Deprecate functions from PEP 623

[konstin]

I think those are all the remaining functions scheduled for removal by PEP 623

[davidhewitt]

I think we should maybe use #[deprecated] to match Python? Just in case some user wants to use these apis.

[kngwyu]

I think #[cfg_attr(Py_3_9, deprecated)] or just #[cfg(not(Py_3_9))] is sufficient.

[konstin]

I've deprecated them unconditionally and cfg'ed them out with a (not yet existing) Py_3_12, as they'd only cause linker errors on those platforms anyway.

[davidhewitt]

In the other deprecations in this patch release we're using #[cfg_attr(Py_3_9, deprecated)].

I think I'm ok with just straight-up #[deprecated] on these APIs, because they're intended for removal with no replacement. Many of the deprecated methods only have their replacement added on the same Python version.

[konstin]

I think I'm ok with just straight-up #[deprecated] on these APIs, because they're intended for removal with no replacement. Many of the deprecated methods only have their replacement added on the same Python version.

Yep, as I understood https://docs.python.org/3/c-api/unicode.html and PEP 623 those methods were legacy for some time already:

PEP 393 was implemented in Python 3.3 which is released in 2012. Old APIs were deprecated since then, and the removal was scheduled in Python 4.0.

Python 4.0 was expected as next version of Python 3.9 when PEP 393 was accepted. But the next version of Python 3.9 is Python 3.10, not 4.0. This is why this PEP schedule the removal plan again.

[davidhewitt]

To get the release moving I'm going to force-push a fix for the commit and merge this. Thanks very much!