test_logging: test_config_queue_handler() race condition #93761
Description
The implementation of test_logging.test_config_queue_handler() uses time.sleep(0.010) as synchronization primitive.
@vsajip: please don't use time.sleep() as sync primitive: https://pythondev.readthedocs.io/unstable_tests.html#don-t-use-sleep-as-synchronization
The test fails when the machine is busy:
$ ./python -m test test_logging -m test_config_queue_handler -F -j10 -v
(...)
0:00:10 load avg: 2.36 [ 48/1] test_logging failed (1 failure)
test_config_queue_handler (test.test_logging.ConfigDictTest.test_config_queue_handler) ... FAIL
======================================================================
FAIL: test_config_queue_handler (test.test_logging.ConfigDictTest.test_config_queue_handler)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/vstinner/python/main/Lib/test/test_logging.py", line 3647, in test_config_queue_handler
self.do_queuehandler_configuration(qspec, lspec)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/vstinner/python/main/Lib/test/test_logging.py", line 3621, in do_queuehandler_configuration
self.assertEqual(data, ['foo', 'bar', 'baz'])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: Lists differ: [] != ['foo', 'bar', 'baz']
Second list contains 3 additional elements.
First extra element 0:
'foo'
- []
+ ['foo', 'bar', 'baz']
----------------------------------------------------------------------
Ran 1 test in 0.466s
FAILED (failures=1)
Extract of the test:
delay = 0.01
try:
self.apply_config(cd)
qh = logging.getHandlerByName('ah')
self.assertEqual(sorted(logging.getHandlerNames()), ['ah', 'h1'])
self.assertIsNotNone(qh.listener)
qh.listener.start()
# Need to let the listener thread get started
time.sleep(delay)
logging.debug('foo')
logging.info('bar')
logging.warning('baz')
# Need to let the listener thread finish its work
time.sleep(delay)
with open(fn, encoding='utf-8') as f:
data = f.read().splitlines()
self.assertEqual(data, ['foo', 'bar', 'baz'])
finally:
if qh:
qh.listener.stop()
h = logging.getHandlerByName('h1')
if h:
self.addCleanup(closeFileHandler, h, fn)
else:
self.addCleanup(os.remove, fn)