How to Stub a ReadOnly property of a concrete class

Question

Let's say I have a Concrete class with a Read-Only property e.g.

public class TestClass
{
   public bool Squid {get;private set;}
}

And now I want to stub the response to Squid e.g.

Squid squid = MockRepository.GenerateStub<Squid>();
squid.Stub(c => c.Squid).Return(true);

However when I run this I get the following error message: System.InvalidOperationException : Invalid call, the last call has been used or no call has been made (make sure that you are calling a virtual (C#) / Overridable (VB) method).

Is there any way of stubbing this property without creating an interface for the class?

Answer 1

Yes, there is: Make the property virtual as already described in the exception message.

Answer 2

You could use reflection to call the private setter.

Or use reflection to find the backing field and set it directly(A bit harder, but works on non auto-properties with a trivial getter).

And finally it's possible to use the profiling API for that. (AFAIK Moles is based on that).

If any of that is a good idea is a different question...