diff --git a/Lib/multiprocessing/spawn.py b/Lib/multiprocessing/spawn.py index 1f4f3f496f5..693f2fb9d47 100644 --- a/Lib/multiprocessing/spawn.py +++ b/Lib/multiprocessing/spawn.py @@ -29,12 +29,19 @@ __all__ = ['_main', 'freeze_support', 'set_executable', 'get_executable', if sys.platform != 'win32': WINEXE = False WINSERVICE = False + _WINENV = False else: - WINEXE = (sys.platform == 'win32' and getattr(sys, 'frozen', False)) + WINEXE = getattr(sys, 'frozen', False) WINSERVICE = sys.executable.lower().endswith("pythonservice.exe") + _WINENV = '__PYVENV_LAUNCHER__' in os.environ if WINSERVICE: _python_exe = os.path.join(sys.exec_prefix, 'python.exe') +elif _WINENV: + # bpo-35797: When running in a venv, we need to bypass the redirect + # executor and launch our base Python. + import _winapi + _python_exe = _winapi.GetModuleFileName(0) else: _python_exe = sys.executable diff --git a/Lib/test/test_venv.py b/Lib/test/test_venv.py index 22a3b78852f..34c2234493b 100644 --- a/Lib/test/test_venv.py +++ b/Lib/test/test_venv.py @@ -306,6 +306,19 @@ class BasicTest(BaseTest): ) self.assertEqual(out.strip(), '0') + def test_multiprocessing(self): + """ + Test that the multiprocessing is able to spawn. + """ + rmtree(self.env_dir) + self.run_with_capture(venv.create, self.env_dir) + envpy = os.path.join(os.path.realpath(self.env_dir), + self.bindir, self.exe) + out, err = check_output([envpy, '-c', + 'from multiprocessing import Pool; ' + + 'print(Pool(1).apply_async("Python".lower).get(3))']) + self.assertEqual(out.strip(), "python".encode()) + @skipInVenv class EnsurePipTest(BaseTest): """Test venv module installation of pip.""" diff --git a/Misc/NEWS.d/next/Windows/2019-01-25-12-29-14.bpo-35797.MzyOK9.rst b/Misc/NEWS.d/next/Windows/2019-01-25-12-29-14.bpo-35797.MzyOK9.rst new file mode 100644 index 00000000000..a0745f500b1 --- /dev/null +++ b/Misc/NEWS.d/next/Windows/2019-01-25-12-29-14.bpo-35797.MzyOK9.rst @@ -0,0 +1 @@ +Fix default executable used by the multiprocessing module