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MinDalle_StableDiff/Python39/Lib/test/test_sys.py

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Added libs ti python
2022-09-17 15:26:13 +03:00
from test import support
from test.support.script_helper import assert_python_ok, assert_python_failure
import builtins
import codecs
import gc
import locale
import operator
import os
import struct
import subprocess
import sys
import sysconfig
import test.support
import textwrap
import unittest
import warnings
# count the number of test runs, used to create unique
# strings to intern in test_intern()
INTERN_NUMRUNS = 0
class DisplayHookTest(unittest.TestCase):
def test_original_displayhook(self):
dh = sys.__displayhook__
with support.captured_stdout() as out:
dh(42)
self.assertEqual(out.getvalue(), "42\n")
self.assertEqual(builtins._, 42)
del builtins._
with support.captured_stdout() as out:
dh(None)
self.assertEqual(out.getvalue(), "")
self.assertTrue(not hasattr(builtins, "_"))
# sys.displayhook() requires arguments
self.assertRaises(TypeError, dh)
stdout = sys.stdout
try:
del sys.stdout
self.assertRaises(RuntimeError, dh, 42)
finally:
sys.stdout = stdout
def test_lost_displayhook(self):
displayhook = sys.displayhook
try:
del sys.displayhook
code = compile("42", "<string>", "single")
self.assertRaises(RuntimeError, eval, code)
finally:
sys.displayhook = displayhook
def test_custom_displayhook(self):
def baddisplayhook(obj):
raise ValueError
with support.swap_attr(sys, 'displayhook', baddisplayhook):
code = compile("42", "<string>", "single")
self.assertRaises(ValueError, eval, code)
class ExceptHookTest(unittest.TestCase):
def test_original_excepthook(self):
try:
raise ValueError(42)
except ValueError as exc:
with support.captured_stderr() as err:
sys.__excepthook__(*sys.exc_info())
self.assertTrue(err.getvalue().endswith("ValueError: 42\n"))
self.assertRaises(TypeError, sys.__excepthook__)
def test_excepthook_bytes_filename(self):
# bpo-37467: sys.excepthook() must not crash if a filename
# is a bytes string
with warnings.catch_warnings():
warnings.simplefilter('ignore', BytesWarning)
try:
raise SyntaxError("msg", (b"bytes_filename", 123, 0, "text"))
except SyntaxError as exc:
with support.captured_stderr() as err:
sys.__excepthook__(*sys.exc_info())
err = err.getvalue()
self.assertIn(""" File "b'bytes_filename'", line 123\n""", err)
self.assertIn(""" text\n""", err)
self.assertTrue(err.endswith("SyntaxError: msg\n"))
def test_excepthook(self):
with test.support.captured_output("stderr") as stderr:
sys.excepthook(1, '1', 1)
self.assertTrue("TypeError: print_exception(): Exception expected for " \
"value, str found" in stderr.getvalue())
# FIXME: testing the code for a lost or replaced excepthook in
# Python/pythonrun.c::PyErr_PrintEx() is tricky.
class SysModuleTest(unittest.TestCase):
def tearDown(self):
test.support.reap_children()
def test_exit(self):
# call with two arguments
self.assertRaises(TypeError, sys.exit, 42, 42)
# call without argument
with self.assertRaises(SystemExit) as cm:
sys.exit()
self.assertIsNone(cm.exception.code)
rc, out, err = assert_python_ok('-c', 'import sys; sys.exit()')
self.assertEqual(rc, 0)
self.assertEqual(out, b'')
self.assertEqual(err, b'')
# call with integer argument
with self.assertRaises(SystemExit) as cm:
sys.exit(42)
self.assertEqual(cm.exception.code, 42)
# call with tuple argument with one entry
# entry will be unpacked
with self.assertRaises(SystemExit) as cm:
sys.exit((42,))
self.assertEqual(cm.exception.code, 42)
# call with string argument
with self.assertRaises(SystemExit) as cm:
sys.exit("exit")
self.assertEqual(cm.exception.code, "exit")
# call with tuple argument with two entries
with self.assertRaises(SystemExit) as cm:
sys.exit((17, 23))
self.assertEqual(cm.exception.code, (17, 23))
# test that the exit machinery handles SystemExits properly
rc, out, err = assert_python_failure('-c', 'raise SystemExit(47)')
self.assertEqual(rc, 47)
self.assertEqual(out, b'')
self.assertEqual(err, b'')
def check_exit_message(code, expected, **env_vars):
rc, out, err = assert_python_failure('-c', code, **env_vars)
self.assertEqual(rc, 1)
self.assertEqual(out, b'')
self.assertTrue(err.startswith(expected),
"%s doesn't start with %s" % (ascii(err), ascii(expected)))
# test that stderr buffer is flushed before the exit message is written
# into stderr
check_exit_message(
r'import sys; sys.stderr.write("unflushed,"); sys.exit("message")',
b"unflushed,message")
# test that the exit message is written with backslashreplace error
# handler to stderr
check_exit_message(
r'import sys; sys.exit("surrogates:\uDCFF")',
b"surrogates:\\udcff")
# test that the unicode message is encoded to the stderr encoding
# instead of the default encoding (utf8)
check_exit_message(
r'import sys; sys.exit("h\xe9")',
b"h\xe9", PYTHONIOENCODING='latin-1')
def test_getdefaultencoding(self):
self.assertRaises(TypeError, sys.getdefaultencoding, 42)
# can't check more than the type, as the user might have changed it
self.assertIsInstance(sys.getdefaultencoding(), str)
# testing sys.settrace() is done in test_sys_settrace.py
# testing sys.setprofile() is done in test_sys_setprofile.py
def test_switchinterval(self):
self.assertRaises(TypeError, sys.setswitchinterval)
self.assertRaises(TypeError, sys.setswitchinterval, "a")
self.assertRaises(ValueError, sys.setswitchinterval, -1.0)
self.assertRaises(ValueError, sys.setswitchinterval, 0.0)
orig = sys.getswitchinterval()
# sanity check
self.assertTrue(orig < 0.5, orig)
try:
for n in 0.00001, 0.05, 3.0, orig:
sys.setswitchinterval(n)
self.assertAlmostEqual(sys.getswitchinterval(), n)
finally:
sys.setswitchinterval(orig)
def test_recursionlimit(self):
self.assertRaises(TypeError, sys.getrecursionlimit, 42)
oldlimit = sys.getrecursionlimit()
self.assertRaises(TypeError, sys.setrecursionlimit)
self.assertRaises(ValueError, sys.setrecursionlimit, -42)
sys.setrecursionlimit(10000)
self.assertEqual(sys.getrecursionlimit(), 10000)
sys.setrecursionlimit(oldlimit)
def test_recursionlimit_recovery(self):
if hasattr(sys, 'gettrace') and sys.gettrace():
self.skipTest('fatal error if run with a trace function')
oldlimit = sys.getrecursionlimit()
def f():
f()
try:
for depth in (10, 25, 50, 75, 100, 250, 1000):
try:
sys.setrecursionlimit(depth)
except RecursionError:
# Issue #25274: The recursion limit is too low at the
# current recursion depth
continue
# Issue #5392: test stack overflow after hitting recursion
# limit twice
self.assertRaises(RecursionError, f)
self.assertRaises(RecursionError, f)
finally:
sys.setrecursionlimit(oldlimit)
@test.support.cpython_only
def test_setrecursionlimit_recursion_depth(self):
