[3.12] gh-125355: Rewrite parse_intermixed_args() in argparse (GH-125356) (GH-125839)

* The parser no longer changes temporarily during parsing.
* Default values are not processed twice.
* Required mutually exclusive groups containing positional arguments are
  now supported.
* The missing arguments report now includes the names of all required
  optional and positional arguments.
* Unknown options can be intermixed with positional arguments in
  parse_known_intermixed_args().

(cherry picked from commit 759a54d28f)
This commit is contained in:
Serhiy Storchaka 2024-10-22 16:23:30 +03:00 committed by GitHub
parent 98a0b362b5
commit da3d81d3ea
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GPG key ID: B5690EEEBB952194
3 changed files with 81 additions and 77 deletions

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@ -1911,6 +1911,9 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
return args
def parse_known_args(self, args=None, namespace=None):
return self._parse_known_args2(args, namespace, intermixed=False)
def _parse_known_args2(self, args, namespace, intermixed):
if args is None:
# args default to the system args
args = _sys.argv[1:]
@ -1937,18 +1940,18 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
# parse the arguments and exit if there are any errors
if self.exit_on_error:
try:
namespace, args = self._parse_known_args(args, namespace)
namespace, args = self._parse_known_args(args, namespace, intermixed)
except ArgumentError as err:
self.error(str(err))
else:
namespace, args = self._parse_known_args(args, namespace)
namespace, args = self._parse_known_args(args, namespace, intermixed)
if hasattr(namespace, _UNRECOGNIZED_ARGS_ATTR):
args.extend(getattr(namespace, _UNRECOGNIZED_ARGS_ATTR))
delattr(namespace, _UNRECOGNIZED_ARGS_ATTR)
return namespace, args
def _parse_known_args(self, arg_strings, namespace):
def _parse_known_args(self, arg_strings, namespace, intermixed):
# replace arg strings that are file references
if self.fromfile_prefix_chars is not None:
arg_strings = self._read_args_from_files(arg_strings)
@ -2038,6 +2041,7 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
# if we found no optional action, skip it
if action is None:
extras.append(arg_strings[start_index])
extras_pattern.append('O')
return start_index + 1
# if there is an explicit argument, try to match the
@ -2073,6 +2077,7 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
sep = ''
else:
extras.append(char + explicit_arg)
extras_pattern.append('O')
stop = start_index + 1
break
# if the action expect exactly one argument, we've
@ -2143,6 +2148,7 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
# consume Positionals and Optionals alternately, until we have
# passed the last option string
extras = []
extras_pattern = []
start_index = 0
if option_string_indices:
max_option_string_index = max(option_string_indices)
@ -2155,7 +2161,7 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
index
for index in option_string_indices
if index >= start_index])
if start_index != next_option_string_index:
if not intermixed and start_index != next_option_string_index:
positionals_end_index = consume_positionals(start_index)
# only try to parse the next optional if we didn't consume
@ -2171,16 +2177,35 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
if start_index not in option_string_indices:
strings = arg_strings[start_index:next_option_string_index]
extras.extend(strings)
extras_pattern.extend(arg_strings_pattern[start_index:next_option_string_index])
start_index = next_option_string_index
# consume the next optional and any arguments for it
start_index = consume_optional(start_index)
# consume any positionals following the last Optional
stop_index = consume_positionals(start_index)
if not intermixed:
# consume any positionals following the last Optional
stop_index = consume_positionals(start_index)
# if we didn't consume all the argument strings, there were extras
extras.extend(arg_strings[stop_index:])
# if we didn't consume all the argument strings, there were extras
extras.extend(arg_strings[stop_index:])
else:
extras.extend(arg_strings[start_index:])
extras_pattern.extend(arg_strings_pattern[start_index:])
extras_pattern = ''.join(extras_pattern)
assert len(extras_pattern) == len(extras)
# consume all positionals
arg_strings = [s for s, c in zip(extras, extras_pattern) if c != 'O']
arg_strings_pattern = extras_pattern.replace('O', '')
stop_index = consume_positionals(0)
# leave unknown optionals and non-consumed positionals in extras
for i, c in enumerate(extras_pattern):
if not stop_index:
break
if c != 'O':
stop_index -= 1
extras[i] = None
extras = [s for s in extras if s is not None]
# make sure all required actions were present and also convert
# action defaults which were not given as arguments
@ -2446,10 +2471,6 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
# are then parsed. If the parser definition is incompatible with the
# intermixed assumptions (e.g. use of REMAINDER, subparsers) a
# TypeError is raised.
#
# positionals are 'deactivated' by setting nargs and default to
# SUPPRESS. This blocks the addition of that positional to the
# namespace
positionals = self._get_positional_actions()
a = [action for action in positionals
@ -2458,59 +2479,7 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer):
raise TypeError('parse_intermixed_args: positional arg'
' with nargs=%s'%a[0].nargs)
if [action.dest for group in self._mutually_exclusive_groups
for action in group._group_actions if action in positionals]:
raise TypeError('parse_intermixed_args: positional in'
' mutuallyExclusiveGroup')
try:
save_usage = self.usage
try:
if self.usage is None:
# capture the full usage for use in error messages
self.usage = self.format_usage()[7:]
for action in positionals:
# deactivate positionals
action.save_nargs = action.nargs
# action.nargs = 0
action.nargs = SUPPRESS
action.save_default = action.default
action.default = SUPPRESS
namespace, remaining_args = self.parse_known_args(args,
namespace)
for action in positionals:
# remove the empty positional values from namespace
if (hasattr(namespace, action.dest)
and getattr(namespace, action.dest)==[]):
from warnings import warn
warn('Do not expect %s in %s' % (action.dest, namespace))
delattr(namespace, action.dest)
finally:
# restore nargs and usage before exiting
for action in positionals:
action.nargs = action.save_nargs
action.default = action.save_default
optionals = self._get_optional_actions()
try:
# parse positionals. optionals aren't normally required, but
# they could be, so make sure they aren't.
for action in optionals:
action.save_required = action.required
action.required = False
for group in self._mutually_exclusive_groups:
group.save_required = group.required
group.required = False
namespace, extras = self.parse_known_args(remaining_args,
namespace)
finally:
# restore parser values before exiting
for action in optionals:
action.required = action.save_required
for group in self._mutually_exclusive_groups:
group.required = group.save_required
finally:
self.usage = save_usage
return namespace, extras
return self._parse_known_args2(args, namespace, intermixed=True)
# ========================
# Value conversion methods