chore: Pull value-consumingness into ArgAction method.

src/cappa/arg.py

@@ -56,6 +56,16 @@ def value_actions(cls) -> typing.Set[ArgAction]:
  def is_custom(cls, action: ArgAction | Callable | None):
  return action is not None and not isinstance(action, ArgAction)
 
+ @classmethod
+ def is_non_value_consuming(cls, action: ArgAction | Callable | None):
+ return action in {
+ ArgAction.store_true,
+ ArgAction.store_false,
+ ArgAction.count,
+ ArgAction.version,
+ ArgAction.help,
+ }
+
  @property
  def is_bool_action(self):
  return self in {self.store_true, self.store_false}
@@ -150,7 +160,7 @@ def collect(
  default_short: bool = False,
  default_long: bool = False,
  ) -> list[Arg]:
- args = find_annotations(type_view, cls) or [DEFAULT_ARG]
+ args = find_annotations(type_view, cls) or [Arg()]
 
  exclusive = len(args) > 1
 
@@ -457,7 +467,7 @@ def infer_num_args(
  if arg.parse:
  return 1
 
- if isinstance(action, ArgAction) and action in no_extra_arg_actions:
+ if ArgAction.is_non_value_consuming(action):
  return 0
 
  if type_view.is_union:
@@ -597,14 +607,3 @@ def explode_negated_bool_args(args: typing.Sequence[Arg]) -> typing.Iterable[Arg
 
  if not yielded:
  yield arg
-
-
-no_extra_arg_actions = {
- ArgAction.store_true,
- ArgAction.store_false,
- ArgAction.count,
- ArgAction.version,
- ArgAction.help,
-}
-
-DEFAULT_ARG: Arg = Arg()

src/cappa/argparse.py

@@ -5,7 +5,7 @@
 import typing
 from collections.abc import Callable
 
-from cappa.arg import Arg, ArgAction, no_extra_arg_actions
+from cappa.arg import Arg, ArgAction
 from cappa.command import Command, Subcommand
 from cappa.help import generate_arg_groups
 from cappa.invoke import fulfill_deps
@@ -242,7 +242,7 @@ def add_argument(
  if arg.default is not Empty:
  kwargs["default"] = argparse.SUPPRESS
 
- if num_args is not None and (arg.action and arg.action not in no_extra_arg_actions):
+ if num_args is not None and not ArgAction.is_non_value_consuming(arg.action):
  kwargs["nargs"] = num_args
  elif is_positional and not arg.required:
  kwargs["nargs"] = "?"

src/cappa/help.py

@@ -12,7 +12,7 @@
 from rich.text import Text
 from typing_extensions import Self, TypeAlias
 
-from cappa.arg import Arg, ArgAction, Group, no_extra_arg_actions
+from cappa.arg import Arg, ArgAction, Group
 from cappa.output import Displayable
 from cappa.subcommand import Subcommand
 from cappa.type_view import Empty
@@ -220,7 +220,7 @@ def add_short_args(prog: str, arg_groups: list[ArgGroup]) -> str:
 def format_arg_name(arg: Arg | Subcommand, delimiter, *, n=0) -> str:
  if isinstance(arg, Arg):
  is_option = arg.short or arg.long
- has_value = arg.action not in no_extra_arg_actions
+ has_value = not ArgAction.is_non_value_consuming(arg.action)
 
  arg_names = arg.names_str(delimiter, n=n)
  if not is_option:

src/cappa/parser.py

@@ -4,7 +4,7 @@
 import typing
 from collections import deque
 
-from cappa.arg import Arg, ArgAction, Group, no_extra_arg_actions
+from cappa.arg import Arg, ArgAction, Group
 from cappa.command import Command, Subcommand
 from cappa.completion.types import Completion, FileCompletion
 from cappa.help import format_subcommand_names
@@ -478,7 +478,7 @@ def consume_arg(
  orig_num_args = arg.num_args if arg.num_args is not None else 1
  num_args = orig_num_args
 
- if arg.action in no_extra_arg_actions:
+ if ArgAction.is_non_value_consuming(arg.action):
  orig_num_args = 0
  num_args = 0