Ticket #12152: 12152-1.diff

django/db/models/base.py

@@ -49 +49 @@
 
         new_class.add_to_class('_meta', Options(meta, **kwargs))
         if not abstract:
-            new_class.add_to_class('DoesNotExist',
-                    subclass_exception('DoesNotExist', ObjectDoesNotExist, module))
-            new_class.add_to_class('MultipleObjectsReturned',
-                    subclass_exception('MultipleObjectsReturned', MultipleObjectsReturned, module))
             if base_meta and not base_meta.abstract:
                 # Non-abstract child classes inherit some attributes from their
                 # non-abstract parent (unless an ABC comes before it in the
@@ -118 +114 @@
         o2o_map = dict([(f.rel.to, f) for f in new_class._meta.local_fields
                 if isinstance(f, OneToOneField)])
 
+        exception_class_bases = []
         for base in parents:
             original_base = base
             if not hasattr(base, '_meta'):
@@ -136 +133 @@
                                      'base class %r' %
                                         (field.name, name, base.__name__))
             if not base._meta.abstract:
+                exception_class_bases.append(base)
                 # Concrete classes...
                 while base._meta.proxy:
                     # Skip over a proxy class to the "real" base it proxies.
@@ -176 +174 @@
                                         (field.name, name, base.__name__))
                 new_class.add_to_class(field.name, copy.deepcopy(field))
 
+        # If a model has non-abstract parent models, the model's inner
+        # exception classes should inherit from theirs.
+        if exception_class_bases:
+            does_not_exist_parents = tuple(getattr(x, 'DoesNotExist')
+                            for x in exception_class_bases)
+            multiple_objects_returned_parents = tuple(getattr(x, 'MultipleObjectsReturned')
+                            for x in exception_class_bases)
+        else:
+            does_not_exist_parents = ObjectDoesNotExist
+            multiple_objects_returned_parents = MultipleObjectsReturned
+        new_class.add_to_class('DoesNotExist',
+                subclass_exception('DoesNotExist',
+                        does_not_exist_parents, module))
+        new_class.add_to_class('MultipleObjectsReturned',
+                subclass_exception('MultipleObjectsReturned',
+                        multiple_objects_returned_parents, module))
+
         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
@@ -669 +684 @@
 if sys.version_info < (2, 5):
     # Prior to Python 2.5, Exception was an old-style class
     def subclass_exception(name, parent, unused):
-        return types.ClassType(name, (parent,), {})
+        return types.ClassType(name,
+                    (parent,) if type(parent) == type else parent, {})
 else:
     def subclass_exception(name, parent, module):
-        return type(name, (parent,), {'__module__': module})
+        return type(name, (parent,) if type(parent) == type else parent,
+                    {'__module__': module})

tests/modeltests/proxy_models/models.py

@@ -205 +205 @@
 >>> MyPersonProxy.objects.all()
 [<MyPersonProxy: Bazza del Frob>, <MyPersonProxy: Foo McBar>, <MyPersonProxy: homer>]
 
+# Proxy models are included in the ancestors for a model's DoesNotExist and MultipleObjectsReturned
+>>> try:
+...     MyPersonProxy.objects.get(name='Zathras')
+... except Person.DoesNotExist:
+...     pass
+>>> try:
+...     MyPersonProxy.objects.get(id__lt=10)
+... except Person.MultipleObjectsReturned:
+...     pass
+>>> try:
+...     StatusPerson.objects.get(name='Zathras')
+... except Person.DoesNotExist:
+...     pass
+>>> sp1 = StatusPerson.objects.create(name='Bazza Jr.')
+>>> sp2 = StatusPerson.objects.create(name='Foo Jr.')
+>>> try:
+...     StatusPerson.objects.get(id__lt=10)
+... except Person.MultipleObjectsReturned:
+...     pass
+
 # And now for some things that shouldn't work...
 #
 # All base classes must be non-abstract

tests/modeltests/model_inheritance/models.py

@@ -38 +38 @@
     class Meta:
         pass
 
+class StudentWorker(Student, Worker):
+    pass
+
 #
 # Abstract base classes with related models
 #
@@ -151 +154 @@
     ...
 AttributeError: type object 'CommonInfo' has no attribute 'objects'
 
+# A StudentWorker which does not exist is both a Student and Worker which does not exist.
+>>> try:
+...     StudentWorker.objects.get(id=1)
+... except Student.DoesNotExist:
+...     pass
+>>> try:
+...     StudentWorker.objects.get(id=1)
+... except Worker.DoesNotExist:
+...     pass
+
+# MultipleObjectsReturned is also inherited.
+>>> sw1 = StudentWorker()
+>>> sw1.name = 'Wilma'
+>>> sw1.age = 35
+>>> sw1.save()
+>>> sw2 = StudentWorker()
+>>> sw2.name = 'Betty'
+>>> sw2.age = 34
+>>> sw2.save()
+>>> try:
+...     StudentWorker.objects.get(id__lt=10)
+... except Student.MultipleObjectsReturned:
+...     pass
+... except Worker.MultipleObjectsReturned:
+...     pass
+
 # Create a Post
 >>> post = Post(title='Lorem Ipsum')
 >>> post.save()
@@ -242 +271 @@
     ...
 DoesNotExist: ItalianRestaurant matching query does not exist.
 
+# An ItalianRestaurant which does not exist is also a Place which does not exist.
+>>> try:
+...     ItalianRestaurant.objects.get(name='The Noodle Void')
+... except Place.DoesNotExist:
+...     pass
+
+# MultipleObjectsReturned is also inherited.
+>>> try:
+...     Restaurant.objects.get(id__lt=10)
+... except Place.MultipleObjectsReturned:
+...     pass
+
 # Related objects work just as they normally do.
 
 >>> s1 = Supplier(name="Joe's Chickens", address='123 Sesame St')