Disable setuptools injection in Python 3.12+ (whenever distutils gets removed from stdlib)

What’s the problem this feature will solve?

Currently, pip invokes setup.py files in a manner that injects setuptools into sys.modules; which is mainly for compatibility with projects that use distutils.setup in their setup.py files.

With distutils being deprecated and slated for removal, we should drop our compatibility shim for this.

Describe the solution you’d like

Change the logic used for make_setuptools_shim_args, to not attempt the setuptools injection for Python 3.12+ (whenever distutils gets removed).

Alternative Solutions

Do nothing. Continue performing this injection after Python 3.12+, since it’ll be a no-op.

Additional context

https://pip.pypa.io/en/stable/cli/pip/#setuptools-injection for the current documentation on this.

Code of Conduct

• I agree to follow the PSF Code of Conduct.

[hugovk]

i.e. weit until 3.12beta1 or so

The 3.12 schedule isn’t published yet, but looking at the 3.11 schedule, I’d expect 3.12beta1 to be some time around May 2023.

[uranusjr]

Note that while distutils is scheduled for removal in 3.12, it is not guaranteed to be, and if we remove the shim without Python actually removing the module, the bare distutils.core.setup() call would do more harm than we keep the legacy path. So the removal should not happen before distutils is actually gone (i.e. weit until 3.12beta1 or so).