  void ConstMethod() const {}

  int refcount_;

  static int total_constructions_;
  static int total_destructions_;
  static int total_addrefs_;
  static int total_queries_;
};

NS_DEFINE_STATIC_IID_ACCESSOR(Foo, NS_FOO_IID)

int Foo::total_constructions_;
int Foo::total_destructions_;
int Foo::total_addrefs_;
int Foo::total_queries_;

Foo::Foo() : refcount_(0) { ++total_constructions_; }

Foo::~Foo() { ++total_destructions_; }

MozExternalRefCountType Foo::AddRef() {
  ++refcount_;
  ++total_addrefs_;
  return refcount_;
}

MozExternalRefCountType Foo::Release() {
  int newcount = --refcount_;
  if (newcount == 0) {
    delete this;
  }

  return newcount;
}

nsresult Foo::QueryInterface(const nsIID& aIID, void** aResult) {
  ++total_queries_;

  nsISupports* rawPtr = 0;
  nsresult status = NS_OK;

  if (aIID.Equals(NS_GET_IID(Foo)))
    rawPtr = this;
  else {
    nsID iid_of_ISupports = NS_ISUPPORTS_IID;
    if (aIID.Equals(iid_of_ISupports))
      rawPtr = static_cast<nsISupports*>(this);
    else
      status = NS_ERROR_NO_INTERFACE;
  }

  NS_IF_ADDREF(rawPtr);
  *aResult = rawPtr;

  return status;
}

void Foo::MemberFunction(int aArg1, int* aArgPtr, int& aArgRef) {}

void Foo::VirtualMemberFunction(int aArg1, int* aArgPtr, int& aArgRef) {}

void Foo::VirtualConstMemberFunction(int aArg1, int* aArgPtr,
                                     int& aArgRef) const {}

static nsresult CreateFoo(void** result)
// a typical factory function (that calls AddRef)
{
  auto* foop = new Foo;

  foop->AddRef();
  *result = foop;

  return NS_OK;
}

static void set_a_Foo(RefPtr<Foo>* result) {
  assert(result);

  RefPtr<Foo> foop(do_QueryObject(new Foo));
  *result = foop;
}

static RefPtr<Foo> return_a_Foo() {
  RefPtr<Foo> foop(do_QueryObject(new Foo));
  return foop;
}

#define NS_BAR_IID                                   \
  {                                                  \
    0x6f7652e1, 0xee43, 0x11d1, {                    \
      0x9c, 0xc3, 0x00, 0x60, 0x08, 0x8c, 0xa6, 0xb3 \
    }                                                \
  }

class Bar : public Foo {
 public:
  NS_DECLARE_STATIC_IID_ACCESSOR(NS_BAR_IID)

 public:
  Bar();
  ~Bar() override;

  NS_IMETHOD QueryInterface(const nsIID&, void**) override;

  void VirtualMemberFunction(int, int*, int&) override;
  void VirtualConstMemberFunction(int, int*, int&) const override;

  static int total_constructions_;
  static int total_destructions_;
  static int total_queries_;
};

NS_DEFINE_STATIC_IID_ACCESSOR(Bar, NS_BAR_IID)

int Bar::total_constructions_;
int Bar::total_destructions_;
int Bar::total_queries_;

Bar::Bar() { ++total_constructions_; }

Bar::~Bar() { ++total_destructions_; }

nsresult Bar::QueryInterface(const nsID& aIID, void** aResult) {
  ++total_queries_;

  nsISupports* rawPtr = 0;
  nsresult status = NS_OK;

  if (aIID.Equals(NS_GET_IID(Bar)))
    rawPtr = this;
  else if (aIID.Equals(NS_GET_IID(Foo)))
    rawPtr = static_cast<Foo*>(this);
  else {
    nsID iid_of_ISupports = NS_ISUPPORTS_IID;
    if (aIID.Equals(iid_of_ISupports))
      rawPtr = static_cast<nsISupports*>(this);
    else
      status = NS_ERROR_NO_INTERFACE;
  }

  NS_IF_ADDREF(rawPtr);
  *aResult = rawPtr;

  return status;
}

void Bar::VirtualMemberFunction(int aArg1, int* aArgPtr, int& aArgRef) {}
void Bar::VirtualConstMemberFunction(int aArg1, int* aArgPtr,
                                     int& aArgRef) const {}

}  // namespace TestNsRefPtr

using namespace TestNsRefPtr;

