Flake8 Extension to lint for a method newline after a Class definition

Usage

If you are using flake8, you can install this package through pip.

pip install flake8-class-newline

This plugin is then automatically triggered when you run;

flake8

It produces only 1 error type; "CNL100 Class definition does not have a new line."

NOTE; Documentation blocks (or docblocks) should be on the newline, they are therefore ignored by this plugin. See https://www.python.org/dev/peps/pep-0008/#documentation-strings

Example

PEP8 says we should surround every class method with a single blank line. See https://www.python.org/dev/peps/pep-0008/#blank-lines However flake8 is ambiguous about the first method having a blank line above it.

Basically;

class AClassWithoutANewLine(object):
    def a_method(self):
        return 'a_value'

class AClassWithoutANewLineProperty(object):
    @property
    def a_method(self):
        return 'a_value'

or

class AClassWithANewLine(object):

    def a_method(self):
        return 'a_value'

class AClassWithANewLineProperty(object):

    @property
    def a_method(self):
        return 'a_value'

This plugin was made to enforce the latter.

NOTE; properties of a class do not need a surrounding blank line, only methods.

Special Notice

This package was inspired by flake8-quotes created by @zheller. Thanks for the inspiration!