Mocking classes which dont have interface and even no virtual methods [duplicate]

Question

I want to mock a particular method of a class, problem i am facing while mocking is that class does not have any interface and also that method is not virtual.

Can any one suggest any other way to implement mocking.

Any help will be appreciated. Thanks in advance

Answer 1

Option 1: TypeMock Isolator or something similar, which allows deeper messing with the code than normal mocking.

Option 2: (Preferred if possible) Alter the design, e.g. by introducing an interface and creating a delegating implementation which just calls into the existing test-unfriendly class. You can then depend on the interface, mock it in tests, and delegate to the "real" implementation for production.

This is assume you really should be mocking the class, of course. You shouldn't automatically mock everything your code uses - I tend to think of mocking "services" of some description, whereas I wouldn't mock (for example) List<T>.

Answer 2

I suggest refactoring your code ;) All mocking frameworks which creates mock by deriving from mocked class requires methods to be virtual (this is more CLR requirement rather than mocking framework).

To mock non-virtual methods you can use profiler-based frameworks like Moles or TypeMock Isolator, however this requires to run test runner using special runner which will attach CLR profiler to process