In my opinion, I see unit test/integration tests as a way to refactor with confidence. It also gives the added benefit of allowing one to test your application with many different versions of dependent software.
My current project example is porting my Django application to multiple version of both Django and Python. I can now start to make my application work with python3 just by running tests. So yes, some of the tests may be testing things that should always be correct, but it helps in other ways.
My current project example is porting my Django application to multiple version of both Django and Python. I can now start to make my application work with python3 just by running tests. So yes, some of the tests may be testing things that should always be correct, but it helps in other ways.