C ++ Gmock - 使用shared_ptr <factoryclass>

时间:2018-02-24 19:46:42

标签: c++ factory factory-pattern googlemock gmock

我是gtest / gmock的新手并尝试在c ++中测试一个简单的函数,该函数有两个指针'm_propBsh_p'和'm_eBsh_p';在一些工厂创建之后,这些指针变得有效,但是我不想涉及工厂类的复杂性和回调。 以下是我想为其编写测试的函数定义:

    std::string Foo::toString(const std::string &indent) const
    {
    ....

    std::string str =
      (m_propBsh_p != nullptr) ? m_propBsh_p -> toString("P-BSH: ") : "-";
    str +=
      (m_eBsh_p != nullptr) ? m_eBsh_p -> toString("E-BSH: ") : "-";

    return str;
  }

因为我只是想测试这个特定的toString函数,所以我只想拥有'm_propBsh_p'和'm_eBsh_p'的有效指针。我正在瞄准/尝试以下内容:

  //Assuming to have mocked class for pointers
  std::shared_ptr<MockedBshClass> m_mockEBsh_p;
  std::shared_ptr<MockedBshClass> m_mockPropBsh_p;

  TEST_F(FooTest, toStringBshInfoPass)
  {
    std::string eBshAndpBshStr = "eBshAndpBshStr";

    ON_CALL(*m_mockPropBsh_p, toString(_)).WillByDefault(Return(eBshAndpBshStr));
    ON_CALL(*m_mockEBsh_p, toString(_)).WillByDefault(Return(eBshAndpBshStr ));
    //EXPECT_CALL((*m_mockPropBsh_p), toString(_)).Times(1);
    //EXPECT_CALL((*m_mockEBsh_p), toString(_)).Times(1);

    //Call mock or some fake function which makes m_propBsh_p & m_eBsh_p valid.
    foo->makePtrValidAgain(); //however this is a complex function which bring more callbacks and complexity and i do not want to call, instead i want to have some fake/mocked function which just gives me valid pointers

    EXPECT_THAT(foo->toString(""),HasSubstr(eBshAndpBshStr+eBshAndpBshStr));
  }

以下是Foo类和指针的位背景:

   Class Foo : fooParent..
   {
   ...
    void makePtrValidAgain();
    std::string toString();
    ..
    typedef std::shared_ptr<BshClass> m_propBsh_p;
    typedef std::shared_ptr<BshClass> m_eBsh_p; 
   ...
   }; 

   void Foo::makePtrValidAgain()
   {
   ...
   auto someFactory = m_dependencyContainer->get<bssh::SomeFactory>();
   assert(someFactory);

   auto nextTask = [this](std::uint32_t dummy){runAfterFoo();};

   m_propBsh_p = someFactory->create(callback, nextTask);
   m_propBsh_p->execute();
   ...
   //and same happens with m_eBsh_p

   return;       
   }

我不确定,使用gmock / gtest避免测试这种简单函数的复杂性的最佳方法是什么,对我来说就是拥有如上所述的有效指针。

1 个答案:

答案 0 :(得分:1)

首先,您的ON_CALL似乎不正确。您嘲笑BshClass,因此您希望对BshClass的方法创建期望(并且toString()不是一个)。你应该模拟一下

ON_CALL(*m_mockEBsh_p, execute())/*stuff to do*/;

回答你的问题:

  1. 如果已经在Foo构造函数中使用了工厂(您将模拟指针传递给m_propBsh_pm_eBsh_p),那么您可以使用std::shared_ptr功能来控制它们是否指向某些内容与否(例如通过reset())。
  2. 否则,从makePtrValidAgain()中提取工厂方法似乎是个好主意 - 这个函数已经有多个职责,它会在它们上创建指针和调用方法。
  3. 我建议像:

       Class Foo : fooParent..
       {
       ...
        void makePtrValidAgain();
        std::string toString();
        ..
        private:
        void resetPointers();
        typedef std::shared_ptr<BshClass> m_propBsh_p;
        typedef std::shared_ptr<BshClass> m_eBsh_p; 
       ...
       }; 
    
       void Foo::makePtrValidAgain()
       {
       ...
       resetPointers(); //if needed
       m_propBsh_p->execute();
       ...
       //and same happens with m_eBsh_p
       }
    
       void resetPointers()
       {
       auto someFactory = m_dependencyContainer->get<bssh::SomeFactory>();
       assert(someFactory);
    
       auto nextTask = [this](std::uint32_t dummy){runAfterFoo();};
    
       m_propBsh_p = someFactory->create(callback, nextTask);
       //also with the other pointer
       //or better pass the pointer to reset as argument if possible
       }
    

    并尽可能在Foo构造函数中调用resetPointers()。或者公开并从UT调用它。这样,问题就会落到第一个选项,m_propBsh_pm_eBsh_p被设置,你可以通过模拟指针从UT访问它们。