I appreciate your thoughtful comments but we do disagree.
>Is that right? In which case I would say: of course you need to update the tests.
That is right. I think it is bad for you to need to update a test where the input and output are the same. Your mock is there for you to essentially ignore, but now you need to update the test. You now do not know if you introduced a bug.
You are losing out on encapsulation, the test should not know about the internals, generally speaking.
>The dependencies of a function are also inputs of a kind.
Typically that should not be a concern to the caller of the function.
>Is that right? In which case I would say: of course you need to update the tests.
That is right. I think it is bad for you to need to update a test where the input and output are the same. Your mock is there for you to essentially ignore, but now you need to update the test. You now do not know if you introduced a bug.
You are losing out on encapsulation, the test should not know about the internals, generally speaking.
>The dependencies of a function are also inputs of a kind.
Typically that should not be a concern to the caller of the function.