update third-party docs for better reversion support

also mention mptt options

docs/third-party.rst

@@ -1,23 +1,21 @@
 Third-party applications support
 ================================
 
-Django-reversion support
+django-reversion support
 ------------------------
 
-`Django-reversion <https://github.com/etianen/django-reversion>`_ works as
+Support for django-reversion_ works as expected with polymorphic models.
-expected with polymorphic models.  However, they require more setup than
+However, they require more setup than standard models. That's become:
-standard models.  We have to face these problems:
 
 * The children models are not registered in the admin site.
-  You will therefore need to manually register them to django-reversion.
+  You will therefore need to manually register them to django-reversion_.
-* Polymorphic models use
+* Polymorphic models use `multi-table inheritance <https://docs.djangoproject.com/en/dev/topics/db/models/#multi-table-inheritance>`_.
-  `multi-table inheritance <https://docs.djangoproject.com/en/dev/topics/db/models/#multi-table-inheritance>`_.
+  See the `reversion documentation <http://django-reversion.readthedocs.org/en/latest/api.html#multi-table-inheritance>`_
-  The django-reversion wiki explains
+  how to deal with this by adding a ``follow`` field for the primary key.
-  `how to deal with this <https://github.com/etianen/django-reversion/wiki/Low-level-API#multi-table-inheritance>`_.
 
 
 Example
-.......
+~~~~~~~
 
 The admin :ref:`admin-example` becomes:
 
@@ -25,8 +23,8 @@ The admin :ref:`admin-example` becomes:
 
     from django.contrib import admin
     from polymorphic.admin import PolymorphicParentModelAdmin, PolymorphicChildModelAdmin
-    import reversion
+    from reversion.admin import VersionAdmin
-    from reversion import VersionAdmin
+    from reversion import revisions
     from .models import ModelA, ModelB, ModelC
 
 
@@ -51,6 +49,41 @@ The admin :ref:`admin-example` becomes:
             (ModelC, ModelCAdmin),
         )
 
-    reversion.register(ModelB, follow=['modela_ptr'])
+    revisions.register(ModelB, follow=['modela_ptr'])
-    reversion.register(ModelC, follow=['modelb_ptr'])
+    revisions.register(ModelC, follow=['modelb_ptr'])
     admin.site.register(ModelA, ModelAParentAdmin)
+
+.. _django-reversion-compare-support:
+
+django-reversion-compare support
+--------------------------------
+
+The django-reversion-compare_ views work as expected, the admin requires a little tweak.
+In your parent admin, include the following method:
+
+.. code-block:: python
+
+    def compare_view(self, request, object_id, extra_context=None):
+        """Redirect the reversion-compare view to the child admin."""
+        real_admin = self._get_real_admin(object_id)
+        return real_admin.compare_view(request, object_id, extra_context=extra_context)
+
+As the compare view resolves the the parent admin, it uses it's base model to find revisions.
+This doesn't work, since it needs to look for revisions of the child model. Using this tweak,
+the view of the actual child model is used, similar to the way the regular change and delete views are redirected.
+
+
+django-mptt support
+-------------------
+
+Combining polymorphic with django-mptt_ is certainly possible, but not straightforward.
+It involves combining both managers, querysets, models, meta-classes and admin classes
+using multiple inheritance.
+
+The django-polymorphic-tree_ package provides this out of the box.
+
+
+.. _django-reversion: https://github.com/etianen/django-reversion
+.. _django-reversion-compare: https://github.com/jedie/django-reversion-compare
+.. _django-mptt: https://github.com/django-mptt/django-mptt
+.. _django-polymorphic-tree: https://github.com/edoburu/django-polymorphic-tree