[BUG] setuptools' distutils override no longer shows DeprecationWarning

setuptools version

setuptools==65.0.1

Python version

any

OS

any

Additional environment information

No response

Description

Recent versions of setuptools override Python stdlib's distutils with setuptools._distutils via _distutils_hack. This version does not contain code to issue deprecation warnings. It's a deviation from upstream code. setuptools should keep the deprecation warning to inform users that they should move from distutils to setuptools.

See also https://github.com/pypa/setuptools/issues/3532

Expected behavior

$ venv/bin/pip install "setuptools==59.6.0"
$ venv/bin/python -Werror -c "import distutils"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib64/python3.10/distutils/__init__.py", line 19, in <module>
    warnings.warn(_DEPRECATION_MESSAGE,
DeprecationWarning: The distutils package is deprecated and slated for removal in Python 3.12. Use setuptools or check PEP 632 for potential alternatives

How to Reproduce

1. python3 -m venv venv
2. Install recent setuptools, e,g. venv/bin/pip install "setuptools==65.0.1"
3. Run venv/bin/python -Werror -c "import distutils"

Output

no output, command does not raise a deprecation warning

Start by inspecting setuptools' _distutils_hack and compare its distutils override behavior with the Python standard-library warning shown in the issue. Reproduce the problem with python -Werror -c "import distutils" after installing setuptools 65.0.1. Done means the override emits the expected DeprecationWarning and the relevant behavior is covered by a regression test.