cpython/Lib/test/test_select.py

101 lines
3.3 KiB
Python

import errno
import os
import select
import subprocess
import sys
import textwrap
import unittest
from test import support
@unittest.skipIf((sys.platform[:3]=='win'),
"can't easily test on this system")
class SelectTestCase(unittest.TestCase):
class Nope:
pass
class Almost:
def fileno(self):
return 'fileno'
def test_error_conditions(self):
self.assertRaises(TypeError, select.select, 1, 2, 3)
self.assertRaises(TypeError, select.select, [self.Nope()], [], [])
self.assertRaises(TypeError, select.select, [self.Almost()], [], [])
self.assertRaises(TypeError, select.select, [], [], [], "not a number")
self.assertRaises(ValueError, select.select, [], [], [], -1)
# Issue #12367: http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/155606
@unittest.skipIf(sys.platform.startswith('freebsd'),
'skip because of a FreeBSD bug: kern/155606')
def test_errno(self):
with open(__file__, 'rb') as fp:
fd = fp.fileno()
fp.close()
try:
select.select([fd], [], [], 0)
except OSError as err:
self.assertEqual(err.errno, errno.EBADF)
else:
self.fail("exception not raised")
def test_returned_list_identity(self):
# See issue #8329
r, w, x = select.select([], [], [], 1)
self.assertIsNot(r, w)
self.assertIsNot(r, x)
self.assertIsNot(w, x)
@unittest.skipUnless(hasattr(os, 'popen'), "need os.popen()")
def test_select(self):
code = textwrap.dedent('''
import time
for i in range(10):
print("testing...", flush=True)
time.sleep(0.050)
''')
cmd = [sys.executable, '-I', '-c', code]
with subprocess.Popen(cmd, stdout=subprocess.PIPE) as proc:
pipe = proc.stdout
for timeout in (0, 1, 2, 4, 8, 16) + (None,)*10:
if support.verbose:
print(f'timeout = {timeout}')
rfd, wfd, xfd = select.select([pipe], [], [], timeout)
self.assertEqual(wfd, [])
self.assertEqual(xfd, [])
if not rfd:
continue
if rfd == [pipe]:
line = pipe.readline()
if support.verbose:
print(repr(line))
if not line:
if support.verbose:
print('EOF')
break
continue
self.fail('Unexpected return values from select():',
rfd, wfd, xfd)
# Issue 16230: Crash on select resized list
def test_select_mutated(self):
a = []
class F:
def fileno(self):
del a[-1]
return sys.__stdout__.fileno()
a[:] = [F()] * 10
self.assertEqual(select.select([], a, []), ([], a[:5], []))
def test_disallow_instantiation(self):
support.check_disallow_instantiation(self, type(select.poll()))
if hasattr(select, 'devpoll'):
support.check_disallow_instantiation(self, type(select.devpoll()))
def tearDownModule():
support.reap_children()
if __name__ == "__main__":
unittest.main()