# Issue #25274: Setting a low recursion limit must be blocked if the
# current recursion depth is already higher than the "lower-water
# mark". Otherwise, it may not be possible anymore to
# reset the overflowed flag to 0.
from _testinternalcapi import get_recursion_depth
def set_recursion_limit_at_depth(depth, limit):
recursion_depth = get_recursion_depth()
if recursion_depth >= depth:
with self.assertRaises(RecursionError) as cm:
sys.setrecursionlimit(limit)
self.assertRegex(str(cm.exception),
"cannot set the recursion limit to [0-9]+ "
"at the recursion depth [0-9]+: "
"the limit is too low")
else:
set_recursion_limit_at_depth(depth, limit)
oldlimit = sys.getrecursionlimit()
try:
sys.setrecursionlimit(1000)
for limit in (10, 25, 50, 75, 100, 150, 200):
# formula extracted from _Py_RecursionLimitLowerWaterMark()
if limit > 200:
depth = limit - 50
else:
depth = limit * 3 // 4
set_recursion_limit_at_depth(depth, limit)
finally:
sys.setrecursionlimit(oldlimit)
# The error message is specific to CPython
@test.support.cpython_only
def test_recursionlimit_fatalerror(self):
# A fatal error occurs if a second recursion limit is hit when recovering
# from a first one.
code = textwrap.dedent("""
import sys
def f():
try:
f()
except RecursionError:
f()
sys.setrecursionlimit(%d)
f()""")
with test.support.SuppressCrashReport():
for i in (50, 1000):
sub = subprocess.Popen([sys.executable, '-c', code % i],
stderr=subprocess.PIPE)
err = sub.communicate()[1]
self.assertTrue(sub.returncode, sub.returncode)
self.assertIn(
b"Fatal Python error: _Py_CheckRecursiveCall: "
b"Cannot recover from stack overflow",
err)
def test_getwindowsversion(self):
# Raise SkipTest if sys doesn't have getwindowsversion attribute
test.support.get_attribute(sys, "getwindowsversion")
v = sys.getwindowsversion()
self.assertEqual(len(v), 5)
self.assertIsInstance(v[0], int)
self.assertIsInstance(v[1], int)
self.assertIsInstance(v[2], int)
self.assertIsInstance(v[3], int)
self.assertIsInstance(v[4], str)
self.assertRaises(IndexError, operator.getitem, v, 5)
self.assertIsInstance(v.major, int)
self.assertIsInstance(v.minor, int)
self.assertIsInstance(v.build, int)
self.assertIsInstance(v.platform, int)
self.assertIsInstance(v.service_pack, str)
self.assertIsInstance(v.service_pack_minor, int)
self.assertIsInstance(v.service_pack_major, int)
self.assertIsInstance(v.suite_mask, int)
self.assertIsInstance(v.product_type, int)
self.assertEqual(v[0], v.major)
self.assertEqual(v[1], v.minor)
self.assertEqual(v[2], v.build)
self.assertEqual(v[3], v.platform)
self.assertEqual(v[4], v.service_pack)
# This is how platform.py calls it. Make sure tuple
# still has 5 elements
maj, min, buildno, plat, csd = sys.getwindowsversion()
def test_call_tracing(self):
self.assertRaises(TypeError, sys.call_tracing, type, 2)
@unittest.skipUnless(hasattr(sys, "setdlopenflags"),
'test needs sys.setdlopenflags()')
def test_dlopenflags(self):
self.assertTrue(hasattr(sys, "getdlopenflags"))
self.assertRaises(TypeError, sys.getdlopenflags, 42)
oldflags = sys.getdlopenflags()
self.assertRaises(TypeError, sys.setdlopenflags)
sys.setdlopenflags(oldflags+1)
self.assertEqual(sys.getdlopenflags(), oldflags+1)
sys.setdlopenflags(oldflags)
@test.support.refcount_test
def test_refcount(self):
# n here must be a global in order for this test to pass while
# tracing with a python function. Tracing calls PyFrame_FastToLocals
# which will add a copy of any locals to the frame object, causing
# the reference count to increase by 2 instead of 1.
global n
self.assertRaises(TypeError, sys.getrefcount)
c = sys.getrefcount(None)
n = None
self.assertEqual(sys.getrefcount(None), c+1)
del n
self.assertEqual(sys.getrefcount(None), c)
if hasattr(sys, "gettotalrefcount"):
self.assertIsInstance(sys.gettotalrefcount(), int)
def test_getframe(self):
self.assertRaises(TypeError, sys._getframe, 42, 42)
self.assertRaises(ValueError, sys._getframe, 2000000000)
self.assertTrue(
SysModuleTest.test_getframe.__code__ \
is sys._getframe().f_code
)
