How to unit test repositories containing complex queries?

Question

User1058130854 posted

I have a question, if we push complex/multi table queries into the repository layer which I agree is where it should belong - how would you go about unit testing this logic without having a database?

I might add, that normally I would have that when unit testing, you would implement a dummy IRepository, or mock the IRepository so that it would return your domain objects, and you would then unit test the controller classes with a mocked repository.

However by pushing complex queries into the repository itself, it makes it difficult to mock - I mean you wouldn't want to reimplement your complex query logic in the mock, which really only leaves testing with a real database connected, which makes it an integration test

Dave

Answer 1

User-837620913 posted

Correct to your last statement that this is an integration test. When reading your question (before I read the body) I said to myself "just use an integration test." If you have setup things correctly, you should be able to swap out a LocalDb implementation in your test project's App.config and attach a database at test run time so you will have known values for the query (see this link:  http://stackoverflow.com/questions/12244495/how-to-set-up-localdb-for-unit-tests-in-visual-studio-2012-and-entity-framework).

Everything doesn't have to be unit tested - especially if you have an integration test covering it. Heck there are parts of your application that you may never test (e.g., the visual layout on pages).

Answer 2

User1058130854 posted

Thanks Darrell, thanks for the link too good stuff