bpo-38762: Extend logging.test_multiprocessing to cover missing cases. (GH-22142)
diff --git a/Lib/test/test_logging.py b/Lib/test/test_logging.py
index 00a4825..d23fbfb 100644
--- a/Lib/test/test_logging.py
+++ b/Lib/test/test_logging.py
@@ -4354,15 +4354,65 @@
r.removeHandler(h)
h.close()
- def test_multiprocessing(self):
- r = logging.makeLogRecord({})
- self.assertEqual(r.processName, 'MainProcess')
+ @staticmethod # pickled as target of child process in the following test
+ def _extract_logrecord_process_name(key, logMultiprocessing, conn=None):
+ prev_logMultiprocessing = logging.logMultiprocessing
+ logging.logMultiprocessing = logMultiprocessing
try:
import multiprocessing as mp
+ name = mp.current_process().name
+
+ r1 = logging.makeLogRecord({'msg': f'msg1_{key}'})
+ del sys.modules['multiprocessing']
+ r2 = logging.makeLogRecord({'msg': f'msg2_{key}'})
+
+ results = {'processName' : name,
+ 'r1.processName': r1.processName,
+ 'r2.processName': r2.processName,
+ }
+ finally:
+ logging.logMultiprocessing = prev_logMultiprocessing
+ if conn:
+ conn.send(results)
+ else:
+ return results
+
+ def test_multiprocessing(self):
+ multiprocessing_imported = 'multiprocessing' in sys.modules
+ try:
+ # logMultiprocessing is True by default
+ self.assertEqual(logging.logMultiprocessing, True)
+
+ LOG_MULTI_PROCESSING = True
+ # When logMultiprocessing == True:
+ # In the main process processName = 'MainProcess'
r = logging.makeLogRecord({})
- self.assertEqual(r.processName, mp.current_process().name)
- except ImportError:
- pass
+ self.assertEqual(r.processName, 'MainProcess')
+
+ results = self._extract_logrecord_process_name(1, LOG_MULTI_PROCESSING)
+ self.assertEqual('MainProcess', results['processName'])
+ self.assertEqual('MainProcess', results['r1.processName'])
+ self.assertEqual('MainProcess', results['r2.processName'])
+
+ # In other processes, processName is correct when multiprocessing in imported,
+ # but it is (incorrectly) defaulted to 'MainProcess' otherwise (bpo-38762).
+ import multiprocessing
+ parent_conn, child_conn = multiprocessing.Pipe()
+ p = multiprocessing.Process(
+ target=self._extract_logrecord_process_name,
+ args=(2, LOG_MULTI_PROCESSING, child_conn,)
+ )
+ p.start()
+ results = parent_conn.recv()
+ self.assertNotEqual('MainProcess', results['processName'])
+ self.assertEqual(results['processName'], results['r1.processName'])
+ self.assertEqual('MainProcess', results['r2.processName'])
+ p.join()
+
+ finally:
+ if multiprocessing_imported:
+ import multiprocessing
+
def test_optional(self):
r = logging.makeLogRecord({})