TEST(nsRefPtr, AddRefAndRelease)
{
  Foo::total_constructions_ = 0;
  Foo::total_destructions_ = 0;

  {
    RefPtr<Foo> foop(do_QueryObject(new Foo));
    ASSERT_EQ(Foo::total_constructions_, 1);
    ASSERT_EQ(Foo::total_destructions_, 0);
    ASSERT_EQ(foop->refcount_, 1);

    foop = do_QueryObject(new Foo);
    ASSERT_EQ(Foo::total_constructions_, 2);
    ASSERT_EQ(Foo::total_destructions_, 1);

    // [Shouldn't compile] Is it a compile time error to try to |AddRef| by
    // hand?
    // foop->AddRef();

    // [Shouldn't compile] Is it a compile time error to try to |Release| be
    // hand?
    // foop->Release();

    // [Shouldn't compile] Is it a compile time error to try to |delete| an
    // |nsCOMPtr|?
    // delete foop;

    static_cast<Foo*>(foop)->AddRef();
    ASSERT_EQ(foop->refcount_, 2);

    static_cast<Foo*>(foop)->Release();
    ASSERT_EQ(foop->refcount_, 1);
  }

  ASSERT_EQ(Foo::total_destructions_, 2);

  {
    RefPtr<Foo> fooP(do_QueryObject(new Foo));
    ASSERT_EQ(Foo::total_constructions_, 3);
    ASSERT_EQ(Foo::total_destructions_, 2);
    ASSERT_EQ(fooP->refcount_, 1);

    Foo::total_addrefs_ = 0;
    RefPtr<Foo> fooP2 = std::move(fooP);
    mozilla::Unused << fooP2;
    ASSERT_EQ(Foo::total_addrefs_, 0);
  }
}

TEST(nsRefPtr, VirtualDestructor)
{
  Bar::total_destructions_ = 0;

  {
    RefPtr<Foo> foop(do_QueryObject(new Bar));
    mozilla::Unused << foop;
  }

  ASSERT_EQ(Bar::total_destructions_, 1);
}

TEST(nsRefPtr, Equality)
{
  Foo::total_constructions_ = 0;
  Foo::total_destructions_ = 0;

  {
    RefPtr<Foo> foo1p(do_QueryObject(new Foo));
    RefPtr<Foo> foo2p(do_QueryObject(new Foo));

    ASSERT_EQ(Foo::total_constructions_, 2);
    ASSERT_EQ(Foo::total_destructions_, 0);

    ASSERT_NE(foo1p, foo2p);

    ASSERT_NE(foo1p, nullptr);
    ASSERT_NE(nullptr, foo1p);
    ASSERT_FALSE(foo1p == nullptr);
    ASSERT_FALSE(nullptr == foo1p);

    ASSERT_NE(foo1p, foo2p.get());

    foo1p = foo2p;

    ASSERT_EQ(Foo::total_constructions_, 2);
    ASSERT_EQ(Foo::total_destructions_, 1);
    ASSERT_EQ(foo1p, foo2p);

    ASSERT_EQ(foo2p, foo2p.get());

    ASSERT_EQ(RefPtr<Foo>(foo2p.get()), foo2p);

    ASSERT_TRUE(foo1p);
  }

  ASSERT_EQ(Foo::total_constructions_, 2);
  ASSERT_EQ(Foo::total_destructions_, 2);
}

TEST(nsRefPtr, AddRefHelpers)
{
  Foo::total_addrefs_ = 0;

  {
    auto* raw_foo1p = new Foo;
    raw_foo1p->AddRef();

    auto* raw_foo2p = new Foo;
    raw_foo2p->AddRef();

    ASSERT_EQ(Foo::total_addrefs_, 2);

    RefPtr<Foo> foo1p(dont_AddRef(raw_foo1p));

    ASSERT_EQ(Foo::total_addrefs_, 2);

    RefPtr<Foo> foo2p;
    foo2p = dont_AddRef(raw_foo2p);

    ASSERT_EQ(Foo::total_addrefs_, 2);
  }

  {
    // Test that various assignment helpers compile.
    RefPtr<Foo> foop;
    CreateFoo(RefPtrGetterAddRefs<Foo>(foop));
    CreateFoo(getter_AddRefs(foop));
    set_a_Foo(address_of(foop));
    foop = return_a_Foo();
  }
}

TEST(nsRefPtr, QueryInterface)
{
  Foo::total_queries_ = 0;
  Bar::total_queries_ = 0;

