Issue #14308: Fix an exception when a "dummy" thread is in the threading module's active list after a fork().
diff --git a/Lib/test/test_threading.py b/Lib/test/test_threading.py
index dfc0ddf..00f73a7 100644
--- a/Lib/test/test_threading.py
+++ b/Lib/test/test_threading.py
@@ -2,6 +2,8 @@
import test.support
from test.support import verbose, strip_python_stderr, import_module
+from test.script_helper import assert_python_ok
+
import random
import re
import sys
@@ -407,6 +409,33 @@
t.daemon = True
self.assertTrue('daemon' in repr(t))
+ @unittest.skipUnless(hasattr(os, 'fork'), 'test needs fork()')
+ def test_dummy_thread_after_fork(self):
+ # Issue #14308: a dummy thread in the active list doesn't mess up
+ # the after-fork mechanism.
+ code = """if 1:
+ import _thread, threading, os, time
+
+ def background_thread(evt):
+ # Creates and registers the _DummyThread instance
+ threading.current_thread()
+ evt.set()
+ time.sleep(10)
+
+ evt = threading.Event()
+ _thread.start_new_thread(background_thread, (evt,))
+ evt.wait()
+ assert threading.active_count() == 2, threading.active_count()
+ if os.fork() == 0:
+ assert threading.active_count() == 1, threading.active_count()
+ os._exit(0)
+ else:
+ os.wait()
+ """
+ _, out, err = assert_python_ok("-c", code)
+ self.assertEqual(out, b'')
+ self.assertEqual(err, b'')
+
class ThreadJoinOnShutdown(BaseTestCase):