# sys._current_frames() is a CPython-only gimmick.
@test.support.reap_threads
def test_current_frames(self):
import threading
import traceback
# Spawn a thread that blocks at a known place. Then the main
# thread does sys._current_frames(), and verifies that the frames
# returned make sense.
entered_g = threading.Event()
leave_g = threading.Event()
thread_info = [] # the thread's id
def f123():
g456()
def g456():
thread_info.append(threading.get_ident())
entered_g.set()
leave_g.wait()
t = threading.Thread(target=f123)
t.start()
entered_g.wait()
# At this point, t has finished its entered_g.set(), although it's
# impossible to guess whether it's still on that line or has moved on
# to its leave_g.wait().
self.assertEqual(len(thread_info), 1)
thread_id = thread_info[0]
d = sys._current_frames()
for tid in d:
self.assertIsInstance(tid, int)
self.assertGreater(tid, 0)
main_id = threading.get_ident()
self.assertIn(main_id, d)
self.assertIn(thread_id, d)
# Verify that the captured main-thread frame is _this_ frame.
frame = d.pop(main_id)
self.assertTrue(frame is sys._getframe())
# Verify that the captured thread frame is blocked in g456, called
# from f123. This is a litte tricky, since various bits of
# threading.py are also in the thread's call stack.
frame = d.pop(thread_id)
stack = traceback.extract_stack(frame)
for i, (filename, lineno, funcname, sourceline) in enumerate(stack):
if funcname == "f123":
break
else:
self.fail("didn't find f123() on thread's call stack")
self.assertEqual(sourceline, "g456()")
# And the next record must be for g456().
filename, lineno, funcname, sourceline = stack[i+1]
self.assertEqual(funcname, "g456")
self.assertIn(sourceline, ["leave_g.wait()", "entered_g.set()"])
# Reap the spawned thread.
leave_g.set()
t.join()
def test_attributes(self):
self.assertIsInstance(sys.api_version, int)
self.assertIsInstance(sys.argv, list)
self.assertIn(sys.byteorder, ("little", "big"))
self.assertIsInstance(sys.builtin_module_names, tuple)
self.assertIsInstance(sys.copyright, str)
self.assertIsInstance(sys.exec_prefix, str)
self.assertIsInstance(sys.base_exec_prefix, str)
self.assertIsInstance(sys.executable, str)
self.assertEqual(len(sys.float_info), 11)
self.assertEqual(sys.float_info.radix, 2)
self.assertEqual(len(sys.int_info), 2)
self.assertTrue(sys.int_info.bits_per_digit % 5 == 0)
self.assertTrue(sys.int_info.sizeof_digit >= 1)
self.assertEqual(type(sys.int_info.bits_per_digit), int)
self.assertEqual(type(sys.int_info.sizeof_digit), int)
self.assertIsInstance(sys.hexversion, int)
self.assertEqual(len(sys.hash_info), 9)
self.assertLess(sys.hash_info.modulus, 2**sys.hash_info.width)
# sys.hash_info.modulus should be a prime; we do a quick
# probable primality test (doesn't exclude the possibility of
# a Carmichael number)
for x in range(1, 100):
self.assertEqual(
pow(x, sys.hash_info.modulus-1, sys.hash_info.modulus),
1,
"sys.hash_info.modulus {} is a non-prime".format(
sys.hash_info.modulus)
)
self.assertIsInstance(sys.hash_info.inf, int)
self.assertIsInstance(sys.hash_info.nan, int)
self.assertIsInstance(sys.hash_info.imag, int)
algo = sysconfig.get_config_var("Py_HASH_ALGORITHM")
if sys.hash_info.algorithm in {"fnv", "siphash24"}:
self.assertIn(sys.hash_info.hash_bits, {32, 64})
self.assertIn(sys.hash_info.seed_bits, {32, 64, 128})
if algo == 1:
self.assertEqual(sys.hash_info.algorithm, "siphash24")
elif algo == 2:
self.assertEqual(sys.hash_info.algorithm, "fnv")
else:
self.assertIn(sys.hash_info.algorithm, {"fnv", "siphash24"})
else:
# PY_HASH_EXTERNAL
self.assertEqual(algo, 0)
self.assertGreaterEqual(sys.hash_info.cutoff, 0)
self.assertLess(sys.hash_info.cutoff, 8)
self.assertIsInstance(sys.maxsize, int)
self.assertIsInstance(sys.maxunicode, int)
self.assertEqual(sys.maxunicode, 0x10FFFF)
self.assertIsInstance(sys.platform, str)
self.assertIsInstance(sys.prefix, str)
self.assertIsInstance(sys.base_prefix, str)
self.assertIsInstance(sys.platlibdir, str)
self.assertIsInstance(sys.version, str)
vi = sys.version_info
self.assertIsInstance(vi[:], tuple)
self.assertEqual(len(vi), 5)
self.assertIsInstance(vi[0], int)
self.assertIsInstance(vi[1], int)
self.assertIsInstance(vi[2], int)
self.assertIn(vi[3], ("alpha", "beta", "candidate", "final"))
self.assertIsInstance(vi[4], int)
self.assertIsInstance(vi.major, int)
self.assertIsInstance(vi.minor, int)
self.assertIsInstance(vi.micro, int)
self.assertIn(vi.releaselevel, ("alpha", "beta", "candidate", "final"))
self.assertIsInstance(vi.serial, int)
self.assertEqual(vi[0], vi.major)
self.assertEqual(vi[1], vi.minor)
self.assertEqual(vi[2], vi.micro)
self.assertEqual(vi[3], vi.releaselevel)
self.assertEqual(vi[4], vi.serial)
self.assertTrue(vi > (1,0,0))
self.assertIsInstance(sys.float_repr_style, str)
self.assertIn(sys.float_repr_style, ('short', 'legacy'))
if not sys.platform.startswith('win'):
self.assertIsInstance(sys.abiflags, str)
def test_thread_info(self):
info = sys.thread_info
self.assertEqual(len(info), 3)
self.assertIn(info.name, ('nt', 'pthread', 'solaris', None))
self.assertIn(info.lock, ('semaphore', 'mutex+cond', None))
def test_43581(self):
# Can't use sys.stdout, as this is a StringIO object when
# the test runs under regrtest.
self.assertEqual(sys.__stdout__.encoding, sys.__stderr__.encoding)
def test_intern(self):
global INTERN_NUMRUNS
INTERN_NUMRUNS += 1
self.assertRaises(TypeError, sys.intern)
s = "never interned before" + str(INTERN_NUMRUNS)
self.assertTrue(sys.intern(s) is s)
s2 = s.swapcase().swapcase()
self.assertTrue(sys.intern(s2) is s)
