Re: [PATCH libgpiod] bindings: python: fix Line.request() crashing

[Jiri Benc <jbenc@xxxxxxx>]

On Fri, 9 Oct 2020 09:40:29 +0200, Bartosz Golaszewski wrote:
> Thanks for the fixes. Could you send me a chunk of code that triggers
> this error so I can make a test-case for it?

It was as simple as this:

import gpiod
c = gpiod.Chip('0')
l = c.get_line(17)
l.request('my')

Latest stable Raspbian (Debian 10.6), Python 3.7.3. It's so basic that
it's puzzling me that nobody has hit it before me. But my patch is
right, see https://docs.python.org/3/c-api/structures.html:

------
METH_VARARGS | METH_KEYWORDS

Methods with these flags must be of type PyCFunctionWithKeywords. The
function expects three parameters: self, args, kwargs where kwargs is a
dictionary of all the keyword arguments or possibly NULL if there are
no keyword arguments.
------

Yet, commit 02a3d0a2ab5e that attempted to fix this states that the
kwds dictionary was an empty dict. Maybe a change in Python C API in
3.7? The Python 3.6 and earlier documentation did not mention the NULL.
I can't find anything in Python release notes, though.

 Jiri