[1.7.x] Fixed #23611 -- update_or_create failing from a related manager

Added update_or_create to RelatedManager, ManyRelatedManager and
GenericRelatedObjectManager.
Added missing get_or_create to GenericRelatedObjectManager.

Conflicts:
	tests/generic_relations/tests.py
	tests/get_or_create/tests.py

Backport of ed37f7e979 from master

6 files changed, 159 insertions, 5 deletions

diff --git a/django/contrib/contenttypes/fields.py b/django/contrib/contenttypes/fields.py
index b70a947ddf..a25aa64cb9 100644
--- a/django/contrib/contenttypes/fields.py
+++ b/django/contrib/contenttypes/fields.py
@@ -523,6 +523,20 @@ def create_generic_related_manager(superclass):
             return super(GenericRelatedObjectManager, self).using(db).create(**kwargs)
         create.alters_data = True
 
+        def get_or_create(self, **kwargs):
+            kwargs[self.content_type_field_name] = self.content_type
+            kwargs[self.object_id_field_name] = self.pk_val
+            db = router.db_for_write(self.model, instance=self.instance)
+            return super(GenericRelatedObjectManager, self).using(db).get_or_create(**kwargs)
+        get_or_create.alters_data = True
+
+        def update_or_create(self, **kwargs):
+            kwargs[self.content_type_field_name] = self.content_type
+            kwargs[self.object_id_field_name] = self.pk_val
+            db = router.db_for_write(self.model, instance=self.instance)
+            return super(GenericRelatedObjectManager, self).using(db).update_or_create(**kwargs)
+        update_or_create.alters_data = True
+
     return GenericRelatedObjectManager
 
 
diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py
index 868f43090d..d87a9229ef 100644
--- a/django/db/models/fields/related.py
+++ b/django/db/models/fields/related.py
@@ -715,13 +715,17 @@ def create_foreign_related_manager(superclass, rel_field, rel_model):
         create.alters_data = True
 
         def get_or_create(self, **kwargs):
-            # Update kwargs with the related object that this
-            # ForeignRelatedObjectsDescriptor knows about.
             kwargs[rel_field.name] = self.instance
             db = router.db_for_write(self.model, instance=self.instance)
             return super(RelatedManager, self.db_manager(db)).get_or_create(**kwargs)
         get_or_create.alters_data = True
 
+        def update_or_create(self, **kwargs):
+            kwargs[rel_field.name] = self.instance
+            db = router.db_for_write(self.model, instance=self.instance)
+            return super(RelatedManager, self.db_manager(db)).update_or_create(**kwargs)
+        update_or_create.alters_data = True
+
         # remove() and clear() are only provided if the ForeignKey can have a value of null.
         if rel_field.null:
             def remove(self, *objs, **kwargs):
@@ -963,8 +967,7 @@ def create_many_related_manager(superclass, rel):
 
         def get_or_create(self, **kwargs):
             db = router.db_for_write(self.instance.__class__, instance=self.instance)
-            obj, created = \
-                super(ManyRelatedManager, self.db_manager(db)).get_or_create(**kwargs)
+            obj, created = super(ManyRelatedManager, self.db_manager(db)).get_or_create(**kwargs)
             # We only need to add() if created because if we got an object back
             # from get() then the relationship already exists.
             if created:
@@ -972,6 +975,16 @@ def create_many_related_manager(superclass, rel):
             return obj, created
         get_or_create.alters_data = True
 
+        def update_or_create(self, **kwargs):
+            db = router.db_for_write(self.instance.__class__, instance=self.instance)
+            obj, created = super(ManyRelatedManager, self.db_manager(db)).update_or_create(**kwargs)
+            # We only need to add() if created because if we got an object back
+            # from get() then the relationship already exists.
+            if created:
+                self.add(obj)
+            return obj, created
+        update_or_create.alters_data = True
+
         def _add_items(self, source_field_name, target_field_name, *objs):
             # source_field_name: the PK fieldname in join table for the source object
             # target_field_name: the PK fieldname in join table for the target object
diff --git a/docs/releases/1.7.1.txt b/docs/releases/1.7.1.txt
index 1604e75da8..6511074542 100644
--- a/docs/releases/1.7.1.txt
+++ b/docs/releases/1.7.1.txt
@@ -100,3 +100,6 @@ Bugfixes
 
 * Fixed ``UnicodeDecodeError`` crash in ``AdminEmailHandler`` with non-ASCII
   characters in the request (:ticket:`23593`).
+
+* Fixed missing ``get_or_create`` and ``update_or_create`` on related managers
+  causing ``IntegrityError`` (:ticket:`23611`).
diff --git a/tests/generic_relations/tests.py b/tests/generic_relations/tests.py
index 3e05bb7225..3508a1096b 100644
--- a/tests/generic_relations/tests.py
+++ b/tests/generic_relations/tests.py
@@ -309,6 +309,64 @@ class GenericRelationsTests(TestCase):
             TaggedItem.objects.get(content_object='')
 
 
+class GetOrCreateAndUpdateOrCreateTests(TestCase):
+    """
+    GenericRelationsTests has changed significantly on master, this
+    standalone TestCase is part of the backport for #23611.
+    """
+    def setUp(self):
+        self.bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
+        self.bacon.tags.create(tag="fatty")
+        self.bacon.tags.create(tag="salty")
+
+    def test_generic_update_or_create_when_created(self):
+        """
+        Should be able to use update_or_create from the generic related manager
+        to create a tag. Refs #23611.
+        """
+        count