# Subclasses of string can't be interned, because they
# provide too much opportunity for insane things to happen.
# We don't want them in the interned dict and if they aren't
# actually interned, we don't want to create the appearance
# that they are by allowing intern() to succeed.
class S(str):
def __hash__(self):
return 123
self.assertRaises(TypeError, sys.intern, S("abc"))
def test_sys_flags(self):
self.assertTrue(sys.flags)
attrs = ("debug",
"inspect", "interactive", "optimize",
"dont_write_bytecode", "no_user_site", "no_site",
"ignore_environment", "verbose", "bytes_warning", "quiet",
"hash_randomization", "isolated", "dev_mode", "utf8_mode")
for attr in attrs:
self.assertTrue(hasattr(sys.flags, attr), attr)
attr_type = bool if attr == "dev_mode" else int
self.assertEqual(type(getattr(sys.flags, attr)), attr_type, attr)
self.assertTrue(repr(sys.flags))
self.assertEqual(len(sys.flags), len(attrs))
self.assertIn(sys.flags.utf8_mode, {0, 1, 2})
def assert_raise_on_new_sys_type(self, sys_attr):
# Users are intentionally prevented from creating new instances of
# sys.flags, sys.version_info, and sys.getwindowsversion.
attr_type = type(sys_attr)
with self.assertRaises(TypeError):
attr_type()
with self.assertRaises(TypeError):
attr_type.__new__(attr_type)
def test_sys_flags_no_instantiation(self):
self.assert_raise_on_new_sys_type(sys.flags)
def test_sys_version_info_no_instantiation(self):
self.assert_raise_on_new_sys_type(sys.version_info)
def test_sys_getwindowsversion_no_instantiation(self):
# Skip if not being run on Windows.
test.support.get_attribute(sys, "getwindowsversion")
self.assert_raise_on_new_sys_type(sys.getwindowsversion())
@test.support.cpython_only
def test_clear_type_cache(self):
sys._clear_type_cache()
def test_ioencoding(self):
env = dict(os.environ)
# Test character: cent sign, encoded as 0x4A (ASCII J) in CP424,
# not representable in ASCII.
env["PYTHONIOENCODING"] = "cp424"
p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
stdout = subprocess.PIPE, env=env)
out = p.communicate()[0].strip()
expected = ("\xa2" + os.linesep).encode("cp424")
self.assertEqual(out, expected)
env["PYTHONIOENCODING"] = "ascii:replace"
p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
stdout = subprocess.PIPE, env=env)
out = p.communicate()[0].strip()
self.assertEqual(out, b'?')
env["PYTHONIOENCODING"] = "ascii"
p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
env=env)
out, err = p.communicate()
self.assertEqual(out, b'')
self.assertIn(b'UnicodeEncodeError:', err)
self.assertIn(rb"'\xa2'", err)
env["PYTHONIOENCODING"] = "ascii:"
p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
env=env)
out, err = p.communicate()
self.assertEqual(out, b'')
self.assertIn(b'UnicodeEncodeError:', err)
self.assertIn(rb"'\xa2'", err)
env["PYTHONIOENCODING"] = ":surrogateescape"
p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xdcbd))'],
stdout=subprocess.PIPE, env=env)
out = p.communicate()[0].strip()
self.assertEqual(out, b'\xbd')
@unittest.skipUnless(test.support.FS_NONASCII,
'requires OS support of non-ASCII encodings')
@unittest.skipUnless(sys.getfilesystemencoding() == locale.getpreferredencoding(False),
'requires FS encoding to match locale')
def test_ioencoding_nonascii(self):
env = dict(os.environ)
env["PYTHONIOENCODING"] = ""
p = subprocess.Popen([sys.executable, "-c",
'print(%a)' % test.support.FS_NONASCII],
stdout=subprocess.PIPE, env=env)
out = p.communicate()[0].strip()
self.assertEqual(out, os.fsencode(test.support.FS_NONASCII))
@unittest.skipIf(sys.base_prefix != sys.prefix,
'Test is not venv-compatible')
def test_executable(self):
# sys.executable should be absolute
self.assertEqual(os.path.abspath(sys.executable), sys.executable)
# Issue #7774: Ensure that sys.executable is an empty string if argv[0]
# has been set to a non existent program name and Python is unable to
# retrieve the real program name
# For a normal installation, it should work without 'cwd'
# argument. For test runs in the build directory, see #7774.
python_dir = os.path.dirname(os.path.realpath(sys.executable))
p = subprocess.Popen(
["nonexistent", "-c",
'import sys; print(sys.executable.encode("ascii", "backslashreplace"))'],
executable=sys.executable, stdout=subprocess.PIPE, cwd=python_dir)
stdout = p.communicate()[0]
executable = stdout.strip().decode("ASCII")
p.wait()
self.assertIn(executable, ["b''", repr(sys.executable.encode("ascii", "backslashreplace"))])
def check_fsencoding(self, fs_encoding, expected=None):
self.assertIsNotNone(fs_encoding)
codecs.lookup(fs_encoding)
if expected:
self.assertEqual(fs_encoding, expected)
def test_getfilesystemencoding(self):
fs_encoding = sys.getfilesystemencoding()
if sys.platform == 'darwin':
expected = 'utf-8'
else:
expected = None
self.check_fsencoding(fs_encoding, expected)
def c_locale_get_error_handler(self, locale, isolated=False, encoding=None):
# Force the POSIX locale
env = os.environ.copy()
env["LC_ALL"] = locale
env["PYTHONCOERCECLOCALE"] = "0"
code = '\n'.join((
'import sys',
'def dump(name):',
' std = getattr(sys, name)',
' print("%s: %s" % (name, std.errors))',
'dump("stdin")',
'dump("stdout")',
'dump("stderr")',
))
args = [sys.executable, "-X", "utf8=0", "-c", code]
if isolated:
args.append("-I")
if encoding is not None:
env['PYTHONIOENCODING'] = encoding
else:
env.pop('PYTHONIOENCODING', None)
p = subprocess.Popen(args,
stdout=subprocess.PIPE,
stderr=subprocess.STDOUT,
env=env,
universal_newlines=True)
stdout, stderr = p.communicate()
return stdout
def check_locale_surrogateescape(self, locale):
out = self.c_locale_get_error_handler(locale, isolated=True)
self.assertEqual(out,
'stdin: surrogateescape\n'
'stdout: surrogateescape\n'
'stderr: backslashreplace\n')
# replace the default error handler
out = self.c_locale_get_error_handler(locale, encoding=':ignore')
self.assertEqual(out,
'stdin: ignore\n'
'stdout: ignore\n'
'stderr: backslashreplace\n')
# force the encoding
out = self.c_locale_get_error_handler(locale, encoding='iso8859-1')
self.assertEqual(out,
'stdin: strict\n'
'stdout: strict\n'
'stderr: backslashreplace\n')
out = self.c_locale_get_error_handler(locale, encoding='iso8859-1:')
self.assertEqual(out,
'stdin: strict\n'
'stdout: strict\n'
'stderr: backslashreplace\n')
# have no any effect
out = self.c_locale_get_error_handler(locale, encoding=':')
self.assertEqual(out,
'stdin: surrogateescape\n'
'stdout: surrogateescape\n'
'stderr: backslashreplace\n')
out = self.c_locale_get_error_handler(locale, encoding='')
self.assertEqual(out,
'stdin: surrogateescape\n'
'stdout: surrogateescape\n'
'stderr: backslashreplace\n')
def test_c_locale_surrogateescape(self):
self.check_locale_surrogateescape('C')
def test_posix_locale_surrogateescape(self):
self.check_locale_surrogateescape('POSIX')
def test_implementation(self):
