Issue #10763: subprocess.communicate() closes stdout and stderr if both are

pipes (bug specific to Windows).

Improve also the unit test: write a portable unit test.
This commit is contained in:
Victor Stinner 2010-12-25 22:40:32 +00:00
parent 291151b7f4
commit 667d4b577f
3 changed files with 24 additions and 14 deletions

View file

@ -366,22 +366,28 @@ class ProcessTestCase(BaseTestCase):
self.assertEqual(stdout, b"banana")
self.assertStderrEqual(stderr, b"pineapple")
# This test is Linux specific for simplicity to at least have
# some coverage. It is not a platform specific bug.
@unittest.skipUnless(os.path.isdir('/proc/%d/fd' % os.getpid()),
"Linux specific")
# Test for the fd leak reported in http://bugs.python.org/issue2791.
def test_communicate_pipe_fd_leak(self):
fd_directory = '/proc/%d/fd' % os.getpid()
num_fds_before_popen = len(os.listdir(fd_directory))
p = subprocess.Popen([sys.executable, "-c", "print()"],
stdout=subprocess.PIPE)
p.communicate()
num_fds_after_communicate = len(os.listdir(fd_directory))
del p
num_fds_after_destruction = len(os.listdir(fd_directory))
self.assertEqual(num_fds_before_popen, num_fds_after_destruction)
self.assertEqual(num_fds_before_popen, num_fds_after_communicate)
for stdin_pipe in (False, True):
for stdout_pipe in (False, True):
for stderr_pipe in (False, True):
options = {}
if stdin_pipe:
options['stdin'] = subprocess.PIPE
if stdout_pipe:
options['stdout'] = subprocess.PIPE
if stderr_pipe:
options['stderr'] = subprocess.PIPE
if not options:
continue
p = subprocess.Popen((sys.executable, "-c", "pass"), **options)
p.communicate()
if p.stdin is not None:
self.assertTrue(p.stdin.closed)
if p.stdout is not None:
self.assertTrue(p.stdout.closed)
if p.stderr is not None:
self.assertTrue(p.stderr.closed)
def test_communicate_returns(self):
# communicate() should return None if no redirection is active