[3.13] gh-61181: Fix support of choices with string value in argparse (GH-124578) (GH-124755)
Substrings of the specified string no longer considered valid values.
(cherry picked from commit f1a2417b9e2993e584610851ac004c8b0599b323)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst
index 53ecc97..95ee757 100644
--- a/Doc/library/argparse.rst
+++ b/Doc/library/argparse.rst
@@ -1804,7 +1804,7 @@
>>>
>>> # create the parser for the "b" command
>>> parser_b = subparsers.add_parser('b', help='b help')
- >>> parser_b.add_argument('--baz', choices='XYZ', help='baz help')
+ >>> parser_b.add_argument('--baz', choices=('X', 'Y', 'Z'), help='baz help')
>>>
>>> # parse some argument lists
>>> parser.parse_args(['a', '12'])
diff --git a/Lib/argparse.py b/Lib/argparse.py
index 5d6a065..926907a 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -2582,11 +2582,15 @@ def _get_value(self, action, arg_string):
def _check_value(self, action, value):
# converted value must be one of the choices (if specified)
- if action.choices is not None and value not in action.choices:
- args = {'value': value,
- 'choices': ', '.join(map(repr, action.choices))}
- msg = _('invalid choice: %(value)r (choose from %(choices)s)')
- raise ArgumentError(action, msg % args)
+ choices = action.choices
+ if choices is not None:
+ if isinstance(choices, str):
+ choices = iter(choices)
+ if value not in choices:
+ args = {'value': value,
+ 'choices': ', '.join(map(repr, action.choices))}
+ msg = _('invalid choice: %(value)r (choose from %(choices)s)')
+ raise ArgumentError(action, msg % args)
# =======================
# Help-formatting methods
diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py
index 7a55dc2..fe71e8a 100644
--- a/Lib/test/test_argparse.py
+++ b/Lib/test/test_argparse.py
@@ -686,7 +686,7 @@ class TestOptionalsChoices(ParserTestCase):
argument_signatures = [
Sig('-f', choices='abc'),
Sig('-g', type=int, choices=range(5))]
- failures = ['a', '-f d', '-fad', '-ga', '-g 6']
+ failures = ['a', '-f d', '-f ab', '-fad', '-ga', '-g 6']
successes = [
('', NS(f=None, g=None)),
('-f a', NS(f='a', g=None)),
@@ -2291,14 +2291,14 @@ def _get_parser(self, subparser_help=False, prefix_chars=None,
parser1_kwargs['aliases'] = ['1alias1', '1alias2']
parser1 = subparsers.add_parser('1', **parser1_kwargs)
parser1.add_argument('-w', type=int, help='w help')
- parser1.add_argument('x', choices='abc', help='x help')
+ parser1.add_argument('x', choices=['a', 'b', 'c'], help='x help')
# add second sub-parser
parser2_kwargs = dict(description='2 description')
if subparser_help:
parser2_kwargs['help'] = '2 help'
parser2 = subparsers.add_parser('2', **parser2_kwargs)
- parser2.add_argument('-y', choices='123', help='y help')
+ parser2.add_argument('-y', choices=['1', '2', '3'], help='y help')
parser2.add_argument('z', type=complex, nargs='*', help='z help')
# add third sub-parser
@@ -4628,7 +4628,7 @@ class TestHelpVariableExpansion(HelpTestCase):
help='x %(prog)s %(default)s %(type)s %%'),
Sig('-y', action='store_const', default=42, const='XXX',
help='y %(prog)s %(default)s %(const)s'),
- Sig('--foo', choices='abc',
+ Sig('--foo', choices=['a', 'b', 'c'],
help='foo %(prog)s %(default)s %(choices)s'),
Sig('--bar', default='baz', choices=[1, 2], metavar='BBB',
help='bar %(prog)s %(default)s %(dest)s'),
@@ -5291,7 +5291,7 @@ def test_no_argument_actions(self):
for action in ['store_const', 'store_true', 'store_false',
'append_const', 'count']:
for attrs in [dict(type=int), dict(nargs='+'),
- dict(choices='ab')]:
+ dict(choices=['a', 'b'])]:
self.assertTypeError('-x', action=action, **attrs)
def test_no_argument_no_const_actions(self):
diff --git a/Misc/NEWS.d/next/Library/2024-09-26-09-18-09.gh-issue-61181.dwjmch.rst b/Misc/NEWS.d/next/Library/2024-09-26-09-18-09.gh-issue-61181.dwjmch.rst
new file mode 100644
index 0000000..801a5fd
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2024-09-26-09-18-09.gh-issue-61181.dwjmch.rst
@@ -0,0 +1,2 @@
+Fix support of :ref:`choices` with string value in :mod:`argparse`. Substrings
+of the specified string no longer considered valid values.
