coverage report might raise FileNotFoundError when test patches glob

[itamaro]

coverage report might raise FileNotFoundError when test patches glob

[nedbat]

I am upgrading the "one and only version of coverage" in the Meta monorepo

Wow, OK! Let me know if other issues arise.

[nedbat]

I would rather not try to make coverage defensive against aggressive monkeypatching in tests. How hard would it be to update the test? If you could patch the fake implementation where you use glob instead of in the glob module itself, it will have a more localized effect.

[itamaro]

How hard would it be to update the test?

That's definitely the right thing to do :)

I'm sure it's not that hard to fix the specific test (it will require overhauling the patching strategy in that test though).
For context, I am upgrading the "one and only version of coverage" in the Meta monorepo, so I am not an expert on most of the millions of the affected tests.

If you could patch the fake implementation where you use glob instead of in the glob module itself, it will have a more localized effect.

looks like the test was actually trying to do that. glob was being imported in app/util.py, and the test was patching app.util.glob.glob. I guess this is one of those mock footguns, where the right thing to patch was app.util.glob, and patching app.util.glob.glob actually patches the glob function in the builtin glob module.
Interestingly, even calling mocked_glob.stop() doesn't unpatch the builtin glob.glob... but that's definitely out of scope for a coverage-specific issue :)

In any case, I'm totally ok with this being closed as "not a bug" / "user doing clowny things"!