我可以使用EXPECT_CALL来验证模拟对象的构造函数是否多次调用成员函数吗？

Question

I have a class whose constructor calls a member function, which in turn calls other member functions. I want to use GMock to create a mock class and verify that, when a mock class object is constructed, those member functions were called exactly once each during the construction. But I am observing the following dilemma:

• On one hand, according to GMock's Dummy doc , "Google Mock requires expectations to be set before the mock functions are called, otherwise the behavior is undefined." So you have to call EXPECT_CALL() before the object's constructor is executed.

• On the other hand, EXPECT_CALL() needs an object as its first argument, so we have to construct the object before we can set the expectation.

Is the above observation correct and, if so, is there still a way to achieve what I am hoping to do?

Answer 1

It sounds like you're going to end up testing the Mock of your class, but that's not very helpful. The mocked constructor will not make calls to the member functions by default, so your EXPECT_CALL() 's would need to be paired with forcing the Mock to make those function calls. Not a useful situation to getting your code's behaviour into an automated test harness.

Instead of trying to test the implementation details of your class, can you create the object and use EXPECT calls on the public interface to verify that the constructor has put the object into the correct state?