test_defopt.py

import builtins
import contextlib
import inspect
import multiprocessing as mp
import re
import runpy
import subprocess
import sys
import tokenize
import types
import typing
import unittest
from concurrent.futures import ProcessPoolExecutor
from contextlib import ExitStack
from enum import Enum
from io import StringIO
from pathlib import Path

from docutils.utils import SystemMessage

import defopt
from defopt import __version__, _options
from examples import (
    annotations, booleans, choices, exceptions, lists, parsers, short,
    starargs, styles)


Choice = Enum('Choice', [('one', 1), ('two', 2), ('%', 0.01)])
Pair = typing.NamedTuple('Pair', [('first', int), ('second', str)])


def _parse_none(i):
    if i.lower() == ':none:':
        return None
    else:
        raise ValueError(f'{i} is not a valid None string')


# Also check that the Attributes section doesn't trip docutils.
class ConstructibleFromStr:
    """
    Attributes
    ----------
    s : str
        The s.
    """

    def __init__(self, s):
        """:type s: str"""
        self.s = s


class NotConstructibleFromStr:
    def __init__(self, s):
        pass


class TestDefopt(unittest.TestCase):
    def test_main(self):
        def main(foo):
            """:type foo: str"""
            return foo
        self.assertEqual(defopt.run(main, argv=['foo']), 'foo')

    def test_subcommands(self):
        def sub(*bar):
            """:type bar: float"""
            return bar
        def sub_with_dash(*, baz=None):
            """:type baz: int"""
            return baz
        self.assertEqual(
            defopt.run([sub, sub_with_dash], argv=['sub', '1.1']), (1.1,))
        self.assertEqual(
            defopt.run([sub, sub_with_dash],
                       argv=['sub-with-dash', '--baz', '1']), 1)
        self.assertEqual(
            defopt.run({"sub1": sub, "sub_2": sub_with_dash},
                       argv=['sub1', '1.2']), (1.2,))
        self.assertEqual(
            defopt.run({"sub1": sub, "sub_2": sub_with_dash},
                       argv=['sub_2', '--baz', '1']), 1)

    def test_nested_lists_invalid(self):
        def sub1(*bar):
            """:type bar: float"""
        def subsub1(*, baz=None):
            """:type baz: int"""
        def subsub2(*foo):
            """:type foo: float"""
        with self.assertRaises(ValueError):
            defopt.run([sub1, [subsub1, subsub2]], argv=['sub1', '1.2'])

    def test_nested_subcommands1(self):
        def sub1(*bar):
            """:type bar: float"""
            return bar
        def subsub1(*, baz=None):
            """:type baz: int"""
            return baz
        def subsub2(*foo):
            """:type foo: float"""
            return foo
        self.assertEqual(
            defopt.run({"sub-1": [sub1], "sub-2": [subsub1, subsub2]},
                       argv=['sub-1', 'sub1', '1.2']), (1.2,))
        self.assertEqual(
            defopt.run({"sub-1": [sub1], "sub-2": [subsub1, subsub2]},
                       argv=['sub-2', 'subsub1', '--baz', '1']), 1)
        self.assertEqual(
            defopt.run({"sub-1": [sub1], "sub-2": [subsub1, subsub2]},
                       argv=['sub-2', 'subsub2', '1.5']), (1.5,))

    def test_nested_subcommands2(self):
        def sub1(*bar):
            """:type bar: float"""
            return bar
        def subsub1(*, baz=None):
            """:type baz: int"""
            return baz
        def subsub2(*foo):
            """:type foo: float"""
            return foo
        self.assertEqual(
            defopt.run({"sub-1": sub1, "sub-2": [subsub1, subsub2]},
                       argv=['sub-1', '1.2']), (1.2,))
        self.assertEqual(
            defopt.run({"sub1": sub1, "sub-2": [subsub1, subsub2]},
                       argv=['sub-2', 'subsub1', '--baz', '1']), 1)
        self.assertEqual(
            defopt.run({"sub1": sub1, "sub-2": [subsub1, subsub2]},
                       argv=['sub-2', 'subsub2', '1.5']), (1.5,))

    def test_nested_subcommands3(self):
        def sub1(*bar):
            """:type bar: float"""
            return bar
        def subsub1(*, baz=None):
            """:type baz: int"""
            return baz
        def subsub2(*foo):
            """:type foo: float"""
            return foo
        self.assertEqual(
            defopt.run({"sub-1": sub1,
                        "sub-2": {'subsub1': subsub1, 'subsub2': subsub2}},
                       argv=['sub-1', '1.2']), (1.2,))
        self.assertEqual(
            defopt.run({"sub-1": sub1,
                        "sub-2": {'subsub1': subsub1, 'subsub2': subsub2}},
                       argv=['sub-2', 'subsub1', '--baz', '1']), 1)
        self.assertEqual(
            defopt.run({"sub-1": sub1,
                        "sub-2": {'subsub1': subsub1, 'subsub2': subsub2}},
                       argv=['sub-2', 'subsub2', '1.5']), (1.5,))

    def test_nested_subcommands_deep(self):
        def sub(*bar):
            """:type bar: float"""
            return bar
        self.assertEqual(
            defopt.run({'a': {'b': {'c': {'d': {'e': sub}}}}},
                       argv=['a', 'b', 'c', 'd', 'e', '1.2']), (1.2,))
        self.assertEqual(
            defopt.run({'a': {'b': {'c': {'d': {'e': [sub]}}}}},
                       argv=['a', 'b', 'c', 'd', 'e', 'sub', '1.2']), (1.2,))

    def test_nested_subcommands_mixed_invalid1(self):
        def sub1(*bar):
            """:type bar: float"""
        def subsub1(*, baz=None):
            """:type baz: int"""
        def subsub2(*foo):
            """:type foo: float"""
        with self.assertRaises(ValueError):
            defopt.run([sub1, {'sub2': [subsub1, subsub2]}],
                        argv=['sub1', '1.2'])
        with self.assertRaises(ValueError):
            defopt.run([sub1, {'sub2': [subsub1, subsub2]}],
                       argv=['sub2', 'subsub1', '--baz', '1'])
        with self.assertRaises(ValueError):
            defopt.run([sub1, {'sub2': [subsub1, subsub2]}],
                       argv=['sub2', 'subsub2', '1.1'])

    def test_nested_subcommands_mixed_invalid2(self):
        def sub(*bar):
            """:type bar: float"""
        def subsub_with_dash(*, baz=None):
            """:type baz: int"""
        def subsub(*foo):
            """:type foo: float"""
        with self.assertRaises(ValueError):
            defopt.run([sub, {'subsub1': subsub_with_dash, 'subsub2': subsub}],
                       argv=['sub', '1.2'])
        with self.assertRaises(ValueError):
            defopt.run([sub, {'subsub1': subsub_with_dash, 'subsub2': subsub}],
                       argv=['subsub1', '--baz', '1'])
        with self.assertRaises(ValueError):
            defopt.run([sub, {'subsub1': subsub_with_dash, 'subsub2': subsub}],
                       argv=['subsub2', '1.5'])

