Why am I getting an Exception with the message “Invalid setup on a non-virtual (overridable in VB) member…”?

Question

I have a unit test where I have to mock a non-virtual method that returns a bool type

public class XmlCupboardAccess
{
    public bool IsDataEntityInXmlCupbo         


        

Answer 1

You'll get this error as well if you are verifying that an extension method of an interface is called.

For example if you are mocking:

var mockValidator = new Mock>();
mockValidator
  .Verify(validator => validator.ValidateAndThrow(foo, null));

You will get the same exception because .ValidateAndThrow() is an extension on the IValidator interface.

public static void ValidateAndThrow(this IValidator validator, T instance, string ruleSet = null)...