pep8 是一个遵守 PEP8 编码规范的 Python 代码检测工具。
安装
pip install pep8
PEP8 错误码
| 错误码 | 含义 |
|---|---|
| E1 | Indentation |
| E101 | indentation contains mixed spaces and tabs |
| E111 | indentation is not a multiple of four |
| E112 | expected an indented block |
| E113 | unexpected indentation |
| E114 | indentation is not a multiple of four (comment) |
| E115 | expected an indented block (comment) |
| E116 | unexpected indentation (comment) |
| E121 (*^) | continuation line under-indented for hanging indent |
| E122 (^) | continuation line missing indentation or outdented |
| E123 (*) | closing bracket does not match indentation of opening bracket’s line |
| E124 (^) | closing bracket does not match visual indentation |
| E125 (^) | continuation line with same indent as next logical line |
| E126 (*^) | continuation line over-indented for hanging indent |
| E127 (^) | continuation line over-indented for visual indent |
| E128 (^) | continuation line under-indented for visual indent |
| E129 (^) | visually indented line with same indent as next logical line |
| E131 (^) | continuation line unaligned for hanging indent |
| E133 (*) | closing bracket is missing indentation |
| E2 | Whitespace |
| E201 | whitespace after ‘(‘ |
| E202 | whitespace before ‘)’ |
| E203 | whitespace before ‘:’ |
| E211 | whitespace before ‘(‘ |
| E221 | multiple spaces before operator |
| E222 | multiple spaces after operator |
| E223 | tab before operator |
| E224 | tab after operator |
| E225 | missing whitespace around operator |
| E226 (*) | missing whitespace around arithmetic operator |
| E227 | missing whitespace around bitwise or shift operator |
| E228 | missing whitespace around modulo operator |
| E231 | missing whitespace after ‘,’, ‘;’, or ‘:’ |
| E241 (*) | multiple spaces after ‘,’ |
| E242 (*) | tab after ‘,’ |
| E251 | unexpected spaces around keyword / parameter equals |
| E261 | at least two spaces before inline comment |
| E262 | inline comment should start with ‘# ‘ |
| E265 | block comment should start with ‘# ‘ |
| E266 | too many leading ‘#’ for block comment |
| E271 | multiple spaces after keyword |
| E272 | multiple spaces before keyword |
| E273 | tab after keyword |
| E274 | tab before keyword |
| E3 | Blank line |
| E301 | expected 1 blank line, found 0 |
| E302 | expected 2 blank lines, found 0 |
| E303 | too many blank lines (3) |
| E304 | blank lines found after function decorator |
| E4 | Import |
| E401 | multiple imports on one line |
| E402 | module level import not at top of file |
| E5 | Line length |
| E501 (^) | line too long (82 > 79 characters) |
| E502 | the backslash is redundant between brackets |
| E7 | Statement |
| E701 | multiple statements on one line (colon) |
| E702 | multiple statements on one line (semicolon) |
| E703 | statement ends with a semicolon |
| E704 (*) | multiple statements on one line (def) |
| E711 (^) | comparison to None should be ‘if cond is None:’ |
| E712 (^) | comparison to True should be ‘if cond is True:’ or ‘if cond:’ |
| E713 | test for membership should be ‘not in’ |
| E714 | test for object identity should be ‘is not’ |
| E721 (^) | do not compare types, use ‘isinstance()’ |
| E731 | do not assign a lambda expression, use a def |
| E9 | Runtime |
| E901 | SyntaxError or IndentationError |
| E902 | IOError |
| W1 | Indentation warning |
| W191 | indentation contains tabs |
| W2 | Whitespace warning |
| W291 | trailing whitespace |
| W292 | no newline at end of file |
| W293 | blank line contains whitespace |
| W3 | Blank line warning |
| W391 | blank line at end of file |
| W5 | Line break warning |
| W503 | line break occurred before a binary operator |
| W6 | Deprecation warning |
| W601 | .has_key() is deprecated, use ‘in’ |
| W602 | deprecated form of raising exception |
| W603 | ‘<>’ is deprecated, use ‘!=’ |
| W604 | backticks are deprecated, use ‘repr()’ |
(*)默认配置中，E121、E123、E126、E133、E226、E241、E242、E704 是被忽略的，因为这些规则没有被一致认可，PEP 8 也非强制要求。而且，其中的 E133 和 E123 是互斥的。使用--hang-关闭报告 E133。(^)这些检测可以通过在代码中使用# noqa注释而关闭。比如：- 注释中的长字符串，可能是不便于折断的，比如 URL。
- 还有通过三个反引号定义的字符串中，可能有长的字符串，折断的话就违背了使用这种方法定义字符串的初衷了。
使用方法
列出你的代码违反了哪几条：
pep8 code.py --first --select E,W --format '%(code)s: %(text)s'
集成到 Vim
- 下载插件 https://www.vim.org/scripts/script.php?script_id=2914
- 放到
~/.vim/ftplugin/python/目录。
利用 vim 的 filetype 插件，在/usr/share/vim/vim74/ftplugin。 - 打开 vim，输入
:filetype，看看插件是否开启。如果不是，在配置文件（~/.vimrc）中加一行：filetype plugin on。 - 用 vim 打开一个 py 文件，按 F5 看看是否有 Quickfix List 出现，或者左下角是否有提示 “PEP8 correct”，有两者其一说明安装成功。
我的实践
pep8 . --ignore E501
参考
- Python 软件基金会，PEP 0008 -- Style Guide for Python Code
- readthedocs.org，pep8