    def test_var_positional(self):
        for doc in [
                ":type foo: int", r":type \*foo: int", ":param int foo: doc"]:
            def main(*foo): return foo
            main.__doc__ = doc
            self.assertEqual(defopt.run(main, argv=['1', '2']), (1, 2))
            self.assertEqual(defopt.run(main, argv=[]), ())

    def test_no_default(self):
        def main(a):
            """:type a: str"""
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[])

    def test_keyword_only(self):
        def main(foo='bar', *, baz='quux'):
            """
            :type foo: str
            :type baz: str
            """
            return foo, baz
        self.assertEqual(defopt.run(main, argv=['FOO', '--baz', 'BAZ']),
                         ('FOO', 'BAZ'))
        self.assertEqual(defopt.run(main, argv=[]), ('bar', 'quux'))

    def test_keyword_only_no_default(self):
        def main(*, foo):
            """:type foo: str"""
            return foo
        self.assertEqual(defopt.run(main, argv=['--foo', 'baz']), 'baz')
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[])

    def test_var_keywords(self):
        def bad(**kwargs):
            """:type kwargs: str"""

        with self.assertRaises(ValueError):
            defopt.run(bad)

    def test_bad_arg(self):
        with self.assertRaises(TypeError):
            defopt.run(foo=None)

    def test_no_subparser_specified(self):
        def sub1(): assert False
        def sub2(): assert False
        with self.assertRaises(SystemExit):
            defopt.run([sub1, sub2], argv=[])

    def test_no_param_doc(self):
        def bad(foo):
            """Test function"""
        with self.assertRaisesRegex(ValueError, 'type.*foo'):
            defopt.run(bad, argv=['foo'])

    def test_no_type_doc(self):
        def bad(foo):
            """:param foo: no type info"""
        with self.assertRaisesRegex(ValueError, 'type.*foo'):
            defopt.run(bad, argv=['foo'])

    def test_return(self):
        def one(): return 1
        def none(): pass
        self.assertEqual(defopt.run([one, none], argv=['one']), 1)
        self.assertEqual(defopt.run([one, none], argv=['none']), None)

    def test_underscores(self):
        def main(a_b_c, *, d_e_f=None):
            """Test function

            :type a_b_c: int
            :type d_e_f: int
            """
            return a_b_c, d_e_f
        self.assertEqual(defopt.run(main, argv=['1', '--d-e-f', '2']), (1, 2))

    def test_private_with_default(self):
        def main(_a=None): pass
        defopt.run(main, argv=[])

    def test_private_without_default(self):
        def main(_a: int): assert False
        with self.assertRaisesRegex(ValueError,
                                    # Older Pythons have no space post-colon.
                                    r'parameter _a of main\(_a: ?int\) is '
                                    r'private but has no default'):
            defopt.run(main, argv=[])

    def test_argparse_kwargs(self):
        def main(*, a=None):
            """:type a: str"""
            return a
        self.assertEqual(
            defopt.run(main, argparse_kwargs={'prefix_chars': '+'},
                       argv=['+a', 'foo']),
            'foo')

    def test_intermixed(self):
        def main(*args: int, key: str): return args, key
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['1', '-kk', '2'])
        if sys.version_info >= (3, 7):
            self.assertEqual(
                defopt.run(main, argv=['1', '-kk', '2'], intermixed=True),
                ((1, 2), 'k'))
        else:
            with self.assertRaises(RuntimeError):
                defopt.run(main, argv=['1', '-kk', '2'], intermixed=True)


class TestBindKnown(unittest.TestCase):
    def test_bind_known(self):
        def main(*args: int, key: str): return args, key
        call, rest = defopt.bind_known(
            main, argv=['1', '2', '-kk', '-qq'])
        self.assertEqual((call(), rest), (((1, 2), 'k'), ['-qq']))
        call, rest = defopt.bind_known(
            main, argv=['1', '-kk', '2', '-qq'])
        self.assertEqual((call(), rest), (((1,), 'k'), ['2', '-qq']))
        if sys.version_info >= (3, 7):
            call, rest = defopt.bind_known(
                main, argv=['1', '-kk', '2', '-qq'], intermixed=True)
            self.assertEqual((call(), rest), (((1, 2), 'k'), ['-qq']))


class TestParsers(unittest.TestCase):
    def test_parser(self):
        def main(value):
            """:type value: int"""
            return value
        self.assertEqual(defopt.run(main, argv=['1']), 1)

    def test_overridden_parser(self):
        def parser(string):
            return int(string) * 2
        def main(value):
            """:type value: int"""
            return value
        self.assertEqual(
            defopt.run(main, parsers={int: parser}, argv=['1']), 2)

    def test_overridden_none_parser(self):
        def parser(string):
            if string == 'nil':
                return None
            else:
                raise ValueError("Not nil")
        def main(ints, strs):
            """
            :type ints: typing.List[typing.Optional[int]]
            :type strs: typing.List[typing.Optional[str]]
            """
            return ints, strs
        self.assertEqual(
            defopt.run(main, parsers={type(None): parser},
                       argv=['-i', 'nil', '0', '-s', 'nil', 's']),
            ([None, 0], [None, 's']))

    def test_parse_bool(self):
        parser = defopt._get_parser(bool, {})
        self.assertEqual(parser('t'), True)
        self.assertEqual(parser('FALSE'), False)
        self.assertEqual(parser('1'), True)
        with self.assertRaises(ValueError):
            parser('foo')

    def test_parse_path(self):
        def main(value):
            """:type value: Path"""
            return value
        self.assertEqual(defopt.run(main, argv=['foo']), Path('foo'))

    def test_parse_slice(self):
        parser = defopt._get_parser(slice, {})
        self.assertEqual(parser(':'), slice(None))
        self.assertEqual(parser(':1'), slice(None, 1))
        self.assertEqual(parser('"a":"b":"c"'), slice("a", "b", "c"))
        with self.assertRaises(ValueError):
            parser('1')

    def test_no_parser(self):
        with self.assertRaisesRegex(Exception, 'no parser'):
            defopt._get_parser(object, parsers={type: type})

    def test_containers(self):
        def main(foo, bar):
            """
            :type foo: tuple[float]
            :type bar: list[float]
            """
            return foo, bar
        self.assertEqual(defopt.run(main, argv=['1.1', '--bar', '2.2', '3.3']),
                         ((1.1,), [2.2, 3.3]))

    def test_list_kwarg(self):
        def main(foo=None):
            """:type foo: list[float]"""
            return foo
        self.assertEqual(
            defopt.run(main, argv=['--foo', '1.1', '2.2']), [1.1, 2.2])