# This test applies to all implementations equally.
levels = {'alpha': 0xA, 'beta': 0xB, 'candidate': 0xC, 'final': 0xF}
self.assertTrue(hasattr(sys.implementation, 'name'))
self.assertTrue(hasattr(sys.implementation, 'version'))
self.assertTrue(hasattr(sys.implementation, 'hexversion'))
self.assertTrue(hasattr(sys.implementation, 'cache_tag'))
version = sys.implementation.version
self.assertEqual(version[:2], (version.major, version.minor))
hexversion = (version.major << 24 | version.minor << 16 |
version.micro << 8 | levels[version.releaselevel] << 4 |
version.serial << 0)
self.assertEqual(sys.implementation.hexversion, hexversion)
# PEP 421 requires that .name be lower case.
self.assertEqual(sys.implementation.name,
sys.implementation.name.lower())
@test.support.cpython_only
def test_debugmallocstats(self):
# Test sys._debugmallocstats()
from test.support.script_helper import assert_python_ok
args = ['-c', 'import sys; sys._debugmallocstats()']
ret, out, err = assert_python_ok(*args)
self.assertIn(b"free PyDictObjects", err)
# The function has no parameter
self.assertRaises(TypeError, sys._debugmallocstats, True)
@unittest.skipUnless(hasattr(sys, "getallocatedblocks"),
"sys.getallocatedblocks unavailable on this build")
def test_getallocatedblocks(self):
try:
import _testcapi
except ImportError:
with_pymalloc = support.with_pymalloc()
else:
try:
alloc_name = _testcapi.pymem_getallocatorsname()
except RuntimeError as exc:
# "cannot get allocators name" (ex: tracemalloc is used)
with_pymalloc = True
else:
with_pymalloc = (alloc_name in ('pymalloc', 'pymalloc_debug'))
# Some sanity checks
a = sys.getallocatedblocks()
self.assertIs(type(a), int)
if with_pymalloc:
self.assertGreater(a, 0)
else:
# When WITH_PYMALLOC isn't available, we don't know anything
# about the underlying implementation: the function might
# return 0 or something greater.
self.assertGreaterEqual(a, 0)
try:
# While we could imagine a Python session where the number of
# multiple buffer objects would exceed the sharing of references,
# it is unlikely to happen in a normal test run.
self.assertLess(a, sys.gettotalrefcount())
except AttributeError:
# gettotalrefcount() not available
pass
gc.collect()
b = sys.getallocatedblocks()
self.assertLessEqual(b, a)
gc.collect()
c = sys.getallocatedblocks()
self.assertIn(c, range(b - 50, b + 50))
def test_is_finalizing(self):
self.assertIs(sys.is_finalizing(), False)
# Don't use the atexit module because _Py_Finalizing is only set
# after calling atexit callbacks
code = """if 1:
import sys
class AtExit:
is_finalizing = sys.is_finalizing
print = print
def __del__(self):
self.print(self.is_finalizing(), flush=True)
# Keep a reference in the __main__ module namespace, so the
# AtExit destructor will be called at Python exit
ref = AtExit()
"""
rc, stdout, stderr = assert_python_ok('-c', code)
self.assertEqual(stdout.rstrip(), b'True')
def test_issue20602(self):
# sys.flags and sys.float_info were wiped during shutdown.
code = """if 1:
import sys
class A:
def __del__(self, sys=sys):
print(sys.flags)
print(sys.float_info)
a = A()
"""
rc, out, err = assert_python_ok('-c', code)
out = out.splitlines()
self.assertIn(b'sys.flags', out[0])
self.assertIn(b'sys.float_info', out[1])
def test_sys_ignores_cleaning_up_user_data(self):
code = """if 1:
import struct, sys
class C:
def __init__(self):
self.pack = struct.pack
def __del__(self):
self.pack('I', -42)
sys.x = C()
"""
rc, stdout, stderr = assert_python_ok('-c', code)
self.assertEqual(rc, 0)
self.assertEqual(stdout.rstrip(), b"")
self.assertEqual(stderr.rstrip(), b"")
@unittest.skipUnless(hasattr(sys, 'getandroidapilevel'),
'need sys.getandroidapilevel()')
def test_getandroidapilevel(self):
level = sys.getandroidapilevel()
self.assertIsInstance(level, int)
self.assertGreater(level, 0)
def test_sys_tracebacklimit(self):
code = """if 1:
import sys
def f1():
1 / 0
def f2():
f1()
sys.tracebacklimit = %r
f2()
"""
def check(tracebacklimit, expected):
p = subprocess.Popen([sys.executable, '-c', code % tracebacklimit],
stderr=subprocess.PIPE)
out = p.communicate()[1]
self.assertEqual(out.splitlines(), expected)
traceback = [
b'Traceback (most recent call last):',
b' File "<string>", line 8, in <module>',
b' File "<string>", line 6, in f2',
b' File "<string>", line 4, in f1',
b'ZeroDivisionError: division by zero'
]
check(10, traceback)
check(3, traceback)
check(2, traceback[:1] + traceback[2:])
check(1, traceback[:1] + traceback[3:])
