bpo-44451: Reset DeprecationWarning filters in test_importlib.test_entry_points_by_index

[hroncok]

This avoids the following error if DeprecationWarnings are ignored.

======================================================================
ERROR: test_entry_points_by_index (test.test_importlib.test_metadata_api.APITests)
Prior versions of Distribution.entry_points would return a
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/builddir/build/BUILD/Python-3.10.0b3/Lib/test/test_importlib/test_metadata_api.py", line 145, in test_entry_points_by_index
    expected = next(iter(caught))
StopIteration
----------------------------------------------------------------------
Ran 1402 tests in 2.125s
FAILED (errors=1, skipped=18, expected failures=1)

https://bugs.python.org/issue44451

[hroncok]

Also in python/importlib_metadata#325

[vstinner]

LGTM.

cc @warsaw @jaraco: I'm not comfortable to merge this change, since there is the importlib_metadata package on PyPI and I don't how it's maintained and by who. Miro already created a backport PR! python/importlib_metadata#325

Without the PR, the test fails with -Wignore:

$ ./python -Wignore -m test test_importlib -m test_entry_points_by_index
...
test test_importlib failed -- Traceback (most recent call last):
  File "/home/vstinner/python/main/Lib/test/test_importlib/test_metadata_api.py", line 145, in test_entry_points_by_index
    expected = next(iter(caught))
StopIteration
Tests result: FAILURE

With the PR, the test pass as expected:

$ ./python -Wignore -m test test_importlib -m test_entry_points_by_index
...
Tests result: SUCCESS

[vstinner]

Azure Pipelines PR — #20210618.18 failed

test_httpservers failed on 32-bit and 64-bit Windows jobs, no idea why:

======================================================================
FAIL: test_accept (test.test_httpservers.CGIHTTPServerTestCase) [OrderedDict([('Accept', 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8')])]
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:\a\1\s\lib\test\test_httpservers.py", line 854, in test_accept
    self.assertIn(expected.encode('ascii'), res.read())
AssertionError: b"'HTTP_ACCEPT': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'" not found in b''

======================================================================
FAIL: test_accept (test.test_httpservers.CGIHTTPServerTestCase) [OrderedDict()]
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:\a\1\s\lib\test\test_httpservers.py", line 854, in test_accept
    self.assertIn(expected.encode('ascii'), res.read())
AssertionError: b"'HTTP_ACCEPT': ''" not found in b''

======================================================================
FAIL: test_accept (test.test_httpservers.CGIHTTPServerTestCase) [OrderedDict([('Accept', 'text/html'), ('ACCEPT', 'text/plain')])]
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:\a\1\s\lib\test\test_httpservers.py", line 854, in test_accept
    self.assertIn(expected.encode('ascii'), res.read())
AssertionError: b"'HTTP_ACCEPT': 'text/html,text/plain'" not found in b''

[jaraco]

test_httpservers failed on 32-bit and 64-bit Windows jobs, no idea why:

I'm all but certain this failure is spurious, unrelated, and thus ignorable.

Also in python/importlib_metadata#325

Thanks for that... although now I notice that the third-party module neither needs the behavior nor implements it for test_entry_points_dict_construction. Since it's seemingly only needed for CPython, I'm tempted to just merge the changes here (and the cpython branch of importlib_metadata).

Regardless, I'd like to make the approach consistent. I'll work on that in importlib_metadata. This change is good for CPython here and best to get it in asap.

[jaraco]

I don't see any way to re-run the failed tests, so I'm going to assume they're spurious and proceed.

[miss-islington]

Thanks @hroncok for the PR, and @jaraco for merging it 🌮🎉.. I'm working now to backport this PR to: 3.10.
🐍🍒⛏🤖 I'm not a witch! I'm not a witch!

[bedevere-bot]

GH-26790 is a backport of this pull request to the 3.10 branch.