    def test_list_bare(self):
        with self.assertRaises(ValueError):
            defopt._get_parser(list, {})

    def test_list_keyword_only(self):
        def main(*, foo):
            """:type foo: list[int]"""
            return foo
        self.assertEqual(defopt.run(main, argv=['--foo', '1', '2']), [1, 2])
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[])

    def test_list_var_positional(self):
        def modern(*foo):
            """:type foo: typing.Iterable[int]"""
            return foo
        def legacy(*foo):
            """:type foo: list[int]"""
            return foo
        for func in modern, legacy:
            out = defopt.run(func, argv=['--foo', '1', '--foo', '2', '3'])
            self.assertEqual(out, ([1], [2, 3]))
            self.assertEqual(defopt.run(func, argv=[]), ())

    def test_bool(self):
        def main(foo):
            """:type foo: bool"""
            return foo
        self.assertIs(defopt.run(main, argv=['1']), True)
        self.assertIs(defopt.run(main, argv=['0']), False)
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[])

    def test_bool_optional(self):
        def main(foo=None):
            """:type foo: typing.Optional[bool]"""
            return foo
        self.assertIs(defopt.run(main, argv=['1'],
                                 parsers={type(None): _parse_none}), True)
        self.assertIs(defopt.run(main, argv=['0'],
                                 parsers={type(None): _parse_none}), False)
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[':none:'])
        self.assertIs(defopt.run(main, argv=[':none:'],
                                 parsers={type(None): _parse_none}), None)
        self.assertIs(defopt.run(main, argv=[],
                                 parsers={type(None): _parse_none}), None)

    def test_bool_optional_keyword_none(self):
        def main(*, foo=None):
            """:type foo: typing.Optional[bool]"""
            return foo
        self.assertIs(defopt.run(main, argv=['--foo']), True)
        self.assertIs(defopt.run(main, argv=['--no-foo']), False)
        self.assertIs(defopt.run(main, argv=[]), None)

    def test_bool_optional_keyword_true(self):
        def main(*, foo=True):
            """:type foo: typing.Optional[bool]"""
            return foo
        # cannot get a None value in this case from the CLI
        self.assertIs(defopt.run(main, argv=['--foo']), True)
        self.assertIs(defopt.run(main, argv=['--no-foo']), False)
        self.assertIs(defopt.run(main, argv=[]), True)

    def test_bool_optional_keyword_false(self):
        def main(*, foo=False):
            """:type foo: typing.Optional[bool]"""
            return foo
        self.assertIs(defopt.run(main, argv=['--foo']), True)
        self.assertIs(defopt.run(main, argv=['--no-foo']), False)
        self.assertIs(defopt.run(main, argv=[]), False)

    def test_bool_optional_keyword_none_no_negated_flags(self):
        def main(*, foo=None):
            """:type foo: typing.Optional[bool]"""
            return foo
        self.assertIs(defopt.run(main, argv=['--foo'], no_negated_flags=True),
                      True)
        with self.assertRaises(SystemExit):
            self.assertIs(defopt.run(main, argv=['--no-foo'],
                          no_negated_flags=True), False)
        self.assertIs(defopt.run(main, argv=[], no_negated_flags=True), None)

    def test_bool_optional_keyword_true_no_negated_flags(self):
        def main(*, foo=True):
            """:type foo: typing.Optional[bool]"""
            return foo
        self.assertIs(defopt.run(main, argv=['--foo'], no_negated_flags=True),
                      True)
        # negated flag is still added, else foo could only be True
        self.assertIs(defopt.run(main, argv=['--no-foo'],
                      no_negated_flags=True), False)
        self.assertIs(defopt.run(main, argv=[], no_negated_flags=True), True)

    def test_bool_optional_keyword_false_no_negated_flags(self):
        def main(*, foo=False):
            """:type foo: typing.Optional[bool]"""
            return foo
        self.assertIs(defopt.run(main, argv=['--foo'], no_negated_flags=True),
                      True)
        with self.assertRaises(SystemExit):
            self.assertIs(defopt.run(main, argv=['--no-foo'],
                          no_negated_flags=True), False)
        self.assertIs(defopt.run(main, argv=[], no_negated_flags=True), False)

    def test_bool_list(self):
        def main(foo):
            """:type foo: list[bool]"""
            return foo
        self.assertEqual(
            defopt.run(main, argv=['--foo', '1', '0']), [True, False])

    def test_bool_var_positional(self):
        def main(*foo):
            """:type foo: bool"""
            return foo
        self.assertEqual(
            defopt.run(main, argv=['1', '1', '0']), (True, True, False))
        self.assertEqual(
            defopt.run(main, argv=[]), ())

    def test_bool_list_var_positional(self):
        def main(*foo):
            """:type foo: list[bool]"""
            return foo
        argv = ['--foo', '1', '--foo', '0', '0']
        self.assertEqual(
            defopt.run(main, argv=argv), ([True], [False, False]))
        self.assertEqual(
            defopt.run(main, argv=[]), ())

    def test_bool_kwarg(self):
        def main(foo='default'):
            """:type foo: bool"""
            return foo
        self.assertIs(defopt.run(main, cli_options='has_default',
                                 argv=[]), 'default')
        self.assertIs(defopt.run(main, cli_options='has_default',
                                 argv=['--foo']), True)
        self.assertIs(defopt.run(main, cli_options='has_default',
                                 argv=['--no-foo']), False)
        self.assertIs(defopt.run(main, cli_options='has_default',
                                 argv=['--foo', '--no-foo']), False)

    def test_bool_keyword_only(self):
        def main(*, foo):
            """:type foo: bool"""
            return foo
        self.assertIs(defopt.run(main, argv=['--foo']), True)
        self.assertIs(defopt.run(main, argv=['--no-foo']), False)
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[])

    def test_cli_options(self):
        def main(foo):
            """:type foo: bool"""
            return foo
        self.assertIs(
            defopt.run(main, cli_options='all', argv=['--foo']), True)
        self.assertIs(
            defopt.run(main, cli_options='all', argv=['--no-foo']), False)
        with self.assertRaises(SystemExit):
            defopt.run(main, cli_options='all', argv=['1'])
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['--foo'])
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['--no-foo'])
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=[])

    def test_implicit_parser(self):
        def ok(foo):
            """:type foo: ConstructibleFromStr"""
            return foo

        self.assertEqual(defopt.run(ok, argv=["foo"]).s, "foo")

    def test_implicit_noparser(self):
        def notok(foo):
            """:type foo: NotConstructibleFromStr"""

        with self.assertRaisesRegex(Exception, 'no parser.*NotConstructible'):
            defopt.run(notok, argv=["foo"])


class TestFlags(unittest.TestCase):
    def test_short_flags(self):
        def func(foo=1):
            """:type foo: int"""
            return foo
        self.assertEqual(
            defopt.run(func, short={'foo': 'f'}, cli_options='has_default',
                       argv=['-f', '2']),
            2)

