cpython/Lib/test/test_cmd_line_script.py

672 lines
29 KiB
Python

# tests command line execution of scripts
import contextlib
import importlib
import importlib.machinery
import zipimport
import unittest
import sys
import os
import os.path
import py_compile
import subprocess
import io
import textwrap
from test import support
from test.support.script_helper import (
make_pkg, make_script, make_zip_pkg, make_zip_script,
assert_python_ok, assert_python_failure, spawn_python, kill_python)
verbose = support.verbose
example_args = ['test1', 'test2', 'test3']
test_source = """\
# Script may be run with optimisation enabled, so don't rely on assert
# statements being executed
def assertEqual(lhs, rhs):
if lhs != rhs:
raise AssertionError('%r != %r' % (lhs, rhs))
def assertIdentical(lhs, rhs):
if lhs is not rhs:
raise AssertionError('%r is not %r' % (lhs, rhs))
# Check basic code execution
result = ['Top level assignment']
def f():
result.append('Lower level reference')
f()
assertEqual(result, ['Top level assignment', 'Lower level reference'])
# Check population of magic variables
assertEqual(__name__, '__main__')
from importlib.machinery import BuiltinImporter
_loader = __loader__ if __loader__ is BuiltinImporter else type(__loader__)
print('__loader__==%a' % _loader)
print('__file__==%a' % __file__)
print('__cached__==%a' % __cached__)
print('__package__==%r' % __package__)
# Check PEP 451 details
import os.path
if __package__ is not None:
print('__main__ was located through the import system')
assertIdentical(__spec__.loader, __loader__)
expected_spec_name = os.path.splitext(os.path.basename(__file__))[0]
if __package__:
expected_spec_name = __package__ + "." + expected_spec_name
assertEqual(__spec__.name, expected_spec_name)
assertEqual(__spec__.parent, __package__)
assertIdentical(__spec__.submodule_search_locations, None)
assertEqual(__spec__.origin, __file__)
if __spec__.cached is not None:
assertEqual(__spec__.cached, __cached__)
# Check the sys module
import sys
assertIdentical(globals(), sys.modules[__name__].__dict__)
if __spec__ is not None:
# XXX: We're not currently making __main__ available under its real name
pass # assertIdentical(globals(), sys.modules[__spec__.name].__dict__)
from test import test_cmd_line_script
example_args_list = test_cmd_line_script.example_args
assertEqual(sys.argv[1:], example_args_list)
print('sys.argv[0]==%a' % sys.argv[0])
print('sys.path[0]==%a' % sys.path[0])
# Check the working directory
import os
print('cwd==%a' % os.getcwd())
"""
def _make_test_script(script_dir, script_basename, source=test_source):
to_return = make_script(script_dir, script_basename, source)
importlib.invalidate_caches()
return to_return
def _make_test_zip_pkg(zip_dir, zip_basename, pkg_name, script_basename,
source=test_source, depth=1):
to_return = make_zip_pkg(zip_dir, zip_basename, pkg_name, script_basename,
source, depth)
importlib.invalidate_caches()
return to_return
class CmdLineTest(unittest.TestCase):
def _check_output(self, script_name, exit_code, data,
expected_file, expected_argv0,
expected_path0, expected_package,
expected_loader, expected_cwd=None):
if verbose > 1:
print("Output from test script %r:" % script_name)
print(repr(data))
self.assertEqual(exit_code, 0)
printed_loader = '__loader__==%a' % expected_loader
printed_file = '__file__==%a' % expected_file
printed_package = '__package__==%r' % expected_package
printed_argv0 = 'sys.argv[0]==%a' % expected_argv0
printed_path0 = 'sys.path[0]==%a' % expected_path0
if expected_cwd is None:
expected_cwd = os.getcwd()
printed_cwd = 'cwd==%a' % expected_cwd
if verbose > 1:
print('Expected output:')
print(printed_file)
print(printed_package)
print(printed_argv0)
print(printed_cwd)
self.assertIn(printed_loader.encode('utf-8'), data)
