gh-139322: Remove redundant test_os.Win32ErrorTests

[vstinner]

test_os OSErrorTests already covers the OSError class and is more complete than Win32ErrorTests.

• Issue: Tests: move test_posix.py and test_os.py into a new test_os package #139322

[vstinner]

cc @serhiy-storchaka

[serhiy-storchaka]

Maybe test for more concrete OSError subclass? It is FileExistsError on Linux.

Also, NotADirectoryError for os.path.join(filename, 'subdir') and FileNotFoundError for os.path.join(filename, 'subdir') if filename does not exist,

[vstinner]

Let me try with FileExistsError.

[serhiy-storchaka]

LGTM. 👍

But if we add a new test, I suggest to add also tests for os.path.join(filename, 'subdir'), before and after creation of filename. AFAIK, this is not tested.

[vstinner]

Merged. I added more tests on chdir() errors.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 CentOS9 NoGIL Refleaks 3.x (tier-1) has failed when building commit af01b46.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1610/builds/2155) and take a look at the build logs.
4. Check if the failure is related to this commit (af01b46) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1610/builds/2155

Failed tests:

• test_free_threading

Test leaking resources:

• test_free_threading: file descriptors

Summary of the results of the build (if available):

==

Click to see traceback logs

remote: Enumerating objects: 7, done. remote: Counting objects: 20% (1/5) remote: Counting objects: 40% (2/5) remote: Counting objects: 60% (3/5) remote: Counting objects: 80% (4/5) remote: Counting objects: 100% (5/5) remote: Counting objects: 100% (5/5), done. remote: Compressing objects: 50% (1/2) remote: Compressing objects: 100% (2/2) remote: Compressing objects: 100% (2/2), done. remote: Total 7 (delta 3), reused 3 (delta 3), pack-reused 2 (from 1) 
From https://github.com/python/cpython
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Turn off this advice by setting config variable advice.detachedHead to false
HEAD is now at af01b468661 gh-139322: Remove redundant `test_os.Win32ErrorTests` (#139477)
Switched to and reset branch 'main'
configure: WARNING: no system libmpdec found; falling back to pure-Python version for the decimal modulemake: *** [Makefile:2487: buildbottest] Error 2