    def test_short_negation(self):
        def func(*, foo=False):
            """:type foo: bool"""
            return foo
        self.assertIs(
            defopt.run(func, short={'foo': 'f', 'no-foo': 'F'}, argv=['-f']),
            True)
        self.assertIs(
            defopt.run(func, short={'foo': 'f', 'no-foo': 'F'}, argv=['-F']),
            False)

    def test_auto_short(self):
        def func(*, foo=1, bar=2, baz=3):
            """
            :type foo: int
            :type bar: int
            :type baz: int
            """
            return foo
        self.assertEqual(defopt.run(func, argv=['-f', '2']), 2)
        with self.assertRaises(SystemExit):
            defopt.run(func, argv=['-b', '2'])

    def test_auto_short_help(self):
        def func(*, hello="world"):
            """:type hello: str"""
        defopt.run(func, argv=[])
        with self.assertRaises(SystemExit):
            defopt.run(func, argv=["-h", ""])
        self.assertEqual(
            defopt.run(
                func, argparse_kwargs={"add_help": False}, argv=["-h", ""]),
            None)


class TestEnums(unittest.TestCase):
    def test_enum(self):
        def main(foo):
            """:type foo: Choice"""
            return foo
        self.assertEqual(defopt.run(main, argv=['one']), Choice.one)
        self.assertEqual(defopt.run(main, argv=['two']), Choice.two)
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['three'])

    def test_optional(self):
        def main(*, foo=None):
            """:type foo: Choice"""
            return foo
        self.assertEqual(defopt.run(main, argv=['--foo', 'one']), Choice.one)
        self.assertIs(defopt.run(main, argv=[]), None)

    def test_subcommand(self):
        def sub1(foo):
            """:type foo: Choice"""
            return foo
        def sub2(bar):
            """:type bar: Choice"""
            return bar
        self.assertEqual(
            defopt.run([sub1, sub2], argv=['sub1', 'one']), Choice.one)
        self.assertEqual(
            defopt.run([sub1, sub2], argv=['sub2', 'two']), Choice.two)


class TestTuple(unittest.TestCase):
    def test_tuple(self):
        def main(foo):
            """:param typing.Tuple[int,str] foo: foo"""
            return foo
        self.assertEqual(defopt.run(main, argv=['1', '2']), (1, '2'))

    def test_tuple_variable_length(self):
        def main(foo):
            """:param typing.Tuple[int,...] foo: foo"""
            return foo
        self.assertEqual(defopt.run(main, argv=['1', '2', '3']), (1, 2, 3))

    def test_tupleenum(self):
        def main(foo: typing.Tuple[Choice] = None):
            return foo
        self.assertEqual(defopt.run(main, argv=['one']), (Choice.one,))

    def test_namedtuple(self):
        # Add a second argument after the tuple to ensure that the converter
        # closes over the correct type.
        def main(foo, bar):
            """
            :param Pair foo: foo
            :param int bar: bar
            """
            return foo
        # Instances of the Pair class compare equal to tuples, so we compare
        # their __str__ instead to make sure that the type is correct too.
        self.assertEqual(str(defopt.run(main, argv=['1', '2', '3'])),
                         str(Pair(1, '2')))

    def test_enumnamedtuple(self):
        class EnumPair(Pair, Enum):
            a = Pair('A', 1)
            b = Pair('B', 2)

        def main(foo: EnumPair): return foo
        self.assertEqual(defopt.run(main, argv=['a']), EnumPair.a)

    def test_tuple_fails_early(self):
        def main(foo):
            """:param typing.Tuple[int,NotConstructibleFromStr] foo: foo"""
        with self.assertRaisesRegex(Exception, 'no parser'):
            defopt.run(main, argv=['-h'])


class TestUnion(unittest.TestCase):
    def test_union(self):
        def main(foo, bar=None):
            """
            :param typing.Union[int,str] foo: foo
            :param bar: bar
            :type bar: float or str
            """
            return type(foo), type(bar)
        self.assertEqual(defopt.run(main, argv=['1', '2']), (int, float))
        self.assertEqual(defopt.run(main, argv=['1', 'b']), (int, str))
        self.assertEqual(defopt.run(main, argv=['a', '2']), (str, float))

    def test_or_union(self):
        if not hasattr(types, "UnionType"):
            raise unittest.SkipTest("A|B-style unions not supported")
        def main(foo):
            """:param int|str foo: foo"""
            return type(foo)
        self.assertEqual(defopt.run(main, argv=['1']), int)
        self.assertEqual(defopt.run(main, argv=['x']), str)

    def test_bad_parse(self):
        def main(foo):
            """:param typing.Union[int,float] foo: foo"""
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['bar'])

    def test_bad_union(self):
        def main(foo):
            """:param typing.Union[int,typing.List[str]] foo: foo"""
        with self.assertRaises(ValueError):
            defopt.run(main, argv=['1'])
        def main(foo):
            """
            :param foo: foo
            :type foo: int or list[str]
            """
        with self.assertRaises(ValueError):
            defopt.run(main, argv=['1'])

    def test_not_bad_union(self):
        # get_type_hints reports a type of Union[List[int], NoneType] so check
        # that this doesn't get reported as "unsupported union including
        # container type".
        def main(foo: typing.List[int] = None): return foo
        self.assertEqual(defopt.run(main, argv=['--foo', '1']), [1])

    def test_union_infaillible_and_unparseable(self):
        def main(foo: typing.Union[str, NotConstructibleFromStr],
                 bar: typing.Union[Path, NotConstructibleFromStr]):
            return foo, bar
        self.assertEqual(defopt.run(main, argv=['a', 'b']), ('a', Path('b')))

    def test_union_unparseable_and_infaillible(self):
        def main(foo: typing.Union[NotConstructibleFromStr, str]): return foo
        with self.assertRaises(Exception):
            defopt.run(main, argv=['foo'])
        def main(foo: typing.Union[NotConstructibleFromStr, Path]): return foo
        with self.assertRaises(Exception):
            defopt.run(main, argv=['foo'])


class TestOptional(unittest.TestCase):
    def test_optional_hint_list(self):
        def main(op: typing.Optional[typing.List[str]]): return op
        self.assertEqual(defopt.run(main, argv=['--op', '1', '2']), ['1', '2'])

    def test_optional_hint_tuple(self):
        def main(op: typing.Optional[typing.Tuple[int]]): return op
        self.assertEqual(defopt.run(main, argv=['1']), (1,))

    def test_optional_doc_list(self):
        def main(op):
            """:param typing.Optional[typing.List[int]] op: op"""
            return op
        self.assertEqual(defopt.run(main, argv=['--op', '1', '2']), [1, 2])

