Move old documentation out of the way

docs/extensions.rst

@@ -1,149 +0,0 @@
-Writing an Extension for Flake8
-===============================
-
-Since Flake8 is now adding support for extensions, we require ``setuptools``
-so we can manage extensions through entry points. If you are making an
-existing tool compatible with Flake8 but do not already require
-``setuptools``, you should probably add it to your list of requirements. Next,
-you'll need to edit your ``setup.py`` file so that upon installation, your
-extension is registered. If you define a class called ``PackageEntryClass``
-then this would look something like the following::
-
-
-    setup(
-        # ...
-        entry_points={
-            'flake8.extension': ['P10 = package.PackageEntryClass'],
-        }
-        # ...
-    )
-
-
-If you intend to publish your extension, choose a unique code prefix
-following the convention for :ref:`error codes <error-codes>`.
-In addition, you can open a request in the `issue tracker
-<https://bitbucket.org/tarek/flake8/issues>`_ to register the prefix in the
-documentation.
-
-.. TODO: describe the API required for the 3 kind of extensions:
-   * physical line checkers
-   * logical line checkers
-   * AST checkers
-
-
-A real example: McCabe
-----------------------
-
-Below is an example from mccabe_ for how to write your ``setup.py`` file for
-your Flake8 extension.
-
-.. code-block:: python
-
-    # https://github.com/flintwork/mccabe/blob/0.2/setup.py#L38:L42
-    # -*- coding: utf-8 -*-
-    from setuptools import setup
-
-    # ...
-
-    setup(
-        name='mccabe',
-
-        # ...
-
-        install_requires=[
-            'setuptools',
-        ],
-        entry_points={
-            'flake8.extension': [
-                'C90 = mccabe:McCabeChecker',
-            ],
-        },
-
-        # ...
-
-    )
-
-In ``mccabe.py`` you can see that extra options are added to the parser when
-flake8 registers the extension:
-
-.. code-block:: python
-
-    # https://github.com/flintwork/mccabe/blob/0.2/mccabe.py#L225:L254
-    class McCabeChecker(object):
-        """McCabe cyclomatic complexity checker."""
-        name = 'mccabe'
-        version = __version__
-        _code = 'C901'
-        _error_tmpl = "C901 %r is too complex (%d)"
-        max_complexity = 0
-
-        def __init__(self, tree, filename):
-            self.tree = tree
-
-        @classmethod
-        def add_options(cls, parser):
-            parser.add_option('--max-complexity', default=-1, action='store',
-                              type='int', help="McCabe complexity threshold")
-            parser.config_options.append('max-complexity')
-
-        @classmethod
-        def parse_options(cls, options):
-            cls.max_complexity = options.max_complexity
-
-        def run(self):
-            if self.max_complexity < 0:
-                return
-            visitor = PathGraphingAstVisitor()
-            visitor.preorder(self.tree, visitor)
-            for graph in visitor.graphs.values():
-                if graph.complexity() >= self.max_complexity:
-                    text = self._error_tmpl % (graph.entity, graph.complexity())
-                    yield graph.lineno, 0, text, type(self)
-
-Since that is the defined entry point in the above ``setup.py``, flake8 finds
-it and uses it to register the extension.
-
-If we wanted the extension or a check to be optional, you can add
-``off_by_default = True`` to our entry point. For example, we could
-update ``mccabe.py`` with this variable as shown below:
-
-.. code-block:: python
-
-    # https://github.com/flintwork/mccabe/blob/0.2/mccabe.py#L225:L254
-    class McCabeChecker(object):
-        """McCabe cyclomatic complexity checker."""
-        name = 'mccabe'
-        version = __version__
-        off_by_default = True
-
-If we wanted to run the optional extension or check, we need to specify the
-error and warnings via the ``--enable-extension`` command line argument. In our
-case, we could run ``flake8 --enable-extension=C90`` which would enable our
-off_by_default example version of the mccabe extension.
-
-
-Existing Extensions
-===================
-
-This is not at all a comprehensive listing of existing extensions but simply a 
-listing of the ones we are aware of:
-
-* `flake8-debugger <https://github.com/JBKahn/flake8-debugger>`_
-
-* `flake8-immediate <https://github.com/schlamar/flake8-immediate>`_
-
-* `flake8-print <https://github.com/JBKahn/flake8-print>`_
-  
-* `flake8-todo <https://github.com/schlamar/flake8-todo>`_
-
-* `pep8-naming <https://github.com/flintwork/pep8-naming>`_
-
-* `radon <https://github.com/rubik/radon>`_
-
-* `flake8-import-order <https://github.com/public/flake8-import-order>`_
-
-* `flake8-respect-noqa <https://pypi.python.org/pypi/flake8-respect-noqa>`_
-
-.. links
-.. _mccabe: https://github.com/flintwork/mccabe
-.. _PyPI: https://pypi.python.org/pypi/