check(0, [traceback[-1]])
check(-1, [traceback[-1]])
check(1<<1000, traceback)
check(-1<<1000, [traceback[-1]])
check(None, traceback)
def test_no_duplicates_in_meta_path(self):
self.assertEqual(len(sys.meta_path), len(set(sys.meta_path)))
@unittest.skipUnless(hasattr(sys, "_enablelegacywindowsfsencoding"),
'needs sys._enablelegacywindowsfsencoding()')
def test__enablelegacywindowsfsencoding(self):
code = ('import sys',
'sys._enablelegacywindowsfsencoding()',
'print(sys.getfilesystemencoding(), sys.getfilesystemencodeerrors())')
rc, out, err = assert_python_ok('-c', '; '.join(code))
out = out.decode('ascii', 'replace').rstrip()
self.assertEqual(out, 'mbcs replace')
@test.support.cpython_only
class UnraisableHookTest(unittest.TestCase):
def write_unraisable_exc(self, exc, err_msg, obj):
import _testcapi
import types
err_msg2 = f"Exception ignored {err_msg}"
try:
_testcapi.write_unraisable_exc(exc, err_msg, obj)
return types.SimpleNamespace(exc_type=type(exc),
exc_value=exc,
exc_traceback=exc.__traceback__,
err_msg=err_msg2,
object=obj)
finally:
# Explicitly break any reference cycle
exc = None
def test_original_unraisablehook(self):
for err_msg in (None, "original hook"):
with self.subTest(err_msg=err_msg):
obj = "an object"
with test.support.captured_output("stderr") as stderr:
with test.support.swap_attr(sys, 'unraisablehook',
sys.__unraisablehook__):
self.write_unraisable_exc(ValueError(42), err_msg, obj)
err = stderr.getvalue()
if err_msg is not None:
self.assertIn(f'Exception ignored {err_msg}: {obj!r}\n', err)
else:
self.assertIn(f'Exception ignored in: {obj!r}\n', err)
self.assertIn('Traceback (most recent call last):\n', err)
self.assertIn('ValueError: 42\n', err)
def test_original_unraisablehook_err(self):
# bpo-22836: PyErr_WriteUnraisable() should give sensible reports
class BrokenDel:
def __del__(self):
exc = ValueError("del is broken")
# The following line is included in the traceback report:
raise exc
class BrokenStrException(Exception):
def __str__(self):
raise Exception("str() is broken")
class BrokenExceptionDel:
def __del__(self):
exc = BrokenStrException()
# The following line is included in the traceback report:
raise exc
for test_class in (BrokenDel, BrokenExceptionDel):
with self.subTest(test_class):
obj = test_class()
with test.support.captured_stderr() as stderr, \
test.support.swap_attr(sys, 'unraisablehook',
sys.__unraisablehook__):
# Trigger obj.__del__()
del obj
report = stderr.getvalue()
self.assertIn("Exception ignored", report)
self.assertIn(test_class.__del__.__qualname__, report)
self.assertIn("test_sys.py", report)
self.assertIn("raise exc", report)
if test_class is BrokenExceptionDel:
self.assertIn("BrokenStrException", report)
self.assertIn("<exception str() failed>", report)
else:
self.assertIn("ValueError", report)
self.assertIn("del is broken", report)
self.assertTrue(report.endswith("\n"))
def test_original_unraisablehook_wrong_type(self):
exc = ValueError(42)
with test.support.swap_attr(sys, 'unraisablehook',
sys.__unraisablehook__):
with self.assertRaises(TypeError):
sys.unraisablehook(exc)
def test_custom_unraisablehook(self):
hook_args = None
def hook_func(args):
nonlocal hook_args
hook_args = args
obj = object()
try:
with test.support.swap_attr(sys, 'unraisablehook', hook_func):
expected = self.write_unraisable_exc(ValueError(42),
"custom hook", obj)
for attr in "exc_type exc_value exc_traceback err_msg object".split():
self.assertEqual(getattr(hook_args, attr),
getattr(expected, attr),
(hook_args, expected))
finally:
# expected and hook_args contain an exception: break reference cycle
expected = None
hook_args = None
def test_custom_unraisablehook_fail(self):
def hook_func(*args):
raise Exception("hook_func failed")
with test.support.captured_output("stderr") as stderr:
with test.support.swap_attr(sys, 'unraisablehook', hook_func):
self.write_unraisable_exc(ValueError(42),
"custom hook fail", None)
err = stderr.getvalue()
self.assertIn(f'Exception ignored in sys.unraisablehook: '
f'{hook_func!r}\n',
err)
self.assertIn('Traceback (most recent call last):\n', err)
self.assertIn('Exception: hook_func failed\n', err)
@test.support.cpython_only
class SizeofTest(unittest.TestCase):
def setUp(self):
self.P = struct.calcsize('P')
self.longdigit = sys.int_info.sizeof_digit
import _testinternalcapi
self.gc_headsize = _testinternalcapi.SIZEOF_PYGC_HEAD
check_sizeof = test.support.check_sizeof
def test_gc_head_size(self):