self.assertIn(printed_file.encode('utf-8'), data)
self.assertIn(printed_package.encode('utf-8'), data)
self.assertIn(printed_argv0.encode('utf-8'), data)
self.assertIn(printed_path0.encode('utf-8'), data)
self.assertIn(printed_cwd.encode('utf-8'), data)
def _check_script(self, script_exec_args, expected_file,
expected_argv0, expected_path0,
expected_package, expected_loader,
*cmd_line_switches, cwd=None, **env_vars):
if isinstance(script_exec_args, str):
script_exec_args = [script_exec_args]
run_args = [*support.optim_args_from_interpreter_flags(),
*cmd_line_switches, *script_exec_args, *example_args]
rc, out, err = assert_python_ok(
*run_args, __isolated=False, __cwd=cwd, **env_vars
)
self._check_output(script_exec_args, rc, out + err, expected_file,
expected_argv0, expected_path0,
expected_package, expected_loader, cwd)
def _check_import_error(self, script_exec_args, expected_msg,
*cmd_line_switches, cwd=None, **env_vars):
if isinstance(script_exec_args, str):
script_exec_args = (script_exec_args,)
else:
script_exec_args = tuple(script_exec_args)
run_args = cmd_line_switches + script_exec_args
rc, out, err = assert_python_failure(
*run_args, __isolated=False, __cwd=cwd, **env_vars
)
if verbose > 1:
print('Output from test script %r:' % script_exec_args)
print(repr(err))
print('Expected output: %r' % expected_msg)
self.assertIn(expected_msg.encode('utf-8'), err)
def test_dash_c_loader(self):
rc, out, err = assert_python_ok("-c", "print(__loader__)")
expected = repr(importlib.machinery.BuiltinImporter).encode("utf-8")
self.assertIn(expected, out)
def test_stdin_loader(self):
# Unfortunately, there's no way to automatically test the fully
# interactive REPL, since that code path only gets executed when
# stdin is an interactive tty.
p = spawn_python()
try:
p.stdin.write(b"print(__loader__)\n")
p.stdin.flush()
finally:
out = kill_python(p)
expected = repr(importlib.machinery.BuiltinImporter).encode("utf-8")
self.assertIn(expected, out)
@contextlib.contextmanager
def interactive_python(self, separate_stderr=False):
if separate_stderr:
p = spawn_python('-i', bufsize=1, stderr=subprocess.PIPE)
stderr = p.stderr
else:
p = spawn_python('-i', bufsize=1, stderr=subprocess.STDOUT)
stderr = p.stdout
try:
# Drain stderr until prompt
while True:
data = stderr.read(4)
if data == b">>> ":
break
stderr.readline()
yield p
finally:
kill_python(p)
stderr.close()
def check_repl_stdout_flush(self, separate_stderr=False):
with self.interactive_python(separate_stderr) as p:
p.stdin.write(b"print('foo')\n")
p.stdin.flush()
self.assertEqual(b'foo', p.stdout.readline().strip())
def check_repl_stderr_flush(self, separate_stderr=False):
with self.interactive_python(separate_stderr) as p:
p.stdin.write(b"1/0\n")
p.stdin.flush()
stderr = p.stderr if separate_stderr else p.stdout
self.assertIn(b'Traceback ', stderr.readline())
self.assertIn(b'File "<stdin>"', stderr.readline())
self.assertIn(b'ZeroDivisionError', stderr.readline())
def test_repl_stdout_flush(self):
self.check_repl_stdout_flush()
def test_repl_stdout_flush_separate_stderr(self):
self.check_repl_stdout_flush(True)
def test_repl_stderr_flush(self):
self.check_repl_stderr_flush()
def test_repl_stderr_flush_separate_stderr(self):
self.check_repl_stderr_flush(True)
def test_basic_script(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'script')
self._check_script(script_name, script_name, script_name,
script_dir, None,
importlib.machinery.SourceFileLoader)
def test_script_compiled(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'script')
py_compile.compile(script_name, doraise=True)
os.remove(script_name)
pyc_file = support.make_legacy_pyc(script_name)
self._check_script(pyc_file, pyc_file,
pyc_file, script_dir, None,
importlib.machinery.SourcelessFileLoader)
