of the previous monolithic setup-create-run sequence, that was apparently
inherited from a previous test infrastructure, but makes working with the
tests and adding new ones weird.
Error messages from PL/Python now always mention the function name in the
CONTEXT: field. This also obsoletes the few places that tried to do the
same manually.
Regression test files are updated to work with Python 2.4-2.6. I don't have
access to older versions right now.
python 2.5. This involves fixing several violations of the published
spec for creating PyTypeObjects, and adding another regression test
expected output for yet another variation of error message spelling.