Issue #14910: Add allow_abbrev parameter to argparse.ArgumentParser.
Patch by Jonathan Paugh, Steven Bethard, paul j3 and Daniel Eriksson.
diff --git a/Lib/argparse.py b/Lib/argparse.py
index ba9e3df..9a06719 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -1590,6 +1590,7 @@
- argument_default -- The default value for all arguments
- conflict_handler -- String indicating how to handle conflicts
- add_help -- Add a -h/-help option
+ - allow_abbrev -- Allow long options to be abbreviated unambiguously
"""
def __init__(self,
@@ -1603,7 +1604,8 @@
fromfile_prefix_chars=None,
argument_default=None,
conflict_handler='error',
- add_help=True):
+ add_help=True,
+ allow_abbrev=True):
superinit = super(ArgumentParser, self).__init__
superinit(description=description,
@@ -1621,6 +1623,7 @@
self.formatter_class = formatter_class
self.fromfile_prefix_chars = fromfile_prefix_chars
self.add_help = add_help
+ self.allow_abbrev = allow_abbrev
add_group = self.add_argument_group
self._positionals = add_group(_('positional arguments'))
@@ -2098,23 +2101,24 @@
action = self._option_string_actions[option_string]
return action, option_string, explicit_arg
- # search through all possible prefixes of the option string
- # and all actions in the parser for possible interpretations
- option_tuples = self._get_option_tuples(arg_string)
+ if self.allow_abbrev:
+ # search through all possible prefixes of the option string
+ # and all actions in the parser for possible interpretations
+ option_tuples = self._get_option_tuples(arg_string)
- # if multiple actions match, the option string was ambiguous
- if len(option_tuples) > 1:
- options = ', '.join([option_string
- for action, option_string, explicit_arg in option_tuples])
- args = {'option': arg_string, 'matches': options}
- msg = _('ambiguous option: %(option)s could match %(matches)s')
- self.error(msg % args)
+ # if multiple actions match, the option string was ambiguous
+ if len(option_tuples) > 1:
+ options = ', '.join([option_string
+ for action, option_string, explicit_arg in option_tuples])
+ args = {'option': arg_string, 'matches': options}
+ msg = _('ambiguous option: %(option)s could match %(matches)s')
+ self.error(msg % args)
- # if exactly one action matched, this segmentation is good,
- # so return the parsed action
- elif len(option_tuples) == 1:
- option_tuple, = option_tuples
- return option_tuple
+ # if exactly one action matched, this segmentation is good,
+ # so return the parsed action
+ elif len(option_tuples) == 1:
+ option_tuple, = option_tuples
+ return option_tuple
# if it was not found as an option, but it looks like a negative
# number, it was meant to be positional
diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py
index a0b9162..d7f90cd 100644
--- a/Lib/test/test_argparse.py
+++ b/Lib/test/test_argparse.py
@@ -753,6 +753,39 @@
]
+class TestOptionalsAllowLongAbbreviation(ParserTestCase):
+ """Allow long options to be abbreviated unambiguously"""
+
+ argument_signatures = [
+ Sig('--foo'),
+ Sig('--foobaz'),
+ Sig('--fooble', action='store_true'),
+ ]
+ failures = ['--foob 5', '--foob']
+ successes = [
+ ('', NS(foo=None, foobaz=None, fooble=False)),
+ ('--foo 7', NS(foo='7', foobaz=None, fooble=False)),
+ ('--fooba a', NS(foo=None, foobaz='a', fooble=False)),
+ ('--foobl --foo g', NS(foo='g', foobaz=None, fooble=True)),
+ ]
+
+
+class TestOptionalsDisallowLongAbbreviation(ParserTestCase):
+ """Do not allow abbreviations of long options at all"""
+
+ parser_signature = Sig(allow_abbrev=False)
+ argument_signatures = [
+ Sig('--foo'),
+ Sig('--foodle', action='store_true'),
+ Sig('--foonly'),
+ ]
+ failures = ['-foon 3', '--foon 3', '--food', '--food --foo 2']
+ successes = [
+ ('', NS(foo=None, foodle=False, foonly=None)),
+ ('--foo 3', NS(foo='3', foodle=False, foonly=None)),
+ ('--foonly 7 --foodle --foo 2', NS(foo='2', foodle=True, foonly='7')),
+ ]
+
# ================
# Positional tests
# ================