    def test_optional_doc_tuple(self):
        def main(op):
            """:param typing.Optional[typing.Tuple[str]] op: op"""
            return op
        self.assertEqual(defopt.run(main, argv=['1']), ('1',))

    def test_union_operator_hint_list(self):
        if not hasattr(types, "UnionType"):
            raise unittest.SkipTest("A|B-style unions not supported")
        def main(op: typing.List[str] | None): return op
        self.assertEqual(defopt.run(main, argv=['--op', '1', '2']), ['1', '2'])

    def test_union_operator_hint_tuple(self):
        if not hasattr(types, "UnionType"):
            raise unittest.SkipTest("A|B-style unions not supported")
        def main(op: typing.Tuple[int] | None): return op
        self.assertEqual(defopt.run(main, argv=['1']), (1,))

    def test_union_operator_doc_list(self):
        if not hasattr(types, "UnionType"):
            raise unittest.SkipTest("A|B-style unions not supported")
        def main(op):
            """:param list[int]|None op: op"""
            return op
        self.assertEqual(defopt.run(main, argv=['--op', '1', '2']), [1, 2])

    def test_union_operator_doc_one_item_tuple(self):
        if not hasattr(types, "UnionType"):
            raise unittest.SkipTest("A|B-style unions not supported")
        def main(op):
            """:param tuple[int]|None op: op"""
            return op
        self.assertEqual(defopt.run(main, argv=['1']), (1,))

    def test_union_operator_doc_multiple_item_tuple(self):
        if not hasattr(types, "UnionType"):
            raise unittest.SkipTest("A|B-style unions not supported")
        def main(op):
            """:param tuple[str,str]|None op: op"""
            return op
        self.assertEqual(defopt.run(main, argv=['a', 'b']), ('a', 'b'))

    def test_multiple_item_optional_tuple_none_parser(self):
        def main(op):
            """:param typing.Optional[typing.Tuple[int, int]] op: op"""
        with self.assertRaises(ValueError):
            defopt.run(main, argv=['1', '2'],
                       parsers={type(None): _parse_none})

    def test_one_item_optional_tuple_none_parser(self):
        def main(op):
            """:param typing.Optional[typing.Tuple[int]] op: op"""
            return op
        self.assertEqual(defopt.run(main, argv=['1'],
                                    parsers={type(None): _parse_none}),
                         (1,))
        self.assertEqual(defopt.run(main, argv=[':none:'],
                                    parsers={type(None): _parse_none}),
                         None)
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['foo'],
                       parsers={type(None): _parse_none})


class TestLiteral(unittest.TestCase):
    def test_literal(self):
        def main(foo):
            """:param defopt.Literal[Choice.one,"bar","baz"] foo: foo"""
            return foo
        self.assertEqual(defopt.run(main, argv=['bar']), 'bar')
        self.assertEqual(defopt.run(main, argv=['one']), Choice.one)
        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['quux'])


class TestExceptions(unittest.TestCase):
    def test_exceptions(self):
        def main(name):
            """
            :param str name: name
            :raises RuntimeError:
            """
            raise getattr(builtins, name)('oops')

        with self.assertRaises(SystemExit):
            defopt.run(main, argv=['RuntimeError'])
        with self.assertRaises(ValueError):
            defopt.run(main, argv=['ValueError'])


class TestDoc(unittest.TestCase):
    def test_parse_docstring(self):
        doc = """
        Test function

        :param one: first param
        :type one: int
        :param float two: second param
        :returns: str
        :junk one two: nothing
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self.assertEqual(doc_sig.doc, 'Test function\n\n')
        one = doc_sig.parameters['one']
        self.assertEqual(one.doc, 'first param')
        self.assertEqual(one.annotation, 'int')
        two = doc_sig.parameters['two']
        self.assertEqual(two.doc, 'second param')
        self.assertEqual(two.annotation, 'float')

    def test_parse_params(self):
        doc = """
        Test function

        :param first: first param
        :parameter int second: second param
        :arg third: third param
        :argument float fourth: fourth param
        :key fifth: fifth param
        :keyword str sixth: sixth param
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self.assertEqual(doc_sig.parameters['first'].doc, 'first param')
        self.assertEqual(doc_sig.parameters['second'].doc, 'second param')
        self.assertEqual(doc_sig.parameters['third'].doc, 'third param')
        self.assertEqual(doc_sig.parameters['fourth'].doc, 'fourth param')
        self.assertEqual(doc_sig.parameters['fifth'].doc, 'fifth param')
        self.assertEqual(doc_sig.parameters['sixth'].doc, 'sixth param')

    def test_parse_doubles(self):
        doc = """
        Test function

        :param int param: the parameter
        :type param: int
        """
        with self.assertRaises(ValueError):
            defopt._parse_docstring(inspect.cleandoc(doc))

        doc = """Test function

        :type param: int
        :param int param: the parameter
        """
        with self.assertRaises(ValueError):
            defopt._parse_docstring(inspect.cleandoc(doc))

    def test_no_doc(self):
        doc_sig = defopt._parse_docstring(None)
        self.assertEqual(doc_sig.doc, '')
        self.assertEqual(doc_sig.parameters, {})

    def test_param_only(self):
        doc_sig = defopt._parse_docstring(""":param int param: test""")
        self.assertEqual(doc_sig.doc, '')
        param = doc_sig.parameters['param']
        self.assertEqual(param.doc, 'test')
        self.assertEqual(param.annotation, 'int')

    def test_implicit_role(self):
        doc_sig = defopt._parse_docstring("""start `int` end""")
        self.assertEqual(doc_sig.doc, 'start \033[4mint\033[0m end\n\n')

    def test_explicit_role(self):
        doc_sig = defopt._parse_docstring(
            """start :py:class:`int` :kbd:`ctrl` end""")
        self.assertEqual(doc_sig.doc, 'start int ctrl end\n\n')

    def test_sphinx(self):
        doc = """
        One line summary.

        Extended description.

        :param int arg1: Description of arg1
        :param str arg2: Description of arg2

            And more about arg2
        :keyword float arg3: Description of arg3
        :returns: Description of return value.
        :rtype: str

        .. rubric:: examples

        >>> print("hello, world")
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self._check_doc(doc_sig)

    def test_google(self):
        # Docstring modified from Napoleon's example.
        doc = """
        One line summary.

        Extended description.

        Args:
          arg1(int): Description of arg1
          arg2(str): Description of arg2

            And more about arg2

        Keyword Arguments:
          arg3(float): Description of arg3

        Returns:
          str: Description of return value.

        Examples:
          >>> print("hello, world")
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self._check_doc(doc_sig)

    def test_numpy(self):
        # Docstring modified from Napoleon's example.
        doc = """
        One line summary.

        Extended description.

        Parameters
        ----------
        arg1 : int
            Description of arg1
        arg2 : str
            Description of arg2

            And more about arg2

        Keyword Arguments
        -----------------
        arg3 : float
            Description of arg3

        Returns
        -------
        str
            Description of return value.

