bpo-37258: Not a bug, but added a unit test and updated documentation. (GH-14229)
diff --git a/Lib/test/test_logging.py b/Lib/test/test_logging.py
index ac8919d..6507d79 100644
--- a/Lib/test/test_logging.py
+++ b/Lib/test/test_logging.py
@@ -4172,6 +4172,37 @@
logging.setLoggerClass(logging.Logger)
self.assertEqual(logging.getLoggerClass(), logging.Logger)
+ def test_subclass_logger_cache(self):
+ # bpo-37258
+ message = []
+
+ class MyLogger(logging.getLoggerClass()):
+ def __init__(self, name='MyLogger', level=logging.NOTSET):
+ super().__init__(name, level)
+ message.append('initialized')
+
+ logging.setLoggerClass(MyLogger)
+ logger = logging.getLogger('just_some_logger')
+ self.assertEqual(message, ['initialized'])
+ stream = io.StringIO()
+ h = logging.StreamHandler(stream)
+ logger.addHandler(h)
+ try:
+ logger.setLevel(logging.DEBUG)
+ logger.debug("hello")
+ self.assertEqual(stream.getvalue().strip(), "hello")
+
+ stream.truncate(0)
+ stream.seek(0)
+
+ logger.setLevel(logging.INFO)
+ logger.debug("hello")
+ self.assertEqual(stream.getvalue(), "")
+ finally:
+ logger.removeHandler(h)
+ h.close()
+ logging.setLoggerClass(logging.Logger)
+
@support.requires_type_collecting
def test_logging_at_shutdown(self):
# Issue #20037