How to fake a generic method call using FakeItEasy?

Question

I am faking an IDbConnection and I want to fake the call to QueryOne<T>() (a Dapperextension) but I get a NullReferenceException when doing so.

Here´s my code:

IDbConnection myConnection = A.Fake<IDbConnection>();


A.CallTo(() => myConnection.QueryOne<MyDto>(A<string>.Ignored,  <IDbConnection>.Ignored, A<IDbTransaction>.Ignored))
.Returns(new MyDto());

Isn't it possible to mock a generic method call in FakeItEasy or why am I getting the exception?

Thanks in advance...

Christian

score 7 · Accepted Answer · edited May 23 '17 at 11:45

7

Since Dapper uses extension methods to supply its functionality and since extension methods are just fancy static methods, I don't think you will be able to get this to work. From what I've read (see this question) FakeItEasy can't intercept a static method.

edited May 23 '17 at 11:45

Community

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answered Jun 08 '12 at 18:34

Rich McCollister

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Indeed, extensions don't play well with unit tests. My advice, use an interface which mimics the dapper calls you make and program against those interfaces making your unit tests easier to write. – Phil Cooper Oct 04 '13 at 19:47

How to fake a generic method call using FakeItEasy?

1 Answers1