        Examples
        --------
        >>> print("hello, world")
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self._check_doc(doc_sig)

    def _check_doc(self, doc_sig):
        self.assertEqual(
            doc_sig.doc,
            'One line summary.\n\nExtended description.\n\n'
            'examples:\n\n>>> print("hello, world")\n\n')
        self.assertEqual(len(doc_sig.parameters), 3)
        self.assertEqual(doc_sig.parameters['arg1'].doc, 'Description of arg1')
        self.assertEqual(doc_sig.parameters['arg1'].annotation, 'int')
        self.assertEqual(doc_sig.parameters['arg2'].doc,
                         'Description of arg2\n\nAnd more about arg2')
        self.assertEqual(doc_sig.parameters['arg2'].annotation, 'str')
        self.assertEqual(doc_sig.parameters['arg3'].doc, 'Description of arg3')
        self.assertEqual(doc_sig.parameters['arg3'].annotation, 'float')

    def test_sequence(self):
        self.assertEqual(
            defopt._get_type_from_doc(
                'Sequence[int]', {'Sequence': typing.Sequence}),
            typing.List[int])

    def test_collection(self):
        self.assertEqual(
            defopt._get_type_from_doc(
                'Collection[int]', {'Collection': typing.Collection}),
            typing.List[int])

    def test_iterable(self):
        self.assertEqual(
            defopt._get_type_from_doc(
                'typing.Iterable[int]', {'typing': typing}),
            typing.List[int])

    def test_literal_block(self):
        doc = """
        ::

            Literal block
                Multiple lines

        .. code:: python

            def foo(): pass
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self.assertEqual(
            doc_sig.doc,
            '    Literal block\n        Multiple lines\n\n'
            '    def foo(): pass\n\n')

    def test_newlines(self):
        doc = """
        Bar
        Baz

        .. a comment

        - bar
        - baz

        quux::

            hello


        1. bar
        #. baz

        ii. bar
        #.  baz
        """
        doc_sig = defopt._parse_docstring(inspect.cleandoc(doc))
        self.assertEqual(doc_sig.doc, inspect.cleandoc("""\
            Bar
            Baz

            - bar

            - baz

            quux:

                hello

            1. bar

            2. baz

            ii.  bar

            iii. baz""") + "\n\n")

    def test_bad_doc(self):
        doc = """
        some
        - bad
          - indent
        """
        with self.assertRaises(SystemMessage):
            defopt._parse_docstring(inspect.cleandoc(doc))


class TestAnnotations(unittest.TestCase):
    def test_simple(self):
        self.assertEqual(defopt._get_type_from_hint(int), int)

    def test_container(self):
        self.assertEqual(defopt._get_type_from_hint(typing.Sequence[int]),
                         typing.List[int])

    def test_conflicting(self):
        def foo(bar: int):
            """:type bar: float"""
        with self.assertRaisesRegex(ValueError, 'bar.*int.*float'):
            defopt.run(foo, argv=['1'])

    def test_none(self):
        def foo(bar):
            """No type information"""
        with self.assertRaisesRegex(ValueError, 'no type'):
            defopt.run(foo, argv=['1'])

    def test_same(self):
        def foo(bar: int):
            """:type bar: int"""
            return bar
        self.assertEqual(defopt.run(foo, argv=['1']), 1)


class TestHelp(unittest.TestCase):
    def test_type(self):
        def foo(bar):
            """:param int bar: baz"""
        self.assert_in_help('(type: int)', foo, 'dt')
        self.assert_in_help('(type: int)', foo, 't')
        self.assert_not_in_help('(', foo, 'd')
        self.assert_not_in_help('(', foo, '')

    def test_enum_and_no_help(self):
        def foo(bar):
            """:param Choice bar:"""
        self.assert_not_in_help('(', foo, 'dt')
        self.assert_not_in_help('(', foo, 't')
        self.assert_not_in_help('(', foo, 'd')
        self.assert_not_in_help('(', foo, '')

    def test_default(self):
        def foo(bar=1):
            """:param int bar: baz"""
        self.assert_in_help('(type: int, default: 1)', foo, 'dt')
        self.assert_in_help('(type: int)', foo, 't')
        self.assert_in_help('(default: 1)', foo, 'd')
        self.assert_not_in_help('(', foo, '')

    def test_default_list(self):
        def foo(bar=[]):
            """:param typing.List[int] bar: baz"""
        self.assert_in_help('(type: int, default: [])', foo, 'dt')
        self.assert_in_help('(type: int)', foo, 't')
        self.assert_in_help('(default: [])', foo, 'd')
        self.assert_not_in_help('(', foo, '')

    def test_default_bool(self):
        def foo(bar=False):
            """:param bool bar: baz"""
        self.assert_in_help('(default: False)', foo, 'dt')
        self.assert_not_in_help('(', foo, 't')
        self.assert_in_help('(default: False)', foo, 'd')
        self.assert_not_in_help('(', foo, '')

    def test_no_negated_flags(self):
        def main(*, foo=False, bar=True):
            """
            :param bool foo: Foo
            :param bool bar: Bar
            """
        self.assert_not_in_help('--no-foo', main, 'n')
        self.assert_in_help('--no-bar', main, 'n')

    def test_keyword_only(self):
        def foo(*, bar):
            """:param int bar: baz"""
        self.assert_in_help('(type: int)', foo, 'dt')
        self.assert_in_help('(type: int)', foo, 't')
        self.assert_not_in_help('(', foo, 'd')
        self.assert_not_in_help('(', foo, '')

    def test_keyword_only_bool(self):
        def foo(*, bar):
            """:param bool bar: baz"""
        self.assert_not_in_help('default', foo, 'dt')

    def test_keyword_only_enum_percent_escape(self):
        def foo(*, bar=Choice['%']):
            """:param Choice bar:"""
        self.assert_not_in_help('Choice', foo, 'dt')
        self.assert_in_help('{one,two,%}', foo, 'dt')
        self.assert_not_in_help('Choice', foo, 't')
        self.assert_not_in_help('Choice', foo, 'd')
        self.assert_in_help('{one,two,%}', foo, 'd')
        self.assert_not_in_help('Choice', foo, '')
        # ("{one,two,%}" always shows up at least in the usage line.)

