Method _build_parser

cmd2/cmd2.py:913–947

Build argument parser for a command/subcommand. :param parent: object which owns the command using the parser. When parser_builder is a classmethod, this function passes parent's class to it. :param parser_builder: an existing Cmd2Argume

(
        self,
        parent: CmdOrSet,
        parser_builder: Cmd2ArgumentParser | Callable[[], Cmd2ArgumentParser] | StaticArgParseBuilder | ClassArgParseBuilder,
    )

            raise

    def _build_parser(
        self,
        parent: CmdOrSet,
        parser_builder: Cmd2ArgumentParser | Callable[[], Cmd2ArgumentParser] | StaticArgParseBuilder | ClassArgParseBuilder,
    ) -> Cmd2ArgumentParser:
        """Build argument parser for a command/subcommand.

        :param parent: object which owns the command using the parser.
                       When parser_builder is a classmethod, this function passes
                       parent's class to it.
        :param parser_builder: an existing Cmd2ArgumentParser instance or a factory
                               (callable, staticmethod, or classmethod) that returns one.
        :return: new parser
        :raises TypeError: if parser_builder is an invalid type or if the factory fails
                           to return a Cmd2ArgumentParser
        """
        if isinstance(parser_builder, Cmd2ArgumentParser):
            parser = copy.deepcopy(parser_builder)
        else:
            # Try to build the parser with a factory
            if isinstance(parser_builder, staticmethod):
                parser = parser_builder.__func__()
            elif isinstance(parser_builder, classmethod):
                parser = parser_builder.__func__(parent.__class__)
            elif callable(parser_builder):
                parser = parser_builder()
            else:
                raise TypeError(f"Invalid type for parser_builder: {type(parser_builder)}")

            # Verify the factory returned the required type
            if not isinstance(parser, Cmd2ArgumentParser):
                builder_name = getattr(parser_builder, "__name__", str(parser_builder))  # type: ignore[unreachable]
                raise TypeError(f"The parser returned by '{builder_name}' must be a Cmd2ArgumentParser or a subclass of it")

        return parser

    def _install_command_function(self, command_func_name: str, command_method: BoundCommandFunc, context: str = "") -> None:
        """Install a new command function into the CLI.