gh-91265: Make old ctypes.macholib tests runned by python -m test

[arhadthedev]

Some tests for ctypes.macholib.dyld and all tests for ctypes.macholib.dylib and ctypes.macholib.framework are located outside of expected ctypes.test module and were not ported from assert to unittest facilities. This causes the following problems:

• the tests aren't run by python -m test so they are effectively dead
• an end user can run them by python -m ctypes.macholib.dyld, python -m ctypes.macholib.dylib, and python -m ctypes.macholib.framework
• they are available even if a user chose to install CPython without tests

This PR moves these tests into ctypes.test.test_macholib suit and wraps them as unittest.TestCase.

I believe this PR should be backported to not export unintended features in unintended places.

Fixes GH-91265.

[MaxwellDupre]

After rebuild against this PR: tests:
cpython on  pr/32094 via 🐍 v3.11.0a6+
✦ ❯ ./python -m unittest -vvv Lib/ctypes/test/test_macholib.py
Ran 3 tests in 0.000s
OK (skipped=3)

Or
./python -m test -vvv test_macholib
0:00:00 load avg: 1.07 Run tests sequentially
0:00:00 load avg: 1.07 [1/1] test_macholib
test test_macholib crashed -- Traceback (most recent call last):
File "/home/me/Documents/cpython/Lib/test/libregrtest/runtest.py", line 352, in _runtest_inner
refleak = _runtest_inner2(ns, test_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/me/Documents/cpython/Lib/test/libregrtest/runtest.py", line 292, in _runtest_inner2
the_module = importlib.import_module(abstest)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/me/Documents/cpython/Lib/importlib/init.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "", line 1206, in _gcd_import
File "", line 1178, in _find_and_load
File "", line 1142, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'test.test_macholib'

[arhadthedev]

Ping.

This PR doesn't add extra logic, it just collects stuff into Lib/ctypes/test/test_macholib.py and replaces assert with self.assertEqual/self.assertIsNone.

[ronaldoussoren]

I finally had some time to seriously look at this. The PR looks good to me, as the description says this moves some tests to explicit test files to ensure they are picked up by the regular test runs.

[ronaldoussoren]

@arhadthedev : Sorry about the delay in reviewing, I had to find some time to seriously look at this and be sure that tests are correctly moved.

Did you sign the CLA? The CLA check is blocking the merge of your PR.

[arhadthedev]

Sorry about the delay in reviewing

No worries! The issue needed the chance to collect feedback anyway.

Did you sign the CLA? The CLA check is blocking the merge of your PR.

Yes, both on the bpo (https://bugs.python.org/user40922) and after the migration (#91453 (comment), I'm one of authors there). So it's just a matter of waiting for the bot to be sorted out.

---

P. S.: @ronaldoussoren (because I know that the "Mentioned" queue is an order of magnitude less that the "Participating" one).

[arhadthedev]

@ronaldoussoren I've reopened the PR to retrigger the bot; it worked.