    def test_keyword_only_literal_percent_escape(self):
        def foo(*, bar):
            """:param defopt.Literal["1%","everything"] bar: 1%"""
        self.assert_not_in_help('Literal', foo, 'dt')
        self.assert_not_in_help('Literal', foo, 't')
        self.assert_not_in_help('Literal', foo, 'd')
        self.assert_not_in_help('Literal', foo, '')

    def test_tuple(self):
        def main(foo=None):
            """:param typing.Tuple[int,str] foo: help"""
        self.assert_in_help('--foo FOO FOO', main, '')

    def test_namedtuple(self):
        def main(foo=None):
            """:param Pair foo: help"""
        self.assert_in_help('--foo first second', main, '')

    def test_var_positional(self):
        for doc in [
                ":type bar: int", r":type \*bar: int", ":param int bar: baz"]:
            def foo(*bar): assert False
            foo.__doc__ = doc
            self.assert_not_in_help('default', foo, 'dt')

    def test_list_var_positional(self):
        def foo(*bar):
            """:param list[int] bar: baz"""
        self.assert_not_in_help('default', foo, 'dt')

    def test_private(self):
        def foo(bar, _baz=None):
            """:param int bar: bar help"""
        self.assert_not_in_help('baz', foo, 'dt')

    def test_no_interpolation(self):
        def foo(bar):
            """:param int bar: %(prog)s"""
        self.assert_in_help('%(prog)s', foo, '')
        self.assert_not_in_help('%%', foo, '')

    def test_hyperlink_plaintext(self):
        def foo():
            """This site https://www.python.org/ is cool"""
        self.assert_in_help(
            "This site https://www.python.org/ is cool",
            foo,
            ""
        )

    def test_hyperlink_target_embedded(self):
        def foo():
            """`This site <https://www.python.org/>`_ is cool"""
        self.assert_in_help(
            "This site (https://www.python.org/) is cool",
            foo,
            ""
        )

    def test_hyperlink_target_separated(self):
        def foo():
            """This site_ is cool

            .. _site: https://www.python.org/
            """
        self.assert_in_help("This site is cool", foo, "")
        self.assert_not_in_help("https://www.python.org/", foo, "")

    def test_rst_ansi(self):
        def foo():
            """**bold** *italic* `underlined`"""
        self.assert_in_help(
            '\033[1mbold\033[0m \033[3mitalic\033[0m \033[4munderlined\033[0m',
            foo, '')

    def test_multiple(self):
        def foo():
            """summary-of-foo

            Implements FOO.
            """

        def bar():
            """summary-of-bar

            Implements BAR."""

        self.assert_in_help('summary-of-foo', [foo, bar], '')
        self.assert_not_in_help('FOO', [foo, bar], '')

    def assert_in_help(self, s, funcs, flags):
        self.assertIn(s, self._get_help(funcs, flags))

    def assert_not_in_help(self, s, funcs, flags):
        self.assertNotIn(s, self._get_help(funcs, flags))

    def _get_help(self, funcs, flags):
        self.assertLessEqual({*flags}, {'d', 't', 'n'})
        parser = defopt._create_parser(funcs, _options(
            show_defaults='d' in flags, show_types='t' in flags,
            no_negated_flags='n' in flags, cli_options='has_default'))
        return parser.format_help()


@contextlib.contextmanager
def _assert_streams(self, *, stdout=None, stderr=None):
    with ExitStack() as stack:
        if stdout is not None:
            r_stdout = stack.enter_context(
                contextlib.redirect_stdout(StringIO()))
            stack.callback(
                lambda: self.assertRegex(r_stdout.getvalue(), stdout))
        if stderr is not None:
            r_stderr = stack.enter_context(
                contextlib.redirect_stderr(StringIO()))
            stack.callback(
                lambda: self.assertRegex(r_stderr.getvalue(), stderr))
        yield


class TestErrorMessage(unittest.TestCase):
    def test_enum(self):
        def foo(x: Choice): pass
        with self.assertRaises(SystemExit), _assert_streams(
                self, stderr="error: argument x: invalid choice: 'three'"):
            defopt.run(foo, argv=['three'])

    def test_literal(self):
        def foo(x: defopt.Literal[1, "a"]): pass
        with self.assertRaises(SystemExit), _assert_streams(
                self, stderr="error: argument x: invalid choice: 'three'"):
            defopt.run(foo, argv=['three'])

    def test_tuple(self):
        def foo(x: typing.Tuple[int]): pass
        with self.assertRaises(SystemExit), _assert_streams(
                self, stderr="error: argument x: invalid literal for int"):
            defopt.run(foo, argv=['three'])


class TestVersion(unittest.TestCase):
    def test_no_version(self):
        for funcs in [[], lambda: None, [lambda: None]]:
            with self.assertRaises(SystemExit), _assert_streams(
                     self,
                     stdout=r'\A\Z',
                     stderr='unrecognized arguments: --version'):
                defopt.run([], version=False, argv=['--version'])

    def test_auto_version(self):
        with self.assertRaises(SystemExit), _assert_streams(
                 self, stdout=rf'\A{re.escape(__version__)}\n\Z'):
            defopt.run(lambda: None, argv=['--version'])
        with self.assertRaises(SystemExit), _assert_streams(
                 self,
                 stdout=r'\A\Z',
                 stderr='unrecognized arguments: --version'):
            defopt.run([], argv=['--version'])

    def test_manual_version(self):
        with self.assertRaises(SystemExit), _assert_streams(
                self, stdout=r'\Afoo 42\n\Z'):
            defopt.run([], version='foo 42', argv=['--version'])

    def test_moduleless(self):
        def moduleless(): pass
        moduleless.__module__ = None
        with self.assertRaises(ValueError):
            defopt.run([moduleless], version=True)


class TestExamples(unittest.TestCase):
    def test_annotations(self):
        for command in [annotations.documented, annotations.undocumented]:
            with self._assert_stdout('[1, 8]\n'):
                command([1, 2], 3)

    def test_annotations_cli(self):
        for command in ['documented', 'undocumented']:
            args = [command, '--numbers', '1', '2', '--', '3']
            output = self._run_example(annotations, args)
            self.assertEqual(output, b'[1.0, 8.0]\n')

    def test_booleans(self):
        with self._assert_stdout('test\ntest\n'):
            booleans.main('test', upper=False, repeat=True)
        with self._assert_stdout('TEST\n'):
            booleans.main('test')

    def test_booleans_cli(self):
        output = self._run_example(
            booleans, ['test', '--no-upper', '--repeat'])
        self.assertEqual(output, b'test\ntest\n')
        output = self._run_example(
            booleans, ['test'])
        self.assertEqual(output, b'TEST\n')

    def test_choices(self):
        with self._assert_stdout('Choice.one (1)\n'):
            choices.choose_enum(choices.Choice.one)
        with self._assert_stdout('Choice.one (1)\nChoice.two (2.0)\n'):
            choices.choose_enum(choices.Choice.one, opt=choices.Choice.two)
        with self.assertRaises(AttributeError):
            choices.choose_enum('one')
        with self._assert_stdout('foo\n'):
            choices.choose_literal('foo')
        with self._assert_stdout('foo\nbaz\n'):
            choices.choose_literal('foo', opt='baz')