def test_directory(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, '__main__')
self._check_script(script_dir, script_name, script_dir,
script_dir, '',
importlib.machinery.SourceFileLoader)
def test_directory_compiled(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, '__main__')
py_compile.compile(script_name, doraise=True)
os.remove(script_name)
pyc_file = support.make_legacy_pyc(script_name)
self._check_script(script_dir, pyc_file, script_dir,
script_dir, '',
importlib.machinery.SourcelessFileLoader)
def test_directory_error(self):
with support.temp_dir() as script_dir:
msg = "can't find '__main__' module in %r" % script_dir
self._check_import_error(script_dir, msg)
def test_zipfile(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, '__main__')
zip_name, run_name = make_zip_script(script_dir, 'test_zip', script_name)
self._check_script(zip_name, run_name, zip_name, zip_name, '',
zipimport.zipimporter)
def test_zipfile_compiled(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, '__main__')
compiled_name = py_compile.compile(script_name, doraise=True)
zip_name, run_name = make_zip_script(script_dir, 'test_zip', compiled_name)
self._check_script(zip_name, run_name, zip_name, zip_name, '',
zipimport.zipimporter)
def test_zipfile_error(self):
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'not_main')
zip_name, run_name = make_zip_script(script_dir, 'test_zip', script_name)
msg = "can't find '__main__' module in %r" % zip_name
self._check_import_error(zip_name, msg)
def test_module_in_package(self):
with support.temp_dir() as script_dir:
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir)
script_name = _make_test_script(pkg_dir, 'script')
self._check_script(["-m", "test_pkg.script"], script_name, script_name,
script_dir, 'test_pkg',
importlib.machinery.SourceFileLoader,
cwd=script_dir)
def test_module_in_package_in_zipfile(self):
with support.temp_dir() as script_dir:
zip_name, run_name = _make_test_zip_pkg(script_dir, 'test_zip', 'test_pkg', 'script')
self._check_script(["-m", "test_pkg.script"], run_name, run_name,
script_dir, 'test_pkg', zipimport.zipimporter,
PYTHONPATH=zip_name, cwd=script_dir)
def test_module_in_subpackage_in_zipfile(self):
with support.temp_dir() as script_dir:
zip_name, run_name = _make_test_zip_pkg(script_dir, 'test_zip', 'test_pkg', 'script', depth=2)
self._check_script(["-m", "test_pkg.test_pkg.script"], run_name, run_name,
script_dir, 'test_pkg.test_pkg',
zipimport.zipimporter,
PYTHONPATH=zip_name, cwd=script_dir)
def test_package(self):
with support.temp_dir() as script_dir:
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir)
script_name = _make_test_script(pkg_dir, '__main__')
self._check_script(["-m", "test_pkg"], script_name,
script_name, script_dir, 'test_pkg',
importlib.machinery.SourceFileLoader,
cwd=script_dir)
def test_package_compiled(self):
with support.temp_dir() as script_dir:
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir)
script_name = _make_test_script(pkg_dir, '__main__')
compiled_name = py_compile.compile(script_name, doraise=True)
os.remove(script_name)
pyc_file = support.make_legacy_pyc(script_name)
self._check_script(["-m", "test_pkg"], pyc_file,
pyc_file, script_dir, 'test_pkg',
importlib.machinery.SourcelessFileLoader,
cwd=script_dir)
def test_package_error(self):
with support.temp_dir() as script_dir:
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir)
msg = ("'test_pkg' is a package and cannot "
"be directly executed")
self._check_import_error(["-m", "test_pkg"], msg, cwd=script_dir)
def test_package_recursion(self):
with support.temp_dir() as script_dir:
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir)
main_dir = os.path.join(pkg_dir, '__main__')
make_pkg(main_dir)
msg = ("Cannot use package as __main__ module; "
"'test_pkg' is a package and cannot "
