====== Flake8 ======

===== Basic usage =====
Documentation:
  * http://flake8.pycqa.org/en/latest/

Install:
<code>
pip install flake8
</code>

To use it for a folder:
<code>
# for the current path
flake8
# or
python -m flake8
# or
flake8 /the/path
</code>

To use it for a file:
<code>
flake8 path/to/file.py
</code>

The output format is: \\
''file path : line number : column number : error code : short description''

Flake8 will exit with code 1 if there are errors. You can change this using the parameter: ''<nowiki>--exit-zero</nowiki>''

Error code prefix:
  * E*/W*: pep8 errors and warnings ─ https://pep8.readthedocs.io/en/latest/intro.html#error-codes
  * F*: PyFlakes codes ─ https://flake8.pycqa.org/en/latest/user/error-codes.html
  * C9*: McCabe complexity plugin mccabe
  * N8*: Naming Conventions plugin pep8-naming ─ https://github.com/PyCQA/pep8-naming

==== Configuration ====

You can configure the flake8 analysis using its command parameters (http://flake8.pycqa.org/en/latest/user/options.html) or placing them in a file named ''setup.cfg'' in the project root.
<code>
[flake8]
exclude = .git,*migrations*
max-line-length = 119
</code>

==== Ignoring errors ====

Just add # noqa in the end of the line.
<code>
def ready(self):
    import cmdbox.profiles.signals.handlers  # noqa
</code>
Or you can pass the specific error code you want to ignore:
<code>
import cmdbox.profiles.signals.handlers  # noqa: F401
</code>

==== Using it with... ====
  * Pycharm
    * https://foxmask.net/post/2016/02/17/pycharm-running-flake8/
    * https://gist.github.com/tossmilestone/23139d870841a3d5cba2aea28da1a895
  * Atom
    * https://atom.io/packages/linter-flake8
  * Vim
    * https://github.com/nvie/vim-flake8
  * SublimeText
    * https://github.com/dreadatour/Flake8Lint
    * https://github.com/SublimeLinter/SublimeLinter-flake8
  * Visual Studio Code
    * https://code.visualstudio.com/docs/python/linting

==== Interesting usages ====
Parameters:
  * ''<nowiki>--count</nowiki>'' to print the number of errors.
  * ''<nowiki>--select=E4,E51,W234</nowiki>'' to select which errors analyse.
  * ''<nowiki>--ignore=E4,E51,W234</nowiki>'' to select which errors ignore.
  * ''<nowiki>--show-source</nowiki>'' to show the code where the error was found.
  * ''<nowiki>--output-file=OUTPUT_FILE</nowiki>'' to redirect the output to a text file.
  * ''<nowiki>--config=CONFIG</nowiki>'' to select the config file.
  * ''<nowiki>--statistics</nowiki>'' to show statistics about errors and warnings.

=== Using hooks for version control ===

http://flake8.pycqa.org/en/latest/user/using-hooks.html

You can stop a commit if flake8 find errors.


==== Plugins ====

To see which plugins are enabled:
<code>
flake8 --version
</code>

To temporally enable disabled plugins: ''<nowiki>--enabled-extensions=ENABLED_EXTENSIONS</nowiki>''.