Ticket #10811: 10811-2.patch

django/db/models/fields/related.py

@@ -331 +331 @@
                 if not router.allow_relation(value, instance):
                     raise ValueError('Cannot assign "%r": the current database router prevents this relation.' % value)
 
+            pk = tuple(getattr(value, field.attname, None) for _, field in self.field.related_fields)
+            if None in pk and self.field.null is False:
+                raise ValueError('Cannot assign "%r": "%s" instance isn\'t saved in the database.' %
+                                    (value, self.field.rel.to._meta.object_name))
+
         # If we're setting the value of a OneToOneField to None, we need to clear
         # out the cache on any old related object. Otherwise, deleting the
         # previously-related object will also cause this object to be deleted,
@@ -352 +357 @@
 
         # Set the value of the related field
         for lh_field, rh_field in self.field.related_fields:
-            try:
-                setattr(instance, lh_field.attname, getattr(value, rh_field.attname))
-            except AttributeError:
-                setattr(instance, lh_field.attname, None)
+            setattr(instance, lh_field.attname, getattr(value, rh_field.attname, None))
 
         # Since we already know what the related object is, seed the related
         # object caches now, too. This avoids another db hit if you get the

tests/admin_util/tests.py

@@ -100 +100 @@
         simple_function = lambda obj: SIMPLE_FUNCTION
 
         article = Article(
-            site=Site(domain=SITE_NAME),
+            site=Site.objects.create(domain=SITE_NAME),
             title=TITLE_TEXT,
             created=CREATED_DATE,
         )

tests/many_to_one_regress/tests.py

@@ -65 +65 @@
         c = Child(parent=p)
         self.assertTrue(c.parent is p)
 
-        # Creation using keyword argument and unsaved related instance (#8070).
-        p = Parent()
-        c = Child(parent=p)
-        self.assertTrue(c.parent is p)
-
         # Creation using attname keyword argument and an id will cause the
         # related object to be fetched.
         p = Parent.objects.get(name="Parent")

tests/model_formsets/tests.py

@@ -548 +548 @@
             'book_set-2-title': '',
         }
 
-        formset = AuthorBooksFormSet(data, instance=Author(), save_as_new=True)
+        new_author = Author.objects.create(name='Charles Baudelaire')
+
+        formset = AuthorBooksFormSet(data, instance=new_author, save_as_new=True)
         self.assertTrue(formset.is_valid())
 
-        new_author = Author.objects.create(name='Charles Baudelaire')
         formset = AuthorBooksFormSet(data, instance=new_author, save_as_new=True)
         saved = formset.save()
         self.assertEqual(len(saved), 2)

tests/model_regress/tests.py

@@ -6 +6 @@
 import unittest
 
 from django.core.exceptions import ValidationError
-from django.test import TestCase, skipUnlessDBFeature
-from django.utils import six
-from django.utils import tzinfo
 from django.db import connection, router
 from django.db.models.sql import InsertQuery
+from django.test import TestCase, skipUnlessDBFeature
+from django.utils import six, tzinfo
 
 from .models import (Worker, Article, Party, Event, Department,
     BrokenUnicodeMethod, NonAutoPK, Model1, Model2, Model3)
@@ -214 +213 @@
         m3 = Model3.objects.get(model2=1000)
         m3.model2
 
+    def test_assign_unsaved_instance_to_fk(self):
+        """
+        Regression for #10811: Can't assign an unsaved instance to a FK
+        """
+        w = Worker(name="Joe")
+        d = Department(name="Accounting")       # not saved in the database
+        with six.assertRaisesRegex(self, ValueError,
+                'Cannot assign "<Department: Accounting>": '
+                '"Department" instance isn\'t saved in the database.'):
+            w.department = d
+
 
 class ModelValidationTest(TestCase):
     def test_pk_validation(self):

tests/one_to_one_regress/tests.py

@@ -94 +94 @@
         r = Restaurant(place=p)
         self.assertTrue(r.place is p)
 
-        # Creation using keyword argument and unsaved related instance (#8070).
-        p = Place()
-        r = Restaurant(place=p)
-        self.assertTrue(r.place is p)
-
         # Creation using attname keyword argument and an id will cause the related
         # object to be fetched.
         p = Place.objects.get(name="Demon Dogs")