bpo-29620: iterate over a copy of sys.modules (GH-4800)

unittest.TestCase.assertWarns no longer raises a RuntimeException
when accessing a module's ``__warningregistry__`` causes importation of a new
module, or when a new module is imported in another thread. 

Patch by Kernc.
This commit is contained in:
kernc 2020-06-11 20:03:29 +02:00 committed by GitHub
parent 436b648910
commit 46398fba4d
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 19 additions and 1 deletions

View file

@ -252,7 +252,7 @@ class _AssertWarnsContext(_AssertRaisesBaseContext):
def __enter__(self):
# The __warningregistry__'s need to be in a pristine state for tests
# to work properly.
for v in sys.modules.values():
for v in list(sys.modules.values()):
if getattr(v, '__warningregistry__', None):
v.__warningregistry__ = {}
self.warnings_manager = warnings.catch_warnings(record=True)