mirror of
https://github.com/PyCQA/flake8.git
synced 2026-03-29 18:46:52 +00:00
54 lines
1.8 KiB
ReStructuredText
54 lines
1.8 KiB
ReStructuredText
.. _formatting-plugins:
|
|
|
|
===========================================
|
|
Developing a Formatting Plugin for Flake8
|
|
===========================================
|
|
|
|
|Flake8| allowed for custom formatting plugins in version
|
|
3.0.0. Let's write a plugin together:
|
|
|
|
.. code-block:: python
|
|
|
|
from flake8.formatting import base
|
|
|
|
|
|
class Example(base.BaseFormatter):
|
|
"""Flake8's example formatter."""
|
|
|
|
pass
|
|
|
|
We notice, as soon as we start, that we inherit from |Flake8|'s
|
|
:class:`~flake8.formatting.base.BaseFormatter` class. If we follow the
|
|
:ref:`instructions to register a plugin <register-a-plugin>` and try to use
|
|
our example formatter, e.g., ``flake8 --format=example`` then
|
|
|Flake8| will fail because we did not implement the ``format`` method.
|
|
Let's do that next.
|
|
|
|
.. code-block:: python
|
|
|
|
class Example(base.BaseFormatter):
|
|
"""Flake8's example formatter."""
|
|
|
|
def format(self, error):
|
|
return 'Example formatter: {0!r}'.format(error)
|
|
|
|
With that we're done. Obviously this isn't a very useful formatter, but it
|
|
should highlight the simplicitly of creating a formatter with Flake8. If we
|
|
wanted to instead create a formatter that aggregated the results and returned
|
|
XML, JSON, or subunit we could also do that. |Flake8| interacts with the
|
|
formatter in two ways:
|
|
|
|
#. It creates the formatter and provides it the options parsed from the
|
|
configuration files and command-line
|
|
|
|
#. It uses the instance of the formatter and calls ``handle`` with the error.
|
|
|
|
By default :meth:`flake8.formatting.base.BaseFormatter.handle` simply calls
|
|
the ``format`` method and then ``write``. Any extra handling you wish to do
|
|
for formatting purposes should override the ``handle`` method.
|
|
|
|
API Documentation
|
|
=================
|
|
|
|
.. autoclass:: flake8.formatting.base.BaseFormatter
|
|
:members:
|