test_array modifies `warnings.filter`

[vstinner]

$ ./python -m test test_array --fail-env-changed -m test.test_array.ArrayReconstructorTest.test_error
0:00:00 load avg: 17.75 Run tests sequentially
0:00:00 load avg: 17.75 [1/1] test_array
Warning -- warnings.filters was modified by test_array
Warning -- Before: (140159909806320, [], [])
Warning -- After: (140159909806320, [], [('ignore', re.compile("The 'u' type code is deprecated and will be removed in Python 3.16", re.IGNORECASE), <class 'DeprecationWarning'>, None, 0)]) 
test_array failed (env changed)

== Tests result: ENV CHANGED ==

1 test altered the execution environment:
 test_array

Total duration: 321 ms
Tests result: ENV CHANGED

cc @methane @hugovk

Linked PRs

• gh-106162: fix test_array modifies warning filter #106181
• gh-106162: array: suppress warning in test_array #106404

[hugovk]

I can't reproduce on macOS.

Does the filterwarnings in setUp not work?

cpython/Lib/test/test_array.py

Lines 102 to 107 in 1f74b9e

	def setUp(self):
	warnings.filterwarnings(
	"ignore",
	message="The 'u' type code is deprecated and "
	"will be removed in Python 3.16",
	category=DeprecationWarning)