It seems to vary a lot from school to school. At my university (2010-2014) we were writing unit tests from the first CS class. I can't say we got much instructi

It seems to vary a lot from school to school. At my university (2010-2014) we were writing unit tests from the first CS class. I can't say we got much instruction on how to structure more complex applications in order to make them testable, however. Things like dependency injection and non-trivial mocking have to be learned on the job, which is a real shame. Even within the industry skills and approaches to designing code for tests feel very heterogeneous.