config.py 文件源码

def _format_action_invocation(self, action):
        orgstr = argparse.HelpFormatter._format_action_invocation(self, action)
        if orgstr and orgstr[0] != '-': # only optional arguments
            return orgstr
        res = getattr(action, '_formatted_action_invocation', None)
        if res:
            return res
        options = orgstr.split(', ')
        if len(options) == 2 and (len(options[0]) == 2 or len(options[1]) == 2):
            # a shortcut for '-h, --help' or '--abc', '-a'
            action._formatted_action_invocation = orgstr
            return orgstr
        return_list = []
        option_map =  getattr(action, 'map_long_option', {})
        if option_map is None:
            option_map = {}
        short_long = {}
        for option in options:
            if len(option) == 2 or option[2] == ' ':
                continue
            if not option.startswith('--'):
                raise ArgumentError('long optional argument without "--": [%s]'
                                    % (option), self)
            xxoption = option[2:]
            if xxoption.split()[0] not in option_map:
                shortened = xxoption.replace('-', '')
                if shortened not in short_long or \
                   len(short_long[shortened]) < len(xxoption):
                    short_long[shortened] = xxoption
        # now short_long has been filled out to the longest with dashes
        # **and** we keep the right option ordering from add_argument
        for option in options: #
            if len(option) == 2 or option[2] == ' ':
                return_list.append(option)
            if option[2:] == short_long.get(option.replace('-', '')):
                return_list.append(option.replace(' ', '=', 1))
        action._formatted_action_invocation = ', '.join(return_list)
        return action._formatted_action_invocation