pylama 8.3.2

Code audit tool for python

Code audit tool for Python. Pylama wraps these tools:

• pycodestyle (formerly pep8) © 2012-2013, Florent Xicluna;

• pydocstyle (formerly pep257 by Vladimir Keleshev) © 2014, Amir Rachum;

• PyFlakes © 2005-2013, Kevin Watters;

• Mccabe © Ned Batchelder;

• Pylint © 2013, Logilab;

• Radon © Michele Lacchia

• eradicate © Steven Myint;

• Mypy © Jukka Lehtosalo and contributors;

• Vulture © Jendrik Seipp and contributors;

Docs are available at https://klen.github.io/pylama/. Pull requests with documentation enhancements and/or fixes are awesome and most welcome.

Contents

• Requirements:

• Installation:

• Quickstart

• Set Pylama (checkers) options

  • Command line options

  • File modelines

  • Skip lines (noqa)

  • Configuration file

  • Set code-checkers’ options

  • Set options for file (group of files)

• Pytest integration

• Writing a linter

  • Example:

  • Run pylama from python code

  • Bug tracker

  • Contributing

    • Contributors

  • License

Requirements:

• Python (3.7, 3.8, 3.9, 3.10)

• If your tests are failing on Win platform you are missing: curses - http://www.lfd.uci.edu/~gohlke/pythonlibs/ (The curses library supplies a terminal-independent screen-painting and keyboard-handling facility for text-based terminals)

For python versions < 3.7 install pylama 7.7.1

Installation:

Pylama can be installed using pip:

$ pip install pylama

You may optionally install the requirements with the library:

$ pip install pylama[mypy]
$ pip install pylama[pylint]
$ pip install pylama[eradicate]
$ pip install pylama[radon]
$ pip install pylama[vulture]

Or install them all:

$ pip install pylama[all]

Quickstart

Pylama is easy to use and really fun for checking code quality. Just run pylama and get common output from all pylama plugins (pycodestyle, PyFlakes, etc.)

Recursively check the current directory.

$ pylama

Recursively check a path.

$ pylama <path_to_directory_or_file>

Ignore errors

$ pylama -i W,E501

Note

You can choose a group of errors like D, E1, etc, or special errors like C0312

Choose code checkers

$ pylama -l "pycodestyle,mccabe"

Set Pylama (checkers) options

Command line options

$ pylama --help

usage: pylama [-h] [--version] [--verbose] [--options FILE] [--linters LINTERS] [--from-stdin] [--concurrent] [--format {pydocstyle,pycodestyle,pylint,parsable,json}] [--abspath]
              [--max-line-length MAX_LINE_LENGTH] [--select SELECT] [--ignore IGNORE] [--skip SKIP] [--sort SORT] [--report REPORT] [--hook] [--max-complexity MAX_COMPLEXITY]
              [--pydocstyle-convention {pep257,numpy,google}] [--pylint-confidence {HIGH,INFERENCE,INFERENCE_FAILURE,UNDEFINED}]
              [paths ...]

Code audit tool for python.

positional arguments:
  paths                 Paths to files or directories for code check.

optional arguments:
  -h, --help            show this help message and exit
  --version             show program's version number and exit
  --verbose, -v         Verbose mode.
  --options FILE, -o FILE
                        Specify configuration file. Looks for pylama.ini, setup.cfg, tox.ini, or pytest.ini in the current directory (default: None)
  --linters LINTERS, -l LINTERS
                        Select linters. (comma-separated). Choices are eradicate,mccabe,mypy,pycodestyle,pydocstyle,pyflakes,pylint,isort.
  --from-stdin          Interpret the stdin as a python script, whose filename needs to be passed as the path argument.
  --concurrent, --async
                        Enable async mode. Useful for checking a lot of files.
  --format {pydocstyle,pycodestyle,pylint,parsable,json}, -f {pydocstyle,pycodestyle,pylint,parsable,json}
                        Choose output format.
  --abspath, -a         Use absolute paths in output.
  --max-line-length MAX_LINE_LENGTH, -m MAX_LINE_LENGTH
                        Maximum allowed line length
  --select SELECT, -s SELECT
                        Select errors and warnings. (comma-separated list)
  --ignore IGNORE, -i IGNORE
                        Ignore errors and warnings. (comma-separated)
  --skip SKIP           Skip files by masks (comma-separated, Ex. */messages.py)
  --sort SORT           Sort result by error types. Ex. E,W,D
  --report REPORT, -r REPORT
                        Send report to file [REPORT]
  --hook                Install Git (Mercurial) hook.
  --max-complexity MAX_COMPLEXITY
                        Max complexity threshold

Note

additional options may be available depending on installed linters

File modelines

You can set options for Pylama inside a source file. Use a pylama modeline for this, anywhere in the file.

