Commit 79d2ee3b authored by Jacob Kaplan-Moss's avatar Jacob Kaplan-Moss
Browse files

Fixed #8309: subclasses now inherit `GenericForeignKey` correctly. There's... 

Fixed #8309: subclasses now inherit `GenericForeignKey` correctly. There's also now an internal API so that other "virtual fields" like GFK can be inherited as well. Thanks, msaelices.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@8855 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent 98e1cc92

django/contrib/contenttypes/generic.py

+1 −2
Original line number Diff line number Diff line
@@ -24,11 +24,10 @@ class GenericForeignKey(object): 
        self.fk_field = fk_field



    def contribute_to_class(self, cls, name):

        # Make sure the fields exist (these raise FieldDoesNotExist,

        # which is a fine error to raise here)

        self.name = name

        self.model = cls

        self.cache_attr = "_%s_cache" % name

        cls._meta.add_virtual_field(self)



        # For some reason I don't totally understand, using weakrefs here doesn't work.

        signals.pre_init.connect(self.instance_pre_init, sender=cls, weak=False)

django/db/models/base.py

+28 −6
Original line number Diff line number Diff line
@@ -87,6 +87,14 @@ class ModelBase(type): 
                # Things without _meta aren't functional models, so they're

                # uninteresting parents.

                continue

                

            # All the fields of any type declared on this model

            new_fields = new_class._meta.local_fields + \

                         new_class._meta.many_to_many + \

                         new_class._meta.virtual_fields

            field_names = set([f.name for f in new_fields])

                

            # Concrete classes...

            if not base._meta.abstract:

                if base in o2o_map:

                    field = o2o_map[base]
@@ -98,13 +106,17 @@ class ModelBase(type): 
                            auto_created=True, parent_link=True)

                    new_class.add_to_class(attr_name, field)

                new_class._meta.parents[base] = field

            

            # .. and abstract ones.

            else:

                # The abstract base class case.

                names = set([f.name for f in new_class._meta.local_fields + new_class._meta.many_to_many])

                for field in base._meta.local_fields + base._meta.local_many_to_many:

                    if field.name in names:

                        raise FieldError('Local field %r in class %r clashes with field of similar name from abstract base class %r'

                                % (field.name, name, base.__name__))

                # Check for clashes between locally declared fields and those on the ABC.

                parent_fields = base._meta.local_fields + base._meta.local_many_to_many

                for field in parent_fields:

                    if field.name in field_names:

                        raise FieldError('Local field %r in class %r clashes '\

                                         'with field of similar name from '\

                                         'abstract base class %r' % \

                                            (field.name, name, base.__name__))

                    new_class.add_to_class(field.name, copy.deepcopy(field))



            # Inherit managers from the abstract base classes.
@@ -115,6 +127,16 @@ class ModelBase(type): 
                if not val or val is manager:

                    new_manager = manager._copy_to_model(new_class)

                    new_class.add_to_class(mgr_name, new_manager)

        

            # Inherit virtual fields (like GenericForeignKey) from the parent class

            for field in base._meta.virtual_fields:

                if base._meta.abstract and field.name in field_names:

                    raise FieldError('Local field %r in class %r clashes '\

                                     'with field of similar name from '\

                                     'abstract base class %r' % \

                                        (field.name, name, base.__name__))

                new_class.add_to_class(field.name, copy.deepcopy(field))

        

        if abstract:

            # Abstract base models can't be instantiated and don't appear in

            # the list of models for an app. We do the final setup for them a

django/db/models/options.py

+4 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ DEFAULT_NAMES = ('verbose_name', 'db_table', 'ordering', 
class Options(object):

    def __init__(self, meta, app_label=None):

        self.local_fields, self.local_many_to_many = [], []

        self.virtual_fields = []

        self.module_name, self.verbose_name = None, None

        self.verbose_name_plural = None

        self.db_table = ''
@@ -155,6 +156,9 @@ class Options(object): 
        if hasattr(self, '_name_map'):

            del self._name_map



    def add_virtual_field(self, field):

        self.virtual_fields.append(field)



    def setup_pk(self, field):

        if not self.pk and field.primary_key:

            self.pk = field

tests/modeltests/generic_relations/models.py

+9 −0
Original line number Diff line number Diff line
@@ -27,6 +27,9 @@ class TaggedItem(models.Model): 
    def __unicode__(self):

        return self.tag



class ValuableTaggedItem(TaggedItem):

    value = models.PositiveIntegerField()



class Comparison(models.Model):

    """

    A model that tests having multiple GenericForeignKeys
@@ -204,6 +207,12 @@ __test__ = {'API_TESTS':""" 
>>> Comparison.objects.all()

[<Comparison: tiger is stronger than None>]



# GenericForeignKey should work with subclasses (see #8309)

>>> quartz = Mineral.objects.create(name="Quartz", hardness=7)

>>> valuedtag = ValuableTaggedItem(content_object=quartz, tag="shiny", value=10)

>>> valuedtag.save()

>>> valuedtag.content_object

<Mineral: Quartz>



# GenericInlineFormSet tests ##################################################