bpo-35424: test_multiprocessing: join 3 pools (GH-10986)

Join 3 pools in these tests:

* test.test_multiprocessing_spawn.WithProcessesTestPool.test_context
* test.test_multiprocessing_spawn.WithProcessesTestPool.test_traceback
(cherry picked from commit 388c8c208d9d09bd28289c1e4776b947d4d0f0f0)

Co-authored-by: Victor Stinner <vstinner@redhat.com>

diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py
index 6cafc2e9cbc0e24d7a2e961f369b8a12444c6fd8..d5c1ec1284828a55b4c99cdd7d1f792dfbc2b6c6 100644 (file)
--- a/Lib/test/_test_multiprocessing.py
+++ b/Lib/test/_test_multiprocessing.py
@@ -2199,6 +2199,7 @@ class _TestPool(BaseTestCase):
             with self.Pool(2) as p:
                 r = p.map_async(sqr, L)
                 self.assertEqual(r.get(), expected)
+            p.join()
             self.assertRaises(ValueError, p.map_async, sqr, L)
 
     @classmethod
@@ -2216,6 +2217,7 @@ class _TestPool(BaseTestCase):
                     exc = e
                 else:
                     self.fail('expected RuntimeError')
+            p.join()
             self.assertIs(type(exc), RuntimeError)
             self.assertEqual(exc.args, (123,))
             cause = exc.__cause__
@@ -2240,6 +2242,7 @@ class _TestPool(BaseTestCase):
                     self.fail('expected SayWhenError')
                 self.assertIs(type(exc), SayWhenError)
                 self.assertIs(exc.__cause__, None)
+            p.join()
 
     @classmethod
     def _test_wrapped_exception(cls):