%nokwargs (and %feature("kwargs", "0")) on an individual function was
silently ignored when the -keyword command line option was set, because
check_kwargs() used GetFlag() which cannot distinguish "feature unset"
from feature value "0". Honour the explicit feature value when set
instead of OR-ing it with use_kw.
Visible under -builtin where the affected function's wrapper now uses
METH_VARARGS instead of METH_VARARGS|METH_KEYWORDS, so calling with
kwargs raises TypeError as expected. Without -builtin, the generated
Python proxy accepts named arguments and forwards them positionally,
masking the C wrapper level rejection - the runmes therefore gate the
TypeError assertions on is_python_builtin().
Add regression test python_nokwargs_keyword (built with -keyword) that
fails on the unfixed code, plus a parallel python_nokwargs_feature that
exercises the same opt-out behaviour via a module-wide %feature("kwargs").
Both cover constructors, instance methods, static methods, and global
functions.
Assisted-by: Claude Opus 4.7
William S Fulton