pep8 - Python style guide checker

pep8 is a tool to check your Python code against some of the style conventions in PEP 8.

Mailing List

http://groups.google.com/group/pep8

Features

• Plugin architecture: Adding new checks is easy.
• Parseable output: Jump to error location in your editor.
• Small: Just one Python file, requires only stdlib. You can use just the pep8.py file for this purpose.
• Comes with a comprehensive test suite.

Installation

You can install, upgrade, uninstall pep8.py with these commands:

$ sudo pip install pep8
$ sudo pip install --upgrade pep8
$ sudo pip uninstall pep8

Or if you don't have pip:

$ sudo easy_install pep8

There's also a package for Debian/Ubuntu, but it's not always the latest version:

$ sudo apt-get install pep8

Example usage and output

$ pep8 optparse.py
optparse.py:69:11: E401 multiple imports on one line
optparse.py:77:1: E302 expected 2 blank lines, found 1
optparse.py:88:5: E301 expected 1 blank line, found 0
optparse.py:222:34: W602 deprecated form of raising exception
optparse.py:347:31: E211 whitespace before '('
optparse.py:357:17: E201 whitespace after '{'
optparse.py:472:29: E221 multiple spaces before operator
optparse.py:544:21: W601 .has_key() is deprecated, use 'in'

You can also make pep8.py show the source code for each error, and even the relevant text from PEP 8:

$ pep8 --show-source --show-pep8 testsuite/E111.py
testsuite/E111.py:2:3: E111 indentation is not a multiple of four
  print x
  ^
    Use 4 spaces per indentation level.

    For really old code that you don't want to mess up, you can
    continue to use 8-space tabs.

Or you can display how often each error was found:

$ pep8 --statistics -qq --filename=*.py Python-2.5/Lib
232     E201 whitespace after '['
599     E202 whitespace before ')'
631     E203 whitespace before ','
842     E211 whitespace before '('
2531    E221 multiple spaces before operator
4473    E301 expected 1 blank line, found 0
4006    E302 expected 2 blank lines, found 1
165     E303 too many blank lines (4)
325     E401 multiple imports on one line
3615    E501 line too long (82 characters)
612     W601 .has_key() is deprecated, use 'in'
1188    W602 deprecated form of raising exception

Quick help is available on the command line:

$ pep8 -h
Usage: pep8.py [options] input ...

Options:
  --version            show program's version number and exit
  -h, --help           show this help message and exit
  -v, --verbose        print status messages, or debug with -vv
  -q, --quiet          report only file names, or nothing with -qq
  -r, --repeat         (obsolete) show all occurrences of the same error
  --first              show first occurrence of each error
  --exclude=patterns   exclude files or directories which match these comma
                       separated patterns (default: .svn,CVS,.bzr,.hg,.git)
  --filename=patterns  when parsing directories, only check filenames matching
                       these comma separated patterns (default: *.py)
  --select=errors      select errors and warnings (e.g. E,W6)
  --ignore=errors      skip errors and warnings (e.g. E4,W)
  --show-source        show source code for each error
  --show-pep8          show text of PEP 8 for each error
  --statistics         count errors and warnings
  --count              print total number of errors and warnings to standard
                       error and set exit code to 1 if total is not null
  --benchmark          measure processing speed
  --testsuite=dir      run regression tests from dir
  --max-line-length=n  set maximum allowed line length (default 79)
  --doctest            run doctest on myself

Feedback

Your feedback is more than welcome. Write email to johann@rocholl.net or post bugs and feature requests on github:

http://github.com/jcrocholl/pep8/issues

Source download

The source code is currently available on github. Fork away!

http://github.com/jcrocholl/pep8/