Issue #11870: Skip test_threading.test_2_join_in_forked_process() on platforms
with known OS bugs
Share the list of platforms with known OS bugs with other tests. Patch written
by Charles-François Natali.
diff --git a/Lib/test/test_threading.py b/Lib/test/test_threading.py
index 946c1d2..bdb7f14 100644
--- a/Lib/test/test_threading.py
+++ b/Lib/test/test_threading.py
@@ -417,6 +417,13 @@
class ThreadJoinOnShutdown(BaseTestCase):
+ # Between fork() and exec(), only async-safe functions are allowed (issues
+ # #12316 and #11870), and fork() from a worker thread is known to trigger
+ # problems with some operating systems (issue #3863): skip problematic tests
+ # on platforms known to behave badly.
+ platforms_to_skip = ('freebsd4', 'freebsd5', 'freebsd6', 'netbsd5',
+ 'os2emx')
+
def _run_and_join(self, script):
script = """if 1:
import sys, os, time, threading
@@ -448,11 +455,10 @@
self._run_and_join(script)
+ @unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
+ @unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
def test_2_join_in_forked_process(self):
# Like the test above, but from a forked interpreter
- import os
- if not hasattr(os, 'fork'):
- return
script = """if 1:
childpid = os.fork()
if childpid != 0:
@@ -466,19 +472,11 @@
"""
self._run_and_join(script)
+ @unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
+ @unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
def test_3_join_in_forked_from_thread(self):
# Like the test above, but fork() was called from a worker thread
# In the forked process, the main Thread object must be marked as stopped.
- import os
- if not hasattr(os, 'fork'):
- return
- # Skip platforms with known problems forking from a worker thread.
- # See http://bugs.python.org/issue3863.
- if sys.platform in ('freebsd4', 'freebsd5', 'freebsd6', 'netbsd5',
- 'os2emx'):
- print >>sys.stderr, ('Skipping test_3_join_in_forked_from_thread'
- ' due to known OS bugs on'), sys.platform
- return
script = """if 1:
main_thread = threading.current_thread()
def worker():
@@ -507,15 +505,11 @@
self.assertEqual(data, expected_output)
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
+ @unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
def test_4_joining_across_fork_in_worker_thread(self):
# There used to be a possible deadlock when forking from a child
# thread. See http://bugs.python.org/issue6643.
- # Skip platforms with known problems forking from a worker thread.
- # See http://bugs.python.org/issue3863.
- if sys.platform in ('freebsd4', 'freebsd5', 'freebsd6', 'os2emx'):
- raise unittest.SkipTest('due to known OS bugs on ' + sys.platform)
-
# The script takes the following steps:
# - The main thread in the parent process starts a new thread and then
# tries to join it.
@@ -584,6 +578,7 @@
self.assertScriptHasOutput(script, "end of main\n")
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
+ @unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
def test_5_clear_waiter_locks_to_avoid_crash(self):
# Check that a spawned thread that forks doesn't segfault on certain
# platforms, namely OS X. This used to happen if there was a waiter
@@ -596,10 +591,6 @@
# lock will be acquired, we can't know if the internal mutex will be
# acquired at the time of the fork.
- # Skip platforms with known problems forking from a worker thread.
- # See http://bugs.python.org/issue3863.
- if sys.platform in ('freebsd4', 'freebsd5', 'freebsd6', 'os2emx'):
- raise unittest.SkipTest('due to known OS bugs on ' + sys.platform)
script = """if True:
import os, time, threading