Em qui., 24 de mar. de 2022 às 15:39, Fabio Zadrozny <fabiofz@gmail.com> escreveu:
PEP 523 API added more private functions for code objects:

* _PyEval_RequestCodeExtraIndex()
* _PyCode_GetExtra()
* _PyCode_SetExtra()

The _PyEval_RequestCodeExtraIndex() function seems to be used by the
pydevd debugger. The two others seem to be unused in the wild. I'm not
sure if these ones should be moved to the internal C API. They can be
left unchanged, since they don't use a type only defined by the
internal C API.
Just to note, the pydevd/debugpy debuggers actually uses all of those APIs.

i.e.:


The debugger already has workarounds because of changes to evaluation api over time (see: https://github.com/fabioz/PyDev.Debugger/blob/main/_pydevd_frame_eval/pydevd_frame_evaluator.template.pyx#L491) and I know 3.11 won't be different.

I'm ok with changes as I understand that this is a special API -- as long as there's still a way to use it and get the information needed (the debugger already goes through many hops because it needs to use many internals of CPython -- in every new release it's a **really** big task to update to the latest version as almost everything that the debugger relies to make debugging fast changes across versions and I never really know if it'll be possible to support it until I really try to do the port -- I appreciate having less things in a public API so it's easier to have extensions work in other interpreters/not recompiling on newer versions, but please keep it possible to use private APIs which provides the same access that CPython has to access things internally for special cases such as the debugger).

Maybe later on that PEP from mark which allows a better debugger API could alleviate that (but until then, if possible I appreciate it if there's some effort not to break things unless really needed -- ideally with instructions on how to port).

Anyways, to wrap up, the debugger already needs to be built with `Py_BUILD_CORE_MODULE=1` anyways, so, I guess having it in a private API (as long as it's still accessible in that case) is probably not a big issue for the debugger and having setters/getters to set it instead of relying on `state.interp.eval_frame` seems good to me.

Cheers,

Fabio
 

I think the main issue here is the compatibility across the same version though... is it possible to have some kind of guarantee on private APIs that something won't change across micro-releases?

I.e.: having the frame evaluation function change across major releases and having them be reworked seems reasonable, but then having the frame evaluation be changed across micro-releases wouldn't be.

So, I'm ok in pushing things to the internal API, but then I still would like guarantees about the compatibility of that API in the same major release (otherwise those setters/getters/frame evaluation should probably remain on the public API if the related structure was moved to the internal API).

Cheers,

Fabio