Format:

# pylama:{name1}={value1}:{name2}={value2}:...

For example, ignore warnings except W301:

# pylama:ignore=W:select=W301

Disable code checking for current file:

# pylama:skip=1

Those options have a higher priority.

Skip lines (noqa)

Just add # noqa at the end of a line to ignore:

def urgent_fuction():
    unused_var = 'No errors here' # noqa

Configuration file

Pylama looks for a configuration file in the current directory.

You can use a “global” configuration, stored in .pylama.ini in your home directory. This will be used as a fallback configuration.

The program searches for the first matching ini-style configuration file in the directories of command line argument. Pylama looks for the configuration in this order:

./pylama.ini
./setup.cfg
./tox.ini
./pytest.ini
~/.pylama.init

The --option / -o argument can be used to specify a configuration file.

Pylama searches for sections whose names start with pylama.

The pylama section configures global options like linters and skip.

[pylama]
format = pylint
skip = */.tox/*,*/.env/*
linters = pylint,mccabe
ignore = F0401,C0111,E731

Set code-checkers’ options

You can set options for a special code checkers with pylama configurations.

[pylama:pyflakes]
builtins = _

[pylama:pycodestyle]
max_line_length = 100

[pylama:pylint]
max_line_length = 100
disable = R

See code-checkers’ documentation for more info. Note that dashes are replaced by underscores (e.g. Pylint’s max-line-length becomes max_line_length).

Set options for file (group of files)

You can set options for special file (group of files) with sections:

The options have a higher priority than in the pylama section.

[pylama:*/pylama/main.py]
ignore = C901,R0914,W0212
select = R

[pylama:*/tests.py]
ignore = C0110

[pylama:*/setup.py]
skip = 1

Pytest integration

Pylama has Pytest support. The package automatically registers itself as a pytest plugin during installation. Pylama also supports the pytest_cache plugin.

Check files with pylama

pytest --pylama ...

The recommended way to set pylama options when using pytest — configuration files (see below).

Writing a linter

You can write a custom extension for Pylama. The custom linter should be a python module. Its name should be like ‘pylama_<name>’.

In ‘setup.py’, ‘pylama.linter’ entry point should be defined.

setup(
    # ...
    entry_points={
        'pylama.linter': ['lintername = pylama_lintername.main:Linter'],
    }
    # ...
)

‘Linter’ should be an instance of ‘pylama.lint.Linter’ class. It must implement two methods:

1. allow takes a path argument and returns true if the linter can check this file for errors.

2. run takes a path argument and meta keyword arguments and returns a list of errors.

Example:

Just a virtual ‘WOW’ checker.

setup.py:

setup(
    name='pylama_wow',
    install_requires=[ 'setuptools' ],
    entry_points={
        'pylama.linter': ['wow = pylama_wow.main:Linter'],
    }
    # ...
)

pylama_wow.py:

from pylama.lint import Linter as BaseLinter

class Linter(BaseLinter):

    def allow(self, path):
        return 'wow' in path

    def run(self, path, **meta):
        with open(path) as f:
            if 'wow' in f.read():
                return [{
                    lnum: 0,
                    col: 0,
                    text: '"wow" has been found.',
                    type: 'WOW'
                }]

Run pylama from python code

from pylama.main import check_paths, parse_options

# Use and/or modify 0 or more of the options defined as keys in the variable my_redefined_options below.
# To use defaults for any option, remove that key completely.
my_redefined_options = {
    'linters': ['pep257', 'pydocstyle', 'pycodestyle', 'pyflakes' ...],
    'ignore': ['D203', 'D213', 'D406', 'D407', 'D413' ...],
    'select': ['R1705' ...],
    'sort': 'F,E,W,C,D,...',
    'skip': '*__init__.py,*/test/*.py,...',
    'async': True,
    'force': True
    ...
}
# relative path of the directory in which pylama should check
my_path = '...'

options = parse_options([my_path], **my_redefined_options)
errors = check_paths(my_path, options, rootdir='.')

Bug tracker

If you have any suggestions, bug reports or annoyances please report them to the issue tracker at https://github.com/klen/pylama/issues

Contributing

Development of pylama happens at GitHub: https://github.com/klen/pylama

Contributors

See AUTHORS.

License

This is free software. You are permitted to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of it, under the terms of the MIT License. See LICENSE file for the complete license.

This software is provided WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See LICENSE file for the complete disclaimer.