Python argparse 模块，_StoreConstAction() 实例源码

def convert_setting_to_command_line_arg(self, action, key, value):
        args = []
        if action is None:
            command_line_key = \
                self.get_command_line_key_for_unknown_config_file_setting(key)
        else:
            command_line_key = action.option_strings[-1]

        if isinstance(action, argparse._StoreTrueAction):
            if value is True:
                args.append(command_line_key)
        elif isinstance(action, argparse._StoreFalseAction):
            if value is False:
                args.append(command_line_key)
        elif isinstance(action, argparse._StoreConstAction):
            if value == action.const:
                args.append(command_line_key)
        elif isinstance(action, argparse._CountAction):
            for _ in range(value):
                args.append(command_line_key)
        elif action is not None and value == action.default:
            pass
        elif isinstance(value, list):
            args.append(command_line_key)
            args.extend([str(e) for e in value])
        else:
            args.append(command_line_key)
            args.append(str(value))
        return args

def convert_setting_to_command_line_arg(self, action, key, value):
        args = []
        if action is None:
            command_line_key = \
                self.get_command_line_key_for_unknown_config_file_setting(key)
        else:
            command_line_key = action.option_strings[-1]

        if isinstance(action, argparse._StoreTrueAction):
            if value is True:
                args.append(command_line_key)
        elif isinstance(action, argparse._StoreFalseAction):
            if value is False:
                args.append(command_line_key)
        elif isinstance(action, argparse._StoreConstAction):
            if value == action.const:
                args.append(command_line_key)
        elif isinstance(action, argparse._CountAction):
            for _ in range(value):
                args.append(command_line_key)
        elif action is not None and value == action.default:
            pass
        elif isinstance(value, list):
            args.append(command_line_key)
            args.extend([str(e) for e in value])
        else:
            args.append(command_line_key)
            args.append(str(value))
        return args

def _get_help_string(self, action):
        help = action.help
        if '(default' not in help and type(action) not in (argparse._StoreConstAction, argparse._StoreTrueAction, argparse._StoreFalseAction):
            if action.default is not argparse.SUPPRESS:
                defaulting_nargs = [argparse.OPTIONAL, argparse.ZERO_OR_MORE]
                if action.option_strings or action.nargs in defaulting_nargs:
                    help += ' (default: %(default)s)'
        return help

def get_input_object(self, action, prefix):
    input_parameters = {}
    input_parameters['class'] = self.get_class(prefix)
    input_parameters['name'] = self.get_id(action, prefix)
    input_parameters['id'] = self.get_id(action, prefix)

    input_type = web.form.Textbox

    if self.get_choices(action):
      input_type = web.form.Dropdown
      input_parameters['args'] = [choice for choice in action.choices]
      if self.get_multiple(action):
        input_parameters['multiple'] = 'multiple'
        input_parameters['size'] = 4
    elif isinstance(action, (argparse._StoreTrueAction, argparse._StoreFalseAction, argparse._StoreConstAction)):
      input_type = web.form.Checkbox
      input_parameters['checked'] = True if action.default else False
      input_parameters['value'] = action.const
    else:
      input_parameters['value'] = action.default if action.default else ""

    if isinstance(action, argparse._SubParsersAction):
      input_parameters['onChange'] = "javascript: update_show(this);"
      input_parameters['value'] = action.choices.keys()[0]

    if len(action.option_strings):
      input_parameters['default'] = action.default
      # if optional argument may be present with either 1 or no parameters, the default shifts
      # to being the no parameter's value. this is mearly to properly display actual values to the user
      if action.nargs == '?':
        input_parameters['value'] = action.const

    # TODO: support these actions: append, append_const, count
    self._actions[self.get_id(action, prefix)] = action
    input_object = input_type(**input_parameters)

    input_object.description = self.get_description(action)
    input_object.nargs = self.get_nargs(action)
    input_object.help = self.get_help(action)
    input_object.disposition = self.get_disposition(action)
    input_object.subparser = self.get_subparser(action)
    input_object.choices = self.get_choices(action)

    return input_object