# Check that the gc header size is added to objects tracked by the gc.
vsize = test.support.calcvobjsize
gc_header_size = self.gc_headsize
# bool objects are not gc tracked
self.assertEqual(sys.getsizeof(True), vsize('') + self.longdigit)
# but lists are
self.assertEqual(sys.getsizeof([]), vsize('Pn') + gc_header_size)
def test_errors(self):
class BadSizeof:
def __sizeof__(self):
raise ValueError
self.assertRaises(ValueError, sys.getsizeof, BadSizeof())
class InvalidSizeof:
def __sizeof__(self):
return None
self.assertRaises(TypeError, sys.getsizeof, InvalidSizeof())
sentinel = ["sentinel"]
self.assertIs(sys.getsizeof(InvalidSizeof(), sentinel), sentinel)
class FloatSizeof:
def __sizeof__(self):
return 4.5
self.assertRaises(TypeError, sys.getsizeof, FloatSizeof())
self.assertIs(sys.getsizeof(FloatSizeof(), sentinel), sentinel)
class OverflowSizeof(int):
def __sizeof__(self):
return int(self)
self.assertEqual(sys.getsizeof(OverflowSizeof(sys.maxsize)),
sys.maxsize + self.gc_headsize)
with self.assertRaises(OverflowError):
sys.getsizeof(OverflowSizeof(sys.maxsize + 1))
with self.assertRaises(ValueError):
sys.getsizeof(OverflowSizeof(-1))
with self.assertRaises((ValueError, OverflowError)):
sys.getsizeof(OverflowSizeof(-sys.maxsize - 1))
def test_default(self):
size = test.support.calcvobjsize
self.assertEqual(sys.getsizeof(True), size('') + self.longdigit)
self.assertEqual(sys.getsizeof(True, -1), size('') + self.longdigit)
def test_objecttypes(self):
# check all types defined in Objects/
calcsize = struct.calcsize
size = test.support.calcobjsize
vsize = test.support.calcvobjsize
check = self.check_sizeof
# bool
check(True, vsize('') + self.longdigit)
# buffer
# XXX
# builtin_function_or_method
check(len, size('5P'))
# bytearray
samples = [b'', b'u'*100000]
for sample in samples:
x = bytearray(sample)
check(x, vsize('n2Pi') + x.__alloc__())
# bytearray_iterator
check(iter(bytearray()), size('nP'))
# bytes
check(b'', vsize('n') + 1)
check(b'x' * 10, vsize('n') + 11)
# cell
def get_cell():
x = 42
def inner():
return x
return inner
check(get_cell().__closure__[0], size('P'))
# code
def check_code_size(a, expected_size):
self.assertGreaterEqual(sys.getsizeof(a), expected_size)
check_code_size(get_cell().__code__, size('6i13P'))
check_code_size(get_cell.__code__, size('6i13P'))
def get_cell2(x):
def inner():
return x
return inner
check_code_size(get_cell2.__code__, size('6i13P') + calcsize('n'))
# complex
check(complex(0,1), size('2d'))
# method_descriptor (descriptor object)
check(str.lower, size('3PPP'))
# classmethod_descriptor (descriptor object)
# XXX
# member_descriptor (descriptor object)
import datetime
check(datetime.timedelta.days, size('3PP'))
# getset_descriptor (descriptor object)
import collections
check(collections.defaultdict.default_factory, size('3PP'))
# wrapper_descriptor (descriptor object)
check(int.__add__, size('3P2P'))
# method-wrapper (descriptor object)
check({}.__iter__, size('2P'))
# empty dict
check({}, size('nQ2P'))
# dict
check({"a": 1}, size('nQ2P') + calcsize('2nP2n') + 8 + (8*2//3)*calcsize('n2P'))
longdict = {1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8}
check(longdict, size('nQ2P') + calcsize('2nP2n') + 16 + (16*2//3)*calcsize('n2P'))
# dictionary-keyview
check({}.keys(), size('P'))
# dictionary-valueview
check({}.values(), size('P'))
# dictionary-itemview
check({}.items(), size('P'))
# dictionary iterator
check(iter({}), size('P2nPn'))
# dictionary-keyiterator
check(iter({}.keys()), size('P2nPn'))
# dictionary-valueiterator
check(iter({}.values()), size('P2nPn'))
# dictionary-itemiterator
check(iter({}.items()), size('P2nPn'))
# dictproxy
class C(object): pass
check(C.__dict__, size('P'))
# BaseException
check(BaseException(), size('5Pb'))
# UnicodeEncodeError
check(UnicodeEncodeError("", "", 0, 0, ""), size('5Pb 2P2nP'))
# UnicodeDecodeError
check(UnicodeDecodeError("", b"", 0, 0, ""), size('5Pb 2P2nP'))
# UnicodeTranslateError
check(UnicodeTranslateError("", 0, 1, ""), size('5Pb 2P2nP'))
# ellipses
check(Ellipsis, size(''))
# EncodingMap
import codecs, encodings.iso8859_3
x = codecs.charmap_build(encodings.iso8859_3.decoding_table)
check(x, size('32B2iB'))
# enumerate
check(enumerate([]), size('n3P'))
# reverse
check(reversed(''), size('nP'))
# float
check(float(0), size('d'))
# sys.floatinfo
check(sys.float_info, vsize('') + self.P * len(sys.float_info))
# frame
import inspect
CO_MAXBLOCKS = 20
x = inspect.currentframe()
ncells = len(x.f_code.co_cellvars)
nfrees = len(x.f_code.co_freevars)
extras = x.f_code.co_stacksize + x.f_code.co_nlocals +\
ncells + nfrees - 1
check(x, vsize('5P2c4P3ic' + CO_MAXBLOCKS*'3i' + 'P' + extras*'P'))
# function
def func(): pass
check(func, size('13P'))
class c():
@staticmethod
def foo():
pass
@classmethod
def bar(cls):
pass
# staticmethod
check(foo, size('PP'))
# classmethod
check(bar, size('PP'))
# generator
def get_gen(): yield 1
check(get_gen(), size('Pb2PPP4P'))
# iterator
check(iter('abc'), size('lP'))
# callable-iterator
import re
check(re.finditer('',''), size('2P'))
# list
samples = [[], [1,2,3], ['1', '2', '3']]
for sample in samples:
check(list(sample), vsize('Pn') + len(sample)*self.P)
# sortwrapper (list)
# XXX
# cmpwrapper (list)
# XXX
# listiterator (list)
check(iter([]), size('lP'))
# listreverseiterator (list)
check(reversed([]), size('nP'))
# int
check(0, vsize(''))
check(1, vsize('') + self.longdigit)
check(-1, vsize('') + self.longdigit)
PyLong_BASE = 2**sys.int_info.bits_per_digit
check(int(PyLong_BASE), vsize('') + 2*self.longdigit)
check(int(PyLong_BASE**2-1), vsize('') + 2*self.longdigit)
check(int(PyLong_BASE**2), vsize('') + 3*self.longdigit)
# module
check(unittest, size('PnPPP'))
