Add tests?

[mgorny]

Given that the standard library includes tests for the tarfile module, could we also have tests for this package?

[jaraco]

Yes, perhaps. That would involve porting another module and maintaining its synchronization here.

My initial instinct was that between CPython testing the code upstream on the latest Python and jaraco.context exercising the behavior downstream for older Pythons that it wouldn't add a lot of value to port the whole test suite for the module. This port does provide nominal tests (tests syntax and any doctests).

Can you tell me more about the value you'd derive from including the full test suite for the module?

[mgorny]

Well, my idea is that if you're taking the module from newer CPython, then it may depend on newer API/behavior of other modules from newer CPython, and this wouldn't show unless you thoroughly tested the complete functionality.

[jaraco]

It was several hours of work, but it's done. Tests are now ported and validating the behavior. There was one bug uncovered by the effort (b572934). In retrospect, it would have been cheaper and easier to just let users discover the bug and report it or (more likely) let Python 3.8 sunset without anyone noticing. There's going to be more toil too when Python 3.13 comes out and the test harnesses and fixtures change again.

[mgorny]

Thanks! I'm sorry to hear it was that much work, but also glad that it turned out that I was right.