On Saturday, 12 May 2018 at 06:42:24 UTC, rumbu wrote:
Testing private functionality means that you *lock* the internal implementation of your class. If you decide later to change the implementation, your previous tests will have zero-value.
I did TDD at a company for three years. Tests didn't survive refactoring.
These days, I have tests to ensure correctness, and they can tell me when public interfaces change. I usually don't need tests to tell me that, but they help just in case.
I also tend to have examples projects for anything more complex, which reduces the amount of trouble I can get myself into. Plus the majority of my code is in applications rather than libraries, so consistent interfaces aren't nearly as important (as long as static typing catches the majority of incorrect calls and contracts catch the rest).