# None
check(None, size(''))
# NotImplementedType
check(NotImplemented, size(''))
# object
check(object(), size(''))
# property (descriptor object)
class C(object):
def getx(self): return self.__x
def setx(self, value): self.__x = value
def delx(self): del self.__x
x = property(getx, setx, delx, "")
check(x, size('4Pi'))
# PyCapsule
# XXX
# rangeiterator
check(iter(range(1)), size('4l'))
# reverse
check(reversed(''), size('nP'))
# range
check(range(1), size('4P'))
check(range(66000), size('4P'))
# set
# frozenset
PySet_MINSIZE = 8
samples = [[], range(10), range(50)]
s = size('3nP' + PySet_MINSIZE*'nP' + '2nP')
for sample in samples:
minused = len(sample)
if minused == 0: tmp = 1
# the computation of minused is actually a bit more complicated
# but this suffices for the sizeof test
minused = minused*2
newsize = PySet_MINSIZE
while newsize <= minused:
newsize = newsize << 1
if newsize <= 8:
check(set(sample), s)
check(frozenset(sample), s)
else:
check(set(sample), s + newsize*calcsize('nP'))
check(frozenset(sample), s + newsize*calcsize('nP'))
# setiterator
check(iter(set()), size('P3n'))
# slice
check(slice(0), size('3P'))
# super
check(super(int), size('3P'))
# tuple
check((), vsize(''))
check((1,2,3), vsize('') + 3*self.P)
# type
# static type: PyTypeObject
fmt = 'P2nPI13Pl4Pn9Pn11PIPP'
s = vsize(fmt)
check(int, s)
# class
s = vsize(fmt + # PyTypeObject
'3P' # PyAsyncMethods
'36P' # PyNumberMethods
'3P' # PyMappingMethods
'10P' # PySequenceMethods
'2P' # PyBufferProcs
'5P')
class newstyleclass(object): pass
# Separate block for PyDictKeysObject with 8 keys and 5 entries
check(newstyleclass, s + calcsize("2nP2n0P") + 8 + 5*calcsize("n2P"))
# dict with shared keys
check(newstyleclass().__dict__, size('nQ2P') + 5*self.P)
o = newstyleclass()
o.a = o.b = o.c = o.d = o.e = o.f = o.g = o.h = 1
# Separate block for PyDictKeysObject with 16 keys and 10 entries
check(newstyleclass, s + calcsize("2nP2n0P") + 16 + 10*calcsize("n2P"))
# dict with shared keys
check(newstyleclass().__dict__, size('nQ2P') + 10*self.P)
# unicode
# each tuple contains a string and its expected character size
# don't put any static strings here, as they may contain
# wchar_t or UTF-8 representations
samples = ['1'*100, '\xff'*50,
'\u0100'*40, '\uffff'*100,
'\U00010000'*30, '\U0010ffff'*100]
asciifields = "nnbP"
compactfields = asciifields + "nPn"
unicodefields = compactfields + "P"
for s in samples:
maxchar = ord(max(s))
if maxchar < 128:
L = size(asciifields) + len(s) + 1
elif maxchar < 256:
L = size(compactfields) + len(s) + 1
elif maxchar < 65536:
L = size(compactfields) + 2*(len(s) + 1)
else:
L = size(compactfields) + 4*(len(s) + 1)
check(s, L)
# verify that the UTF-8 size is accounted for
s = chr(0x4000) # 4 bytes canonical representation
check(s, size(compactfields) + 4)
# compile() will trigger the generation of the UTF-8
# representation as a side effect
compile(s, "<stdin>", "eval")
check(s, size(compactfields) + 4 + 4)
# TODO: add check that forces the presence of wchar_t representation
# TODO: add check that forces layout of unicodefields
# weakref
import weakref
check(weakref.ref(int), size('2Pn2P'))
# weakproxy
# XXX
# weakcallableproxy
check(weakref.proxy(int), size('2Pn2P'))
def check_slots(self, obj, base, extra):
expected = sys.getsizeof(base) + struct.calcsize(extra)
if gc.is_tracked(obj) and not gc.is_tracked(base):
expected += self.gc_headsize
self.assertEqual(sys.getsizeof(obj), expected)
def test_slots(self):
# check all subclassable types defined in Objects/ that allow
# non-empty __slots__
check = self.check_slots
class BA(bytearray):
__slots__ = 'a', 'b', 'c'
check(BA(), bytearray(), '3P')
class D(dict):
__slots__ = 'a', 'b', 'c'
check(D(x=[]), {'x': []}, '3P')
class L(list):
__slots__ = 'a', 'b', 'c'
check(L(), [], '3P')
class S(set):
__slots__ = 'a', 'b', 'c'
check(S(), set(), '3P')
class FS(frozenset):
__slots__ = 'a', 'b', 'c'
check(FS(), frozenset(), '3P')
from collections import OrderedDict
class OD(OrderedDict):
__slots__ = 'a', 'b', 'c'
check(OD(x=[]), OrderedDict(x=[]), '3P')
def test_pythontypes(self):
# check all types defined in Python/
size = test.support.calcobjsize
vsize = test.support.calcvobjsize
check = self.check_sizeof
# _ast.AST
import _ast
check(_ast.AST(), size('P'))
try:
raise TypeError
except TypeError:
tb = sys.exc_info()[2]
# traceback
if tb is not None:
check(tb, size('2P2i'))
# symtable entry
# XXX
# sys.flags
check(sys.flags, vsize('') + self.P * len(sys.flags))
def test_asyncgen_hooks(self):
old = sys.get_asyncgen_hooks()
self.assertIsNone(old.firstiter)
self.assertIsNone(old.finalizer)
firstiter = lambda *a: None
sys.set_asyncgen_hooks(firstiter=firstiter)
hooks = sys.get_asyncgen_hooks()
self.assertIs(hooks.firstiter, firstiter)
self.assertIs(hooks[0], firstiter)
self.assertIs(hooks.finalizer, None)
self.assertIs(hooks[1], None)
finalizer = lambda *a: None
sys.set_asyncgen_hooks(finalizer=finalizer)
hooks = sys.get_asyncgen_hooks()
self.assertIs(hooks.firstiter, firstiter)
self.assertIs(hooks[0], firstiter)
self.assertIs(hooks.finalizer, finalizer)
self.assertIs(hooks[1], finalizer)
sys.set_asyncgen_hooks(*old)
cur = sys.get_asyncgen_hooks()
self.assertIsNone(cur.firstiter)
self.assertIsNone(cur.finalizer)
def test_changing_sys_stderr_and_removing_reference(self):
# If the default displayhook doesn't take a strong reference
# to sys.stderr the following code can crash. See bpo-43660
# for more details.
code = textwrap.dedent('''
import sys
class MyStderr:
def write(self, s):
sys.stderr = None
sys.stderr = MyStderr()
1/0
''')
rc, out, err = assert_python_failure('-c', code)
self.assertEqual(out, b"")
self.assertEqual(err, b"")
if __name__ == "__main__":
unittest.main()