前言

对于这个问题，请使用argparse。RawTextHelpFormatter对我很有帮助。

现在，我想分享如何使用argparse。

我知道这可能和问题无关，

但这些问题已经困扰我一段时间了。

所以我想分享我的经验，希望对别人有所帮助。

开始吧。

第三方模块

Colorama:更改文本颜色:PIP安装Colorama

使ANSI转义字符序列(用于产生彩色终端文本和游标定位)在MS Windows下工作

例子

import colorama
from colorama import Fore, Back
from pathlib import Path
from os import startfile, system

SCRIPT_DIR = Path(__file__).resolve().parent
TEMPLATE_DIR = SCRIPT_DIR.joinpath('.')


def main(args):
    ...


if __name__ == '__main__':
    colorama.init(autoreset=True)

    from argparse import ArgumentParser, RawTextHelpFormatter

    format_text = FormatText([(20, '<'), (60, '<')])
    yellow_dc = format_text.new_dc(fore_color=Fore.YELLOW)
    green_dc = format_text.new_dc(fore_color=Fore.GREEN)
    red_dc = format_text.new_dc(fore_color=Fore.RED, back_color=Back.LIGHTYELLOW_EX)

    script_description = \
        '\n'.join([desc for desc in
                   [f'\n{green_dc(f"python {Path(__file__).name} [REFERENCE TEMPLATE] [OUTPUT FILE NAME]")} to create template.',
                    f'{green_dc(f"python {Path(__file__).name} -l *")} to get all available template',
                    f'{green_dc(f"python {Path(__file__).name} -o open")} open template directory so that you can put your template file there.',
                    # <- add your own description
                    ]])
    arg_parser = ArgumentParser(description=yellow_dc('CREATE TEMPLATE TOOL'),
                                # conflict_handler='resolve',
                                usage=script_description, formatter_class=RawTextHelpFormatter)

    arg_parser.add_argument("ref", help="reference template", nargs='?')
    arg_parser.add_argument("outfile", help="output file name", nargs='?')
    arg_parser.add_argument("action_number", help="action number", nargs='?', type=int)
    arg_parser.add_argument('--list', "-l", dest='list',
                            help=f"example: {green_dc('-l *')} \n"
                                 "description: list current available template. (accept regex)")

    arg_parser.add_argument('--option', "-o", dest='option',
                            help='\n'.join([format_text(msg_data_list) for msg_data_list in [
                                ['example', 'description'],
                                [green_dc('-o open'), 'open template directory so that you can put your template file there.'],
                                [green_dc('-o run'), '...'],
                                [green_dc('-o ...'), '...'],
                                # <- add your own description
                            ]]))

    g_args = arg_parser.parse_args()
    task_run_list = [[False, lambda: startfile('.')] if g_args.option == 'open' else None,
                     [False, lambda: [print(template_file_path.stem) for template_file_path in TEMPLATE_DIR.glob(f'{g_args.list}.py')]] if g_args.list else None,
                     # <- add your own function
                     ]
    for leave_flag, func in [task_list for task_list in task_run_list if task_list]:
        func()
        if leave_flag:
            exit(0)

    # CHECK POSITIONAL ARGUMENTS
    for attr_name, value in vars(g_args).items():
        if attr_name.startswith('-') or value is not None:
            continue
        system('cls')
        print(f'error required values of {red_dc(attr_name)} is None')
        print(f"if you need help, please use help command to help you: {red_dc(f'python {__file__} -h')}")
        exit(-1)
    main(g_args)

FormatText的类在哪里如下

class FormatText:
    __slots__ = ['align_list']

    def __init__(self, align_list: list, autoreset=True):
        """
        USAGE::

            format_text = FormatText([(20, '<'), (60, '<')])
            red_dc = format_text.new_dc(fore_color=Fore.RED)
            print(red_dc(['column 1', 'column 2']))
            print(red_dc('good morning'))
        :param align_list:
        :param autoreset:
        """
        self.align_list = align_list
        colorama.init(autoreset=autoreset)

    def __call__(self, text_list: list):
        if len(text_list) != len(self.align_list):
            if isinstance(text_list, str):
                return text_list
            raise AttributeError
        return ' '.join(f'{txt:{flag}{int_align}}' for txt, (int_align, flag) in zip(text_list, self.align_list))

    def new_dc(self, fore_color: Fore = Fore.GREEN, back_color: Back = ""):  # DECORATOR
        """create a device context"""
        def wrap(msgs):
            return back_color + fore_color + self(msgs) + Fore.RESET
        return wrap

另一种简单的方法是包含文本包。

例如,

import argparse, textwrap
parser = argparse.ArgumentParser(description='some information',
        usage='use "python %(prog)s --help" for more information',
        formatter_class=argparse.RawTextHelpFormatter)

parser.add_argument('--argument', default=somedefault, type=sometype,
        help= textwrap.dedent('''\
        First line
        Second line
        More lines ... '''))

通过这种方式，我们可以避免在每个输出行前面有很长的空白。

usage: use "python your_python_program.py --help" for more information

Prepare input file

optional arguments:
-h, --help            show this help message and exit
--argument ARGUMENT
                      First line
                      Second line
                      More lines ...

