Ticket #15279: ticket15279_r15553.diff

django/db/models/fields/__init__.py

@@ -234 +234 @@
     def contribute_to_class(self, cls, name):
         self.set_attributes_from_name(name)
         self.model = cls
+        if not hasattr(self, "_declared_on_class"):
+            self._declared_on_class = cls
+        if not hasattr(self, "_first_concrete_class") and not cls._meta.abstract:
+            self._first_concrete_class = cls
         cls._meta.add_field(self)
-        if self.choices:
-            setattr(cls, 'get_%s_display' % self.name, curry(cls._get_FIELD_display, field=self))
 
     def get_attname(self):
         return self.name

django/db/models/options.py

@@ -10 +10 @@
 from django.utils.translation import activate, deactivate_all, get_language, string_concat
 from django.utils.encoding import force_unicode, smart_str
 from django.utils.datastructures import SortedDict
+from django.utils.functional import curry
 
 try:
     all
@@ -64 +65 @@
         from django.db.backends.util import truncate_name
 
         cls._meta = self
+        self.model = cls
         self.installed = re.sub('\.models$', '', cls.__module__) in settings.INSTALLED_APPS
         # First, construct the default values for these options.
         self.object_name = cls.__name__
@@ -158 +160 @@
         # Insert the given field in the order in which it was created, using
         # the "creation_counter" attribute of the field.
         # Move many-to-many related fields from self.fields into
-        # self.many_to_many.
+        # self.many_to_many. Ignore duplicate fields inherited from a
+        # single abstract base class.
+        try:
+            f = self.get_field(field.name)
+        except FieldDoesNotExist:
+            pass
+        else:
+            if f._declared_on_class == field._declared_on_class and getattr(f, '_first_concrete_class', None) == getattr(field, '_first_concrete_class', None):
+                return
+
         if field.rel and isinstance(field.rel, ManyToManyRel):
             self.local_many_to_many.insert(bisect(self.local_many_to_many, field), field)
             if hasattr(self, '_m2m_cache'):
@@ -173 +184 @@
         if hasattr(self, '_name_map'):
             del self._name_map
 
+        if field.choices:
+            setattr(self.model, 'get_%s_display' % field.name, curry(self.model._get_FIELD_display, field=field))
+
     def add_virtual_field(self, field):
         self.virtual_fields.append(field)
 

tests/modeltests/model_inheritance/models.py

@@ -64 +64 @@
 class Link(Attachment):
     url = models.URLField()
 
+class OrangeAttachment(Attachment):
+    class Meta:
+        abstract = True
+
+class BananaAttachment(Attachment):
+    class Meta:
+        abstract = True
+
 #
 # Multi-table inheritance
 #

tests/modeltests/model_inheritance/tests.py

@@ -4 +4 @@
 from django.test import TestCase
 
 from models import (Chef, CommonInfo, ItalianRestaurant, ParkingLot, Place,
-    Post, Restaurant, Student, StudentWorker, Supplier, Worker, MixinModel)
+    Post, Restaurant, Student, StudentWorker, Supplier, Worker, MixinModel,
+    OrangeAttachment, BananaAttachment)
 
 
 class ModelInheritanceTests(TestCase):
@@ -69 +70 @@
             StudentWorker.objects.get, pk__lt=sw2.pk + 100
         )
 
+    def test_multiple_abstract_inheritance(self):
+        # Define class here to avoid model validation errors while running tests.
+        class SmoothieAttachment(OrangeAttachment, BananaAttachment):
+            class Meta:
+                app_label = 'model_inheritance'
+
+        # There should be no duplicate field names.
+        field_names = [field.name for field in SmoothieAttachment._meta.fields]
+        self.assertEqual(field_names.sort(), list(set(field_names)).sort())
+
     def test_multiple_table(self):
         post = Post.objects.create(title="Lorem Ipsum")
         # The Post model has distinct accessors for the Comment and Link models.