FakeItEasy configure fake to throw exception and return value on the next call

Question

We have to implement a retry-mechanism.

To test the RetryProvider, I want a fake of a class to throw exceptions on the first two calls, but return a valid object on the third call.

Under normal circumstances (without throwing exceptions) we could use A.CallTo(() => this.fakeRepo.Get(1)).ReturnsNextFromSequence("a", "b", "c");

I want something similar:

• First Call: throw new Exception();
• Second Call: throw new Exception();
• Third Call: return "success";

How can I configure my fake to do this?

Thanks in advance

Answer 1

var fakeRepo = A.Fake<IFakeRepo>();

A.CallTo(() => fakeRepo.Get(1))
     .Throws<NullReferenceException>()
     .Once()
     .Then
     .Throws<NullReferenceException>()
     .Once()
     .Then
     .Returns('a');

See more about this at Specifying different behaviors for successive calls.