Ticket #8070: 8070.patch

django/db/models/base.py

@@ -200 +200 @@
         # keywords, or default.
 
         for field in fields_iter:
+            rel_obj = None
             if kwargs:
                 if isinstance(field.rel, ManyToOneRel):
                     try:
@@ -216 +217 @@
                         # pass in "None" for related objects if it's allowed.
                         if rel_obj is None and field.null:
                             val = None
-                        else:
-                            try:
-                                val = getattr(rel_obj, field.rel.get_related_field().attname)
-                            except AttributeError:
-                                raise TypeError("Invalid value: %r should be a %s instance, not a %s" %
-                                    (field.name, field.rel.to, type(rel_obj)))
                 else:
                     val = kwargs.pop(field.attname, field.get_default())
             else:
                 val = field.get_default()
-            setattr(self, field.attname, val)
+            # If we got passed a related instance, set it using the field.name
+            # instead of field.attname (e.g. "user" instead of "user_id") so
+            # that the object gets properly cached (and type checked) by the
+            # RelatedObjectDescriptor.
+            if rel_obj:
+                setattr(self, field.name, rel_obj)
+            else:
+                setattr(self, field.attname, val)
 
         if kwargs:
             for prop in kwargs.keys():

tests/modeltests/many_to_one/models.py

@@ -46 +46 @@
 
 # Article objects have access to their related Reporter objects.
 >>> r = a.reporter
+# These are strings instead of unicode strings because that's what was used in
+# for the creation of this reporter (and we haven't refreshed the data from the
+# database, which always returns unicode strings).
 >>> r.first_name, r.last_name
-(u'John', u'Smith')
+('John', 'Smith')
 
 # Create an Article via the Reporter object.
 >>> new_article = r.article_set.create(headline="John's second story", pub_date=datetime(2005, 7, 29))

tests/regressiontests/many_to_one_regress/models.py

@@ -55 +55 @@
 <Child: Child object>
 
 #
-# Tests of ForeignKey assignment and the related-object cache (see #6886)
+# Tests of ForeignKey assignment and the related-object cache (see #6886).
 #
 >>> p = Parent.objects.create(name="Parent")
 >>> c = Child.objects.create(name="Child", parent=p)
 
-# Look up the object again so that we get a "fresh" object
+# Look up the object again so that we get a "fresh" object.
 >>> c = Child.objects.get(name="Child")
 >>> p = c.parent
 
-# Accessing the related object again returns the exactly same object
+# Accessing the related object again returns the exactly same object.
 >>> c.parent is p
 True
 
-# But if we kill the cache, we get a new object
+# But if we kill the cache, we get a new object.
 >>> del c._parent_cache
 >>> c.parent is p
 False
 
-# Assigning a new object results in that object getting cached immediately
+# Assigning a new object results in that object getting cached immediately.
 >>> p2 = Parent.objects.create(name="Parent 2")
 >>> c.parent = p2
 >>> c.parent is p2
@@ -91 +91 @@
     ...
 ValueError: Cannot assign "<First: First object>": "Child.parent" must be a "Parent" instance.
 
-# Test of multiple ForeignKeys to the same model (bug #7125)
-
+# Creation using keyword argument should cache the related object.
+>>> p = Parent.objects.get(name="Parent")
+>>> c = Child(parent=p)
+>>> c.parent is p
+True
+
+# Creation using keyword argument and unsaved related instance (#8070).
+>>> p = Parent()
+>>> c = Child(parent=p)
+>>> c.parent is p
+True
+
+# Creation using attname keyword argument and an id will cause the related
+# object to be fetched.
+>>> p = Parent.objects.get(name="Parent")
+>>> c = Child(parent_id=p.id)
+>>> c.parent is p
+False
+>>> c.parent == p
+True
+
+
+#
+# Test of multiple ForeignKeys to the same model (bug #7125).
+#
 >>> c1 = Category.objects.create(name='First')
 >>> c2 = Category.objects.create(name='Second')
 >>> c3 = Category.objects.create(name='Third')

tests/regressiontests/one_to_one_regress/models.py

@@ -88 +88 @@
     ...
 ValueError: Cannot assign "<Place: Demon Dogs the place>": "Place.restaurant" must be a "Restaurant" instance.
 
+# Creation using keyword argument should cache the related object.
+>>> p = Place.objects.get(name="Demon Dogs")
+>>> r = Restaurant(place=p)
+>>> r.place is p
+True
+
+# Creation using keyword argument and unsaved related instance (#8070).
+>>> p = Place()
+>>> r = Restaurant(place=p)
+>>> r.place is p
+True
+
+# Creation using attname keyword argument and an id will cause the related
+# object to be fetched.
+>>> p = Place.objects.get(name="Demon Dogs")
+>>> r = Restaurant(place_id=p.id)
+>>> r.place is p
+False
+>>> r.place == p
+True
+
 """}