> Unit testing private methods. Adding the single biggest reason I have encountered: Because the overall functionality is too complex to test through the API a

> Unit testing private methods. Adding the single biggest reason I have encountered: Because the overall functionality is too complex to test through the API alone, so the alternative is to extract part of the "private" functionality to a separate class that would then be public itself, making functionality public that shouldn't be. By that, the discussion about "testing private methods" ignores the elephant in the room, which is that the language used doesn't have a rich concept of public vs. private in the first place. As evidence for that I'd like to mention that I never had that problem in Rust, because I can simply extract the private functionality into helper functions within a private sub-module and unit-test them there, without that functionality becoming public to the rest of the code.