There is a mixture of pytest & Python unittest in here. We adopted pytest later on but didn't migrate existing tests (since they still work). New tests should be written using pytest only.
test_xxx.py: Unittests for thexxxmodule in the main repo codebase. Modules that are in subdirs normalize the/into_. For example, test_error.py is for the error.py module, and test_subcmds_forall.py is for the subcmds/forall.py module.- conftest.py: Custom pytest fixtures for sharing.
- utils_for_test.py: Helpers for sharing in tests.