=============================
Polyfill for Flake8 Plugins

flake8-polyfill is a package that provides some compatibility helpers for
Flake8 plugins that intend to support Flake8 2.x and 3.x simultaneously.

Installation

.. code-block:: bash

pip install flake8-polyfill

Usage

Option Handling

One problem area with compatibility with Flake8 2.x and 3.x is the registering
options and receiving the parsed values.

Flake8 3.0 added extra parameters to the add_option method which don't
have the same effect on Flake8 2.x. To accomodate the change, this polyfill
module allows you to do:

.. code-block:: python

from flake8_polyfill import options

class MyFlake8Plugin(object):
    @classmethod
    def add_options(cls, parser):
        options.register(parser, '--my-long-option-name',
                         parse_from_config=True,
                         comma_separated_list=True,
                         default='...',
                         help='...')
        options.register(parser, '-m', '--my-other-long-option-name',
                         parse_from_config=True,
                         normalize_paths=True,
                         default='...',
                         help='...')

    @classmethod
    def parse_options(cls, values):
        cls.my_long_option_name = values.my_long_option_name
        cls.my_other_long_option_name = values.my_other_long_option_name

And have the code work the same way on both versions.

Retrieving Standard In

Until Flake8 2.6, getting the code on standard in from a plugin has been
simple:

.. code-block:: python

import pep8

stdin = pep8.get_stdin_value()

In 2.6 you now have to know whether to use pep8 or pycodestyle since
Flake8 2.6 made a hard change to pycodestyle.

The reason you need to know which module to use is because standard in can be
exhausted and Flake8 does some work to cache the value so that call always
returns the desired data.

In 3.0, Flake8 no longer monkey-patches those modules.

To accommodate this, this package provides:

.. code-block:: python

from flake8_polyfill import stdin

stdin.monkey_patch('all')
stdin.monkey_patch('pep8')
stdin.monkey_patch('pycodestyle')

This allows you to have the polyfill module monkey-patch what you want so it
is always monkey-patched. It will also do so in an intelligent way.

Version Comparison

Flake8 2.x did not include an object that would allow for easy version
comparison. Flake8 3.0, however, added a __version_info__ attribute. For
consistency, Flake8 Polyfill will turn 2.x's version string into a tuple
suitable for comparison.

.. code-block:: python

from flake8_polyfill import version

if (2, 4) <= version.version_info < (2, 6):
    # ...
elif (2, 6) <= version.version_info < (3, 0):
    # ...
elif (3, 0) <= version.version_info < (4, 0):
    # ...

License

MIT

Creator

Ian Cordasco

Package profile

flake8-polyfill

Releases

Release table

PyPI Downloads

Dependencies

Details

Project URLs

Dependencies

Package description