pep8 1.4

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:

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

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

Example usage and output

$ pep8 --first 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/E40.py
testsuite/E40.py:2:10: E401 multiple imports on one line
import os, sys
         ^
    Imports should usually be on separate lines.

    Okay: import os\nimport sys
    E401: import sys, os

Or you can display how often each error was found:

$ pep8 --statistics -qq 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

Links

• Read the documentation

• Fork me on GitHub

1.4 (2012-12-22)

• Report E226 instead of E225 for optional white space around common operators (*, **, /, + and -). This new error code is ignored in the default configuration because PEP 8 recommends to “use your own judgement”. (Issue #96)

• Lines with a # nopep8 at the end will not issue errors on line length E501 or continuation line indentation E12*. (Issue #27)

• Fix AssertionError when the source file contains an invalid line ending "\r\r\n". (Issue #119)

• Read the [pep8] section of tox.ini or setup.cfg if present. (Issue #93 and #141)

• Add the Sphinx-based documentation, and publish it on http://pep8.readthedocs.org/. (Issue #105)

1.3.4 (2012-12-18)

• Fix false positive E124 and E128 with comments. (Issue #100)

• Fix error on stdin when running with bpython. (Issue #101)

• Fix false positive E401. (Issue #104)

• Report E231 for nested dictionary in list. (Issue #142)

• Catch E271 at the beginning of the line. (Issue #133)

• Fix false positive E126 for multi-line comments. (Issue #138)

• Fix false positive E221 when operator is preceded by a comma. (Issue #135)

• Fix --diff failing on one-line hunk. (Issue #137)

• Fix the --exclude switch for directory paths. (Issue #111)

• Use - filename to read from standard input. (Issue #128)

1.3.3 (2012-06-27)

• Fix regression with continuation line checker. (Issue #98)

1.3.2 (2012-06-26)

• Revert to the previous behaviour for --show-pep8: do not imply --first. (Issue #89)

• Add E902 for IO errors. (Issue #87)

• Fix false positive for E121, and missed E124. (Issue #92)

• Set a sensible default path for config file on Windows. (Issue #95)

• Allow verbose in the configuration file. (Issue #91)

• Show the enforced max-line-length in the error message. (Issue #86)

1.3.1 (2012-06-18)

• Explain which configuration options are expected. Accept and recommend the options names with hyphen instead of underscore. (Issue #82)

• Do not read the user configuration when used as a module (except if config_file=True is passed to the StyleGuide constructor).

• Fix wrong or missing cases for the E12 series.

• Fix cases where E122 was missed. (Issue #81)

1.3 (2012-06-15)

• Remove global configuration and refactor the library around a StyleGuide class; add the ability to configure various reporters. (Issue #35 and #66)

• Read user configuration from ~/.config/pep8 and local configuration from ./.pep8. (Issue #22)

• Fix E502 for backslash embedded in multi-line string. (Issue #68)

• Fix E225 for Python 3 iterable unpacking (PEP 3132). (Issue #72)

• Enable the new checkers from the E12 series in the default configuration.

• Suggest less error-prone alternatives for E712 errors.

• Rewrite checkers to run faster (E22, E251, E27).

• Fixed a crash when parsed code is invalid (too many closing brackets).

• Fix E127 and E128 for continuation line indentation. (Issue #74)

• New option --format to customize the error format. (Issue #23)

• New option --diff to check only modified code. The unified diff is read from STDIN. Example: hg diff | pep8 --diff (Issue #39)

• Correctly report the count of failures and set the exit code to 1 when the --doctest or the --testsuite fails.

• Correctly detect the encoding in Python 3. (Issue #69)

• Drop support for Python 2.3, 2.4 and 3.0. (Issue #78)

1.2 (2012-06-01)

• Add E121 through E128 for continuation line indentation. These checks are disabled by default. If you want to force all checks, use switch --select=E,W. Patch by Sam Vilain. (Issue #64)

• Add E721 for direct type comparisons. (Issue #47)

• Add E711 and E712 for comparisons to singletons. (Issue #46)

• Fix spurious E225 and E701 for function annotations. (Issue #29)

• Add E502 for explicit line join between brackets.

• Fix E901 when printing source with --show-source.

• Report all errors for each checker, instead of reporting only the first occurence for each line.