    def test_choices_cli(self):
        output = self._run_example(choices, ['choose-enum', 'one'])
        self.assertEqual(output, b'Choice.one (1)\n')
        output = self._run_example(
            choices, ['choose-enum', 'one', '--opt', 'two'])
        self.assertEqual(output, b'Choice.one (1)\nChoice.two (2.0)\n')
        with self.assertRaises(subprocess.CalledProcessError) as error:
            self._run_example(choices, ['choose-enum', 'four'])
        self.assertIn(b'four', error.exception.output)
        self.assertIn(b'{one,two,three}', error.exception.output)
        output = self._run_example(choices, ['choose-literal', 'foo'])
        self.assertEqual(output, b'foo\n')
        output = self._run_example(
            choices, ['choose-literal', 'foo', '--opt', 'baz'])
        self.assertEqual(output, b'foo\nbaz\n')
        with self.assertRaises(subprocess.CalledProcessError) as error:
            self._run_example(choices, ['choose-literal', 'baz'])
        self.assertIn(b'baz', error.exception.output)
        self.assertIn(b'{foo,bar}', error.exception.output)

    def test_exceptions(self):
        self._run_example(exceptions, ['1'])
        with self.assertRaises(subprocess.CalledProcessError) as error:
            self._run_example(exceptions, ['0'])
        self.assertIn(b"Don't do this!", error.exception.output)
        self.assertNotIn(b"Traceback", error.exception.output)

    def test_lists(self):
        with self._assert_stdout('[2.4, 6.8]\n'):
            lists.main([1.2, 3.4], 2)
        with self._assert_stdout('[2, 4, 6]\n'):
            lists.main([1, 2, 3], 2)

    def test_lists_cli(self):
        output = self._run_example(
            lists, ['2', '--numbers', '1.2', '3.4'])
        self.assertEqual(output, b'[2.4, 6.8]\n')
        output = self._run_example(
            lists, ['--numbers', '1.2', '3.4', '--', '2'])
        self.assertEqual(output, b'[2.4, 6.8]\n')

    def test_parsers(self):
        date = parsers.datetime(2015, 9, 13)
        with self._assert_stdout(f'{date}\n'):
            parsers.main(date)
        with self._assert_stdout('junk\n'):
            parsers.main('junk')

    def test_parsers_cli(self):
        output = self._run_example(parsers, ['2015-09-13'])
        self.assertEqual(output, b'2015-09-13 00:00:00\n')
        with self.assertRaises(subprocess.CalledProcessError) as error:
            self._run_example(parsers, ['junk'])
        self.assertIn(b'datetime', error.exception.output)
        self.assertIn(b'junk', error.exception.output)

    def test_short(self):
        with self._assert_stdout('hello!\n'):
            short.main()
        with self._assert_stdout('hello!\nhello!\n'):
            short.main(count=2)

    def test_short_cli(self):
        output = self._run_example(short, ['--count', '2'])
        self.assertEqual(output, b'hello!\nhello!\n')
        output = self._run_example(short, ['-C', '2'])
        self.assertEqual(output, b'hello!\nhello!\n')

    def test_starargs(self):
        with self._assert_stdout('1\n2\n3\n'):
            starargs.plain(1, 2, 3)
        with self._assert_stdout('[1, 2]\n[3, 4, 5]\n'):
            starargs.iterable([1, 2], [3, 4, 5])

    def test_starargs_cli(self):
        output = self._run_example(starargs, ['plain', '1', '2', '3'])
        self.assertEqual(output, b'1\n2\n3\n')
        args = ['iterable', '--groups', '1', '2', '--groups', '3', '4', '5']
        output = self._run_example(starargs, args)
        self.assertEqual(output, b'[1, 2]\n[3, 4, 5]\n')

    def test_styles(self):
        for command in [styles.sphinx, styles.google, styles.numpy]:
            with self._assert_stdout('4\n'):
                command(2)
            with self._assert_stdout('4\nbye\n'):
                command(2, farewell='bye')

    def test_styles_cli(self):
        for style in ['sphinx', 'google', 'numpy']:
            args = [style, '2', '--farewell', 'bye']
            output = self._run_example(styles, args)
            self.assertEqual(output, b'4\nbye\n')

    @contextlib.contextmanager
    def _assert_stdout(self, s):
        with contextlib.redirect_stdout(StringIO()) as file:
            yield
            self.assertEqual(file.getvalue(), s)

    def _run_example(self, example, argv):
        output = subprocess.check_output(
            [sys.executable, '-m', example.__name__] + argv,
            stderr=subprocess.STDOUT)
        return output.replace(b'\r\n', b'\n')


class TestRunAny(unittest.TestCase):  # TODO: Reuse TestExamples.
    def test_lists_cli(self):
        output = self._run_any(
            'examples.lists.main', ['2', '--numbers', '1.2', '3.4'])
        self.assertEqual(output, '[2.4, 6.8]\n')
        output = self._run_any(
            'examples.lists:main', ['--numbers', '1.2', '3.4', '--', '2'])
        self.assertEqual(output, '[2.4, 6.8]\n')

    def test_failed_imports(self):
        with self.assertRaises((ImportError, subprocess.CalledProcessError)):
            self._run_any('does_not_exist', [])

    @staticmethod
    def _target(command, argv):
        sys.argv[1:] = [command, *argv]  # Only executed in a subprocess.
        buf = StringIO()
        with contextlib.redirect_stdout(buf), contextlib.redirect_stderr(buf):
            runpy.run_module('defopt', run_name='__main__', alter_sys=True)
        return buf.getvalue()

    def _run_any(self, command, argv, **kwargs):
        if sys.version_info >= (3, 7):  # multiprocessing for proper coverage.
            with ProcessPoolExecutor(mp_context=mp.get_context('spawn')) \
                    as executor:
                fut = executor.submit(self._target, command, argv)
            return fut.result().replace('\r\n', '\n')
        else:  # mp_context is not available.
            output = subprocess.check_output(
                [sys.executable, '-m', 'defopt', command] + argv,
                stderr=subprocess.STDOUT, universal_newlines=True, **kwargs)
            return output.replace('\r\n', '\n')


class TestDefaultsPreserved(unittest.TestCase):
    def test_defaults_preserved(self):
        """Check that mutable defaults are not modified."""
        params = inspect.signature(defopt.run).parameters
        self.assertEqual(params['parsers'].default, {})
        self.assertEqual(params['argparse_kwargs'].default, {})


class TestStyle(unittest.TestCase):
    def _iter_stripped_lines(self):
        for path in [defopt.__file__, __file__]:
            with tokenize.open(path) as src:
                for i, line in enumerate(src, 1):
                    yield f'{path}:{i}', line.rstrip('\n')

    def test_line_length(self):
        for name, line in self._iter_stripped_lines():
            if len(line) > 79:
                self.fail(f'{name} is too long')

    def test_trailing_whitespace(self):
        for name, line in self._iter_stripped_lines():
            if line and line[-1].isspace():
                self.fail(f'{name} has trailing whitespace')