From db098bc1f05bd0773943e59f83489f05f28dedf8 Mon Sep 17 00:00:00 2001 From: idomic Date: Tue, 26 May 2020 10:54:21 -0400 Subject: bpo-39244: multiprocessing return default start method first on macOS (GH-18625) --- Lib/multiprocessing/context.py | 7 ++++--- Lib/test/_test_multiprocessing.py | 4 +++- Misc/NEWS.d/next/Library/2020-02-23-15-09-47.bpo-39244.aBK5IM.rst | 2 ++ 3 files changed, 9 insertions(+), 4 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2020-02-23-15-09-47.bpo-39244.aBK5IM.rst diff --git a/Lib/multiprocessing/context.py b/Lib/multiprocessing/context.py index 5f8e0f0..8d0525d 100644 --- a/Lib/multiprocessing/context.py +++ b/Lib/multiprocessing/context.py @@ -257,10 +257,11 @@ class DefaultContext(BaseContext): if sys.platform == 'win32': return ['spawn'] else: + methods = ['spawn', 'fork'] if sys.platform == 'darwin' else ['fork', 'spawn'] if reduction.HAVE_SEND_HANDLE: - return ['fork', 'spawn', 'forkserver'] - else: - return ['fork', 'spawn'] + methods.append('forkserver') + return methods + # # Context types for fixed start method diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py index dc8164f..155a827 100644 --- a/Lib/test/_test_multiprocessing.py +++ b/Lib/test/_test_multiprocessing.py @@ -5039,7 +5039,9 @@ class TestStartMethod(unittest.TestCase): self.assertEqual(methods, ['spawn']) else: self.assertTrue(methods == ['fork', 'spawn'] or - methods == ['fork', 'spawn', 'forkserver']) + methods == ['spawn', 'fork'] or + methods == ['fork', 'spawn', 'forkserver'] or + methods == ['spawn', 'fork', 'forkserver']) def test_preload_resources(self): if multiprocessing.get_start_method() != 'forkserver': diff --git a/Misc/NEWS.d/next/Library/2020-02-23-15-09-47.bpo-39244.aBK5IM.rst b/Misc/NEWS.d/next/Library/2020-02-23-15-09-47.bpo-39244.aBK5IM.rst new file mode 100644 index 0000000..c7d8e0d --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-02-23-15-09-47.bpo-39244.aBK5IM.rst @@ -0,0 +1,2 @@ +Fixed :class:`multiprocessing.context.get_all_start_methods` +to properly return the default method first on macOS. -- cgit v0.12