summaryrefslogtreecommitdiffstats
path: root/Lib/test/_test_multiprocessing.py
diff options
context:
space:
mode:
authorJake Tesler <jake.tesler@gmail.com>2019-11-19 19:50:12 (GMT)
committerMiss Islington (bot) <31488909+miss-islington@users.noreply.github.com>2019-11-19 19:50:12 (GMT)
commitc6b20be85c0de6f2355c67ae6e7e578941275cc0 (patch)
tree1482aa6693e3fa4001a0a77c8fd50fb1a0223f66 /Lib/test/_test_multiprocessing.py
parent892221bfa04a41cf581f988ba19dc263f557e157 (diff)
downloadcpython-c6b20be85c0de6f2355c67ae6e7e578941275cc0.zip
cpython-c6b20be85c0de6f2355c67ae6e7e578941275cc0.tar.gz
cpython-c6b20be85c0de6f2355c67ae6e7e578941275cc0.tar.bz2
bpo-38707: Fix for multiprocessing.Process MainThread.native_id (GH-17088)
This PR implements a fix for `multiprocessing.Process` objects; the error occurs when Processes are created using either `fork` or `forkserver` as the `start_method`. In these instances, the `MainThread` of the newly created `Process` object retains all attributes from its parent's `MainThread` object, including the `native_id` attribute. The resulting behavior is such that the new process' `MainThread` captures an incorrect/outdated `native_id` (the parent's instead of its own). This change forces the Process object to update its `native_id` attribute during the bootstrap process. cc @vstinner https://bugs.python.org/issue38707 Automerge-Triggered-By: @pitrou
Diffstat (limited to 'Lib/test/_test_multiprocessing.py')
-rw-r--r--Lib/test/_test_multiprocessing.py22
1 files changed, 22 insertions, 0 deletions
diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py
index f7bebc6..611291c 100644
--- a/Lib/test/_test_multiprocessing.py
+++ b/Lib/test/_test_multiprocessing.py
@@ -361,6 +361,28 @@ class _TestProcess(BaseTestCase):
self.assertNotIn(p, self.active_children())
close_queue(q)
+ @unittest.skipUnless(threading._HAVE_THREAD_NATIVE_ID, "needs native_id")
+ def test_process_mainthread_native_id(self):
+ if self.TYPE == 'threads':
+ self.skipTest('test not appropriate for {}'.format(self.TYPE))
+
+ current_mainthread_native_id = threading.main_thread().native_id
+
+ q = self.Queue(1)
+ p = self.Process(target=self._test_process_mainthread_native_id, args=(q,))
+ p.start()
+
+ child_mainthread_native_id = q.get()
+ p.join()
+ close_queue(q)
+
+ self.assertNotEqual(current_mainthread_native_id, child_mainthread_native_id)
+
+ @classmethod
+ def _test_process_mainthread_native_id(cls, q):
+ mainthread_native_id = threading.main_thread().native_id
+ q.put(mainthread_native_id)
+
@classmethod
def _sleep_some(cls):
time.sleep(100)