  {
    RefPtr<Foo> fooP;
    fooP = do_QueryObject(new Foo);
    ASSERT_EQ(Foo::total_queries_, 1);
  }

  {
    RefPtr<Foo> fooP;
    fooP = do_QueryObject(new Foo);
    ASSERT_EQ(Foo::total_queries_, 2);

    RefPtr<Foo> foo2P;
    foo2P = fooP;
    ASSERT_EQ(Foo::total_queries_, 2);
  }

  {
    RefPtr<Bar> barP(do_QueryObject(new Bar));
    ASSERT_EQ(Bar::total_queries_, 1);

    RefPtr<Foo> fooP(do_QueryObject(barP));
    ASSERT_TRUE(fooP);
    ASSERT_EQ(Foo::total_queries_, 2);
    ASSERT_EQ(Bar::total_queries_, 2);
  }
}

// -------------------------------------------------------------------------
// TODO(ER): The following tests should be moved to MFBT.

#define NS_INLINE_DECL_THREADSAFE_MUTABLE_REFCOUNTING(_class)    \
 public:                                                         \
  NS_METHOD_(MozExternalRefCountType) AddRef(void) const {       \
    MOZ_ASSERT_TYPE_OK_FOR_REFCOUNTING(_class)                   \
    MOZ_RELEASE_ASSERT(int32_t(mRefCnt) >= 0, "illegal refcnt"); \
    nsrefcnt count = ++mRefCnt;                                  \
    return (nsrefcnt)count;                                      \
  }                                                              \
  NS_METHOD_(MozExternalRefCountType) Release(void) const {      \
    MOZ_RELEASE_ASSERT(int32_t(mRefCnt) > 0, "dup release");     \
    nsrefcnt count = --mRefCnt;                                  \
    if (count == 0) {                                            \
      delete (this);                                             \
      return 0;                                                  \
    }                                                            \
    return count;                                                \
  }                                                              \
                                                                 \
 protected:                                                      \
  mutable ::mozilla::ThreadSafeAutoRefCnt mRefCnt;               \
                                                                 \
 public:

class ObjectForConstPtr {
 private:
  // Reference-counted classes cannot have public destructors.
  ~ObjectForConstPtr() = default;

 public:
  NS_INLINE_DECL_THREADSAFE_MUTABLE_REFCOUNTING(ObjectForConstPtr)
  void ConstMemberFunction(int aArg1, int* aArgPtr, int& aArgRef) const {}
};
#undef NS_INLINE_DECL_THREADSAFE_MUTABLE_REFCOUNTING

namespace TestNsRefPtr {
static void AnFooPtrPtrContext(Foo**) {}
static void AVoidPtrPtrContext(void**) {}
}  // namespace TestNsRefPtr

TEST(nsRefPtr, RefPtrCompilationTests)
{
  {
    RefPtr<Foo> fooP;

    AnFooPtrPtrContext(getter_AddRefs(fooP));
    AVoidPtrPtrContext(getter_AddRefs(fooP));
  }

  {
    RefPtr<Foo> fooP(new Foo);
    RefPtr<const Foo> constFooP = fooP;
    constFooP->ConstMethod();

    // [Shouldn't compile] Is it a compile time error to call a non-const method
    // on an |RefPtr<const T>|?
    // constFooP->NonconstMethod();

    // [Shouldn't compile] Is it a compile time error to construct an |RefPtr<T>
    // from an |RefPtr<const T>|?
    // RefPtr<Foo> otherFooP(constFooP);
  }

  {
    RefPtr<Foo> foop = new Foo;
    RefPtr<Foo> foop2 = new Bar;
    RefPtr<const ObjectForConstPtr> foop3 = new ObjectForConstPtr;
    int test = 1;
    void (Foo::*fPtr)(int, int*, int&) = &Foo::MemberFunction;
    void (Foo::*fVPtr)(int, int*, int&) = &Foo::VirtualMemberFunction;
    void (Foo::*fVCPtr)(int, int*, int&) const =
        &Foo::VirtualConstMemberFunction;
    void (ObjectForConstPtr::*fCPtr2)(int, int*, int&) const =
        &ObjectForConstPtr::ConstMemberFunction;

    (foop->*fPtr)(test, &test, test);
    (foop2->*fVPtr)(test, &test, test);
    (foop2->*fVCPtr)(test, &test, test);
    (foop3->*fCPtr2)(test, &test, test);
  }

  // Looks like everything ran.
  ASSERT_TRUE(true);
}