Why use- and learn Unit/NUnit testing?

Unfortunately, most nunit tests are not seeing written as real unit tests. nunit or any other automation will get full benefit if they use object mocking. So as of this mocking you can still test your unit of work if any other layer is down. e.g. if you test a method of Business Layer, you only test it and any calls to Data Access Layer won't test as part of this unit testing. If you test both BL and DAL, then it's integration testing, not unit testing.

 

Your BL unit test should pass even if DAL layer is down...That's the expectation. So in your nunit test of BL, you won't use real DAL objects, but a mock of DAL layer. So in each and every build your tests will pass without depending on any other layers. So for isolated unit testing, you need a test script framework + a mocking framework(this part many missed)

 

Frameworks like nunit will contribute towards other automation areas in devops. Its all beyond scope of this single post. But please check mocking frameworks lilke rhino mocks and also check devops