"be directly executed")
self._check_import_error(["-m", "test_pkg"], msg, cwd=script_dir)
def test_issue8202(self):
# Make sure package __init__ modules see "-m" in sys.argv0 while
# searching for the module to execute
with support.temp_dir() as script_dir:
with support.change_cwd(path=script_dir):
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir, "import sys; print('init_argv0==%r' % sys.argv[0])")
script_name = _make_test_script(pkg_dir, 'script')
rc, out, err = assert_python_ok('-m', 'test_pkg.script', *example_args, __isolated=False)
if verbose > 1:
print(repr(out))
expected = "init_argv0==%r" % '-m'
self.assertIn(expected.encode('utf-8'), out)
self._check_output(script_name, rc, out,
script_name, script_name, script_dir, 'test_pkg',
importlib.machinery.SourceFileLoader)
def test_issue8202_dash_c_file_ignored(self):
# Make sure a "-c" file in the current directory
# does not alter the value of sys.path[0]
with support.temp_dir() as script_dir:
with support.change_cwd(path=script_dir):
with open("-c", "w") as f:
f.write("data")
rc, out, err = assert_python_ok('-c',
'import sys; print("sys.path[0]==%r" % sys.path[0])',
__isolated=False)
if verbose > 1:
print(repr(out))
expected = "sys.path[0]==%r" % ''
self.assertIn(expected.encode('utf-8'), out)
def test_issue8202_dash_m_file_ignored(self):
# Make sure a "-m" file in the current directory
# does not alter the value of sys.path[0]
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'other')
with support.change_cwd(path=script_dir):
with open("-m", "w") as f:
f.write("data")
rc, out, err = assert_python_ok('-m', 'other', *example_args,
__isolated=False)
self._check_output(script_name, rc, out,
script_name, script_name, script_dir, '',
importlib.machinery.SourceFileLoader)
def test_issue20884(self):
# On Windows, script with encoding cookie and LF line ending
# will be failed.
with support.temp_dir() as script_dir:
script_name = os.path.join(script_dir, "issue20884.py")
with open(script_name, "w", newline='\n') as f:
f.write("#coding: iso-8859-1\n")
f.write('"""\n')
for _ in range(30):
f.write('x'*80 + '\n')
f.write('"""\n')
with support.change_cwd(path=script_dir):
rc, out, err = assert_python_ok(script_name)
self.assertEqual(b"", out)
self.assertEqual(b"", err)
@contextlib.contextmanager
def setup_test_pkg(self, *args):
with support.temp_dir() as script_dir, \
support.change_cwd(path=script_dir):
pkg_dir = os.path.join(script_dir, 'test_pkg')
make_pkg(pkg_dir, *args)
yield pkg_dir
def check_dash_m_failure(self, *args):
rc, out, err = assert_python_failure('-m', *args, __isolated=False)
if verbose > 1:
print(repr(out))
self.assertEqual(rc, 1)
return err
def test_dash_m_error_code_is_one(self):
# If a module is invoked with the -m command line flag
# and results in an error that the return code to the
# shell is '1'
with self.setup_test_pkg() as pkg_dir:
script_name = _make_test_script(pkg_dir, 'other',
"if __name__ == '__main__': raise ValueError")
err = self.check_dash_m_failure('test_pkg.other', *example_args)
self.assertIn(b'ValueError', err)
def test_dash_m_errors(self):
# Exercise error reporting for various invalid package executions
tests = (
('builtins', br'No code object available'),
('builtins.x', br'Error while finding module specification.*'
br'ModuleNotFoundError'),
('builtins.x.y', br'Error while finding module specification.*'
br'ModuleNotFoundError.*No module named.*not a package'),
('os.path', br'loader.*cannot handle'),
('importlib', br'No module named.*'
br'is a package and cannot be directly executed'),
('importlib.nonexistant', br'No module named'),
('.unittest', br'Relative module names not supported'),
)
for name, regex in tests:
with self.subTest(name):
rc, _, err = assert_python_failure('-m', name)
self.assertEqual(rc, 1)
