Closes #12713: Allowed abbreviation of subcommands in argparse.
diff --git a/Lib/argparse.py b/Lib/argparse.py
index 209b4e9..e0edad8 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -1110,6 +1110,12 @@
parser_name = values[0]
arg_strings = values[1:]
+ # get full parser_name from (optional) abbreviated one
+ for p in self._name_parser_map:
+ if p.startswith(parser_name):
+ parser_name = p
+ break
+
# set the parser name if requested
if self.dest is not SUPPRESS:
setattr(namespace, self.dest, parser_name)
@@ -2307,11 +2313,18 @@
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)
+ if action.choices is not None:
+ ac = [ax for ax in action.choices if str(ax).startswith(str(value))]
+ if len(ac) == 0:
+ args = {'value': value,
+ 'choices': ', '.join(map(repr, action.choices))}
+ msg = _('invalid choice: %(value)r (choose from %(choices)s)')
+ raise ArgumentError(action, msg % args)
+ elif len(ac) > 1:
+ args = {'value': value,
+ 'choices': ', '.join(ac)}
+ msg = _('ambiguous choice: %(value)r could match %(choices)s')
+ raise ArgumentError(action, msg % args)
# =======================
# Help-formatting methods