我想在描述文本中有手动换行符，并自动换行;但是这里没有一个建议对我有用-所以我最终修改了答案中给出的SmartFormatter类;尽管argparse方法名不是一个公共API，但这是我拥有的(作为一个名为test.py的文件):

import argparse
from argparse import RawDescriptionHelpFormatter

# call with: python test.py -h

class SmartDescriptionFormatter(argparse.RawDescriptionHelpFormatter):
  #def _split_lines(self, text, width): # RawTextHelpFormatter, although function name might change depending on Python
  def _fill_text(self, text, width, indent): # RawDescriptionHelpFormatter, although function name might change depending on Python
    #print("splot",text)
    if text.startswith('R|'):
      paragraphs = text[2:].splitlines()
      rebroken = [argparse._textwrap.wrap(tpar, width) for tpar in paragraphs]
      #print(rebroken)
      rebrokenstr = []
      for tlinearr in rebroken:
        if (len(tlinearr) == 0):
          rebrokenstr.append("")
        else:
          for tlinepiece in tlinearr:
            rebrokenstr.append(tlinepiece)
      #print(rebrokenstr)
      return '\n'.join(rebrokenstr) #(argparse._textwrap.wrap(text[2:], width))
    # this is the RawTextHelpFormatter._split_lines
    #return argparse.HelpFormatter._split_lines(self, text, width)
    return argparse.RawDescriptionHelpFormatter._fill_text(self, text, width, indent)

parser = argparse.ArgumentParser(formatter_class=SmartDescriptionFormatter, description="""R|Blahbla bla blah blahh/blahbla (bla blah-blabla) a blahblah bl a blaha-blah .blah blah

Blah blah bla blahblah, bla blahblah blah blah bl blblah bl blahb; blah bl blah bl bl a blah, bla blahb bl:

  blah blahblah blah bl blah blahblah""")

options = parser.parse_args()

这是它在2.7和3.4中的工作原理:

$ python test.py -h
usage: test.py [-h]

Blahbla bla blah blahh/blahbla (bla blah-blabla) a blahblah bl a blaha-blah
.blah blah

Blah blah bla blahblah, bla blahblah blah blah bl blblah bl blahb; blah bl
blah bl bl a blah, bla blahb bl:

  blah blahblah blah bl blah blahblah

optional arguments:
  -h, --help  show this help message and exit

如果存在默认值，以下python 3格式化器将追加默认值并保留行长。

from argparse import ArgumentParser, ArgumentDefaultsHelpFormatter, \ 
                     RawTextHelpFormatter
import textwrap

class CustomArgumentFormatter(ArgumentDefaultsHelpFormatter, RawTextHelpFormatter):
    """Formats argument help which maintains line length restrictions as well as appends default value if present."""

    def _split_lines(self, text, width):
        text = super()._split_lines(text, width)
        new_text = []

        # loop through all the lines to create the correct wrapping for each line segment.
        for line in text:
            if not line:
                # this would be a new line.
                new_text.append(line)
                continue

            # wrap the line's help segment which preserves new lines but ensures line lengths are
            # honored
            new_text.extend(textwrap.wrap(line, width))

        return new_text

然后用你的新格式化器创建你的参数解析器:

my_arg_parser = ArgumentParser(formatter_class=CustomArgumentFormatter)
# ... add your arguments ...
print(my_arg_parser.format_help())

尝试使用RawTextHelpFormatter来保存所有的格式:

from argparse import RawTextHelpFormatter
parser = ArgumentParser(description='test', formatter_class=RawTextHelpFormatter)

它类似于RawDescriptionHelpFormatter，但不是只应用于描述和epilog, RawTextHelpFormatter也应用于所有帮助文本(包括参数)。

使用RawTextHelpFormatter获取新行并处理缩进的另一种简单方法是

import argparse

parser = argparse.ArgumentParser(
    description='test', formatter_class=argparse.RawTextHelpFormatter)

parser.add_argument('-g', choices=['a', 'b', 'g', 'd', 'e'], default='a',
                    help=('Some option, where\n'
                          ' a = alpha\n'
                          ' b = beta\n'
                          ' g = gamma\n'
                          ' d = delta\n'
                          ' e = epsilon'))

parser.parse_args()

输出为

$ python2 x.py -h
usage: x.py [-h] [-g {a,b,g,d,e}]

test

optional arguments:
  -h, --help      show this help message and exit
  -g {a,b,g,d,e}  Some option, where
                   a = alpha
                   b = beta
                   g = gamma
                   d = delta
                   e = epsilon