self.assertRegex(err, regex)
self.assertNotIn(b'Traceback', err)
def test_dash_m_bad_pyc(self):
with support.temp_dir() as script_dir, \
support.change_cwd(path=script_dir):
os.mkdir('test_pkg')
# Create invalid *.pyc as empty file
with open('test_pkg/__init__.pyc', 'wb'):
pass
err = self.check_dash_m_failure('test_pkg')
self.assertRegex(err,
br'Error while finding module specification.*'
br'ImportError.*bad magic number')
self.assertNotIn(b'is a package', err)
self.assertNotIn(b'Traceback', err)
def test_dash_m_init_traceback(self):
# These were wrapped in an ImportError and tracebacks were
# suppressed; see Issue 14285
exceptions = (ImportError, AttributeError, TypeError, ValueError)
for exception in exceptions:
exception = exception.__name__
init = "raise {0}('Exception in __init__.py')".format(exception)
with self.subTest(exception), \
self.setup_test_pkg(init) as pkg_dir:
err = self.check_dash_m_failure('test_pkg')
self.assertIn(exception.encode('ascii'), err)
self.assertIn(b'Exception in __init__.py', err)
self.assertIn(b'Traceback', err)
def test_dash_m_main_traceback(self):
# Ensure that an ImportError's traceback is reported
with self.setup_test_pkg() as pkg_dir:
main = "raise ImportError('Exception in __main__ module')"
_make_test_script(pkg_dir, '__main__', main)
err = self.check_dash_m_failure('test_pkg')
self.assertIn(b'ImportError', err)
self.assertIn(b'Exception in __main__ module', err)
self.assertIn(b'Traceback', err)
def test_pep_409_verbiage(self):
# Make sure PEP 409 syntax properly suppresses
# the context of an exception
script = textwrap.dedent("""\
try:
raise ValueError
except:
raise NameError from None
""")
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'script', script)
exitcode, stdout, stderr = assert_python_failure(script_name)
text = stderr.decode('ascii').split('\n')
self.assertEqual(len(text), 4)
self.assertTrue(text[0].startswith('Traceback'))
self.assertTrue(text[1].startswith(' File '))
self.assertTrue(text[3].startswith('NameError'))
def test_non_ascii(self):
# Mac OS X denies the creation of a file with an invalid UTF-8 name.
# Windows allows creating a name with an arbitrary bytes name, but
# Python cannot a undecodable bytes argument to a subprocess.
if (support.TESTFN_UNDECODABLE
and sys.platform not in ('win32', 'darwin')):
name = os.fsdecode(support.TESTFN_UNDECODABLE)
elif support.TESTFN_NONASCII:
name = support.TESTFN_NONASCII
else:
self.skipTest("need support.TESTFN_NONASCII")
# Issue #16218
source = 'print(ascii(__file__))\n'
script_name = _make_test_script(os.curdir, name, source)
self.addCleanup(support.unlink, script_name)
rc, stdout, stderr = assert_python_ok(script_name)
self.assertEqual(
ascii(script_name),
stdout.rstrip().decode('ascii'),
'stdout=%r stderr=%r' % (stdout, stderr))
self.assertEqual(0, rc)
def test_issue20500_exit_with_exception_value(self):
script = textwrap.dedent("""\
import sys
error = None
try:
raise ValueError('some text')
except ValueError as err:
error = err
if error:
sys.exit(error)
""")
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'script', script)
exitcode, stdout, stderr = assert_python_failure(script_name)
text = stderr.decode('ascii')
self.assertEqual(text, "some text")
def test_syntaxerror_unindented_caret_position(self):
script = "1 + 1 = 2\n"
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'script', script)
exitcode, stdout, stderr = assert_python_failure(script_name)
text = io.TextIOWrapper(io.BytesIO(stderr), 'ascii').read()
# Confirm that the caret is located under the first 1 character
self.assertIn("\n 1 + 1 = 2\n ^", text)
def test_syntaxerror_indented_caret_position(self):
script = textwrap.dedent("""\
if True:
1 + 1 = 2
""")
with support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, 'script', script)