• Option --show-pep8 implies --first.

1.1 (2012-05-24)

• Add E901 for syntax errors. (Issues #63 and #30)

• Add E271, E272, E273 and E274 for extraneous whitespace around keywords. (Issue #57)

• Add tox.ini configuration file for tests. (Issue #61)

• Add .travis.yml configuration file for continuous integration. (Issue #62)

1.0.1 (2012-04-06)

• Fix inconsistent version numbers.

1.0 (2012-04-04)

• Fix W602 raise to handle multi-char names. (Issue #53)

0.7.0 (2012-03-26)

• Now --first prints only the first occurence of each error. The --repeat flag becomes obsolete because it is the default behaviour. (Issue #6)

• Allow to specify --max-line-length. (Issue #36)

• Make the shebang more flexible. (Issue #26)

• Add testsuite to the bundle. (Issue #25)

• Fixes for Jython. (Issue #49)

• Add PyPI classifiers. (Issue #43)

• Fix the --exclude option. (Issue #48)

• Fix W602, accept raise with 3 arguments. (Issue #34)

• Correctly select all tests if DEFAULT_IGNORE == ''.

0.6.1 (2010-10-03)

• Fix inconsistent version numbers. (Issue #21)

0.6.0 (2010-09-19)

• Test suite reorganized and enhanced in order to check more failures with fewer test files. Read the run_tests docstring for details about the syntax.

• Fix E225: accept print >>sys.stderr, "..." syntax.

• Fix E501 for lines containing multibyte encoded characters. (Issue #7)

• Fix E221, E222, E223, E224 not detected in some cases. (Issue #16)

• Fix E211 to reject v = dic['a'] ['b']. (Issue #17)

• Exit code is always 1 if any error or warning is found. (Issue #10)

• --ignore checks are now really ignored, especially in conjunction with --count. (Issue #8)

• Blank lines with spaces yield W293 instead of W291: some developers want to ignore this warning and indent the blank lines to paste their code easily in the Python interpreter.

• Fix E301: do not require a blank line before an indented block. (Issue #14)

• Fix E203 to accept NumPy slice notation a[0, :]. (Issue #13)

• Performance improvements.

• Fix decoding and checking non-UTF8 files in Python 3.

• Fix E225: reject True+False when running on Python 3.

• Fix an exception when the line starts with an operator.

• Allow a new line before closing ), } or ]. (Issue #5)

0.5.0 (2010-02-17)

• Changed the --count switch to print to sys.stderr and set exit code to 1 if any error or warning is found.

• E241 and E242 are removed from the standard checks. If you want to include these checks, use switch --select=E,W. (Issue #4)

• Blank line is not mandatory before the first class method or nested function definition, even if there’s a docstring. (Issue #1)

• Add the switch --version.

• Fix decoding errors with Python 3. (Issue #13 [1])

• Add --select option which is mirror of --ignore.

• Add checks E261 and E262 for spaces before inline comments.

• New check W604 warns about deprecated usage of backticks.

• New check W603 warns about the deprecated operator <>.

• Performance improvement, due to rewriting of E225.

• E225 now accepts:

  • no whitespace after unary operator or similar. (Issue #9 [1])

  • lambda function with argument unpacking or keyword defaults.

• Reserve “2 blank lines” for module-level logical blocks. (E303)

• Allow multi-line comments. (E302, issue #10 [1])

0.4.2 (2009-10-22)

• Decorators on classes and class methods are OK now.

0.4 (2009-10-20)

• Support for all versions of Python from 2.3 to 3.1.

• New and greatly expanded self tests.

• Added --count option to print the total number of errors and warnings.

• Further improvements to the handling of comments and blank lines. (Issue #1 [1] and others changes.)

• Check all py files in directory when passed a directory (Issue #2 [1]). This also prevents an exception when traversing directories with non *.py files.

• E231 should allow commas to be followed by ). (Issue #3 [1])

• Spaces are no longer required around the equals sign for keyword arguments or default parameter values.

0.3.1 (2009-09-14)

• Fixes for comments: do not count them when checking for blank lines between items.

• Added setup.py for pypi upload and easy_installability.

0.2 (2007-10-16)

• Loads of fixes and improvements.

0.1 (2006-10-01)

• First release.