From 0cb4d6c6549d2299f7518f083bbe7d10314ecd66 Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Fri, 22 Nov 2024 17:29:33 +0200 Subject: [PATCH] gh-86463: Fix default prog in subparsers if usage is used in the main parser (GH-125891) The usage parameter of argparse.ArgumentParser no longer affects the default value of the prog parameter in subparsers. Previously the full custom usage of the main parser was used as the prog prefix in subparsers. --- Doc/library/argparse.rst | 10 ++++ Lib/argparse.py | 2 +- Lib/test/test_argparse.py | 51 +++++++++++++++++-- ...4-10-23-20-05-54.gh-issue-86463.jvFTI_.rst | 2 + 4 files changed, 60 insertions(+), 5 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2024-10-23-20-05-54.gh-issue-86463.jvFTI_.rst diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst index a4695547921..c5882c27371 100644 --- a/Doc/library/argparse.rst +++ b/Doc/library/argparse.rst @@ -192,6 +192,12 @@ arguments it contains. The default message can be overridden with the The ``%(prog)s`` format specifier is available to fill in the program name in your usage messages. +When a custom usage message is specified for the main parser, you may also want to +consider passing the ``prog`` argument to :meth:`~ArgumentParser.add_subparsers` +or the ``prog`` and the ``usage`` arguments to +:meth:`~_SubParsersAction.add_parser`, to ensure consistent command prefixes and +usage information across subparsers. + .. _description: @@ -1810,6 +1816,10 @@ Sub-commands .. versionchanged:: 3.7 New *required* keyword-only parameter. + .. versionchanged:: 3.14 + Subparser's *prog* is no longer affected by a custom usage message in + the main parser. + FileType objects ^^^^^^^^^^^^^^^^ diff --git a/Lib/argparse.py b/Lib/argparse.py index 5ecfdca1717..f5a7342c2fc 100644 --- a/Lib/argparse.py +++ b/Lib/argparse.py @@ -1889,7 +1889,7 @@ def add_subparsers(self, **kwargs): formatter = self._get_formatter() positionals = self._get_positional_actions() groups = self._mutually_exclusive_groups - formatter.add_usage(self.usage, positionals, groups, '') + formatter.add_usage(None, positionals, groups, '') kwargs['prog'] = formatter.format_help().strip() # create the parsers action and add it to the positionals list diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py index 358cfb1c56a..69243fde5f0 100644 --- a/Lib/test/test_argparse.py +++ b/Lib/test/test_argparse.py @@ -2409,16 +2409,17 @@ def assertArgumentParserError(self, *args, **kwargs): self.assertRaises(ArgumentParserError, *args, **kwargs) def _get_parser(self, subparser_help=False, prefix_chars=None, - aliases=False): + aliases=False, usage=None): # create a parser with a subparsers argument if prefix_chars: parser = ErrorRaisingArgumentParser( - prog='PROG', description='main description', prefix_chars=prefix_chars) + prog='PROG', description='main description', usage=usage, + prefix_chars=prefix_chars) parser.add_argument( prefix_chars[0] * 2 + 'foo', action='store_true', help='foo help') else: parser = ErrorRaisingArgumentParser( - prog='PROG', description='main description') + prog='PROG', description='main description', usage=usage) parser.add_argument( '--foo', action='store_true', help='foo help') parser.add_argument( @@ -2455,7 +2456,8 @@ def _get_parser(self, subparser_help=False, prefix_chars=None, parser2.add_argument('z', type=complex, nargs='*', help='z help') # add third sub-parser - parser3_kwargs = dict(description='3 description') + parser3_kwargs = dict(description='3 description', + usage='PROG --foo bar 3 t ...') if subparser_help: parser3_kwargs['help'] = '3 help' parser3 = subparsers.add_parser('3', **parser3_kwargs) @@ -2477,6 +2479,47 @@ def test_parse_args_failures(self): args = args_str.split() self.assertArgumentParserError(self.parser.parse_args, args) + def test_parse_args_failures_details(self): + for args_str, usage_str, error_str in [ + ('', + 'usage: PROG [-h] [--foo] bar {1,2,3} ...', + 'PROG: error: the following arguments are required: bar'), + ('0.5 1 -y', + 'usage: PROG bar 1 [-h] [-w W] {a,b,c}', + 'PROG bar 1: error: the following arguments are required: x'), + ('0.5 3', + 'usage: PROG --foo bar 3 t ...', + 'PROG bar 3: error: the following arguments are required: t'), + ]: + with self.subTest(args_str): + args = args_str.split() + with self.assertRaises(ArgumentParserError) as cm: + self.parser.parse_args(args) + self.assertEqual(cm.exception.args[0], 'SystemExit') + self.assertEqual(cm.exception.args[2], f'{usage_str}\n{error_str}\n') + + def test_parse_args_failures_details_custom_usage(self): + parser = self._get_parser(usage='PROG [--foo] bar 1 [-w W] {a,b,c}\n' + ' PROG --foo bar 3 t ...') + for args_str, usage_str, error_str in [ + ('', + 'usage: PROG [--foo] bar 1 [-w W] {a,b,c}\n' + ' PROG --foo bar 3 t ...', + 'PROG: error: the following arguments are required: bar'), + ('0.5 1 -y', + 'usage: PROG bar 1 [-h] [-w W] {a,b,c}', + 'PROG bar 1: error: the following arguments are required: x'), + ('0.5 3', + 'usage: PROG --foo bar 3 t ...', + 'PROG bar 3: error: the following arguments are required: t'), + ]: + with self.subTest(args_str): + args = args_str.split() + with self.assertRaises(ArgumentParserError) as cm: + parser.parse_args(args) + self.assertEqual(cm.exception.args[0], 'SystemExit') + self.assertEqual(cm.exception.args[2], f'{usage_str}\n{error_str}\n') + def test_parse_args(self): # check some non-failure cases: self.assertEqual( diff --git a/Misc/NEWS.d/next/Library/2024-10-23-20-05-54.gh-issue-86463.jvFTI_.rst b/Misc/NEWS.d/next/Library/2024-10-23-20-05-54.gh-issue-86463.jvFTI_.rst new file mode 100644 index 00000000000..9ac155770e2 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-10-23-20-05-54.gh-issue-86463.jvFTI_.rst @@ -0,0 +1,2 @@ +The ``usage`` parameter of :class:`argparse.ArgumentParser` no longer +affects the default value of the ``prog`` parameter in subparsers.