exitcode, stdout, stderr = assert_python_failure(script_name)
text = io.TextIOWrapper(io.BytesIO(stderr), 'ascii').read()
# Confirm that the caret is located under the first 1 character
self.assertIn("\n 1 + 1 = 2\n ^", text)
# Try the same with a form feed at the start of the indented line
script = (
"if True:\n"
"\f 1 + 1 = 2\n"
)
script_name = _make_test_script(script_dir, "script", script)
exitcode, stdout, stderr = assert_python_failure(script_name)
text = io.TextIOWrapper(io.BytesIO(stderr), "ascii").read()
self.assertNotIn("\f", text)
self.assertIn("\n 1 + 1 = 2\n ^", text)
def test_consistent_sys_path_for_direct_execution(self):
# This test case ensures that the following all give the same
# sys.path configuration:
#
# ./python -s script_dir/__main__.py
# ./python -s script_dir
# ./python -I script_dir
script = textwrap.dedent("""\
import sys
for entry in sys.path:
print(entry)
""")
# Always show full path diffs on errors
self.maxDiff = None
with support.temp_dir() as work_dir, support.temp_dir() as script_dir:
script_name = _make_test_script(script_dir, '__main__', script)
# Reference output comes from directly executing __main__.py
# We omit PYTHONPATH and user site to align with isolated mode
p = spawn_python("-Es", script_name, cwd=work_dir)
out_by_name = kill_python(p).decode().splitlines()
self.assertEqual(out_by_name[0], script_dir)
self.assertNotIn(work_dir, out_by_name)
# Directory execution should give the same output
p = spawn_python("-Es", script_dir, cwd=work_dir)
out_by_dir = kill_python(p).decode().splitlines()
self.assertEqual(out_by_dir, out_by_name)
# As should directory execution in isolated mode
p = spawn_python("-I", script_dir, cwd=work_dir)
out_by_dir_isolated = kill_python(p).decode().splitlines()
self.assertEqual(out_by_dir_isolated, out_by_dir, out_by_name)
def test_consistent_sys_path_for_module_execution(self):
# This test case ensures that the following both give the same
# sys.path configuration:
# ./python -sm script_pkg.__main__
# ./python -sm script_pkg
#
# And that this fails as unable to find the package:
# ./python -Im script_pkg
script = textwrap.dedent("""\
import sys
for entry in sys.path:
print(entry)
""")
# Always show full path diffs on errors
self.maxDiff = None
with support.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
script_name = _make_test_script(script_dir, '__main__', script)
# Reference output comes from `-m script_pkg.__main__`
# We omit PYTHONPATH and user site to better align with the
# direct execution test cases
p = spawn_python("-sm", "script_pkg.__main__", cwd=work_dir)
out_by_module = kill_python(p).decode().splitlines()
self.assertEqual(out_by_module[0], work_dir)
self.assertNotIn(script_dir, out_by_module)
# Package execution should give the same output
p = spawn_python("-sm", "script_pkg", cwd=work_dir)
out_by_package = kill_python(p).decode().splitlines()
self.assertEqual(out_by_package, out_by_module)
# Isolated mode should fail with an import error
exitcode, stdout, stderr = assert_python_failure(
"-Im", "script_pkg", cwd=work_dir
)
traceback_lines = stderr.decode().splitlines()
self.assertIn("No module named script_pkg", traceback_lines[-1])
def test_nonexisting_script(self):
# bpo-34783: "./python script.py" must not crash
# if the script file doesn't exist.
# (Skip test for macOS framework builds because sys.excutable name
# is not the actual Python executable file name.
script = 'nonexistingscript.py'
self.assertFalse(os.path.exists(script))
proc = spawn_python(script, text=True,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = proc.communicate()
self.assertIn(": can't open file ", err)
self.assertNotEqual(proc.returncode, 0)
def test_main():
support.run_unittest(CmdLineTest)
support.reap_children()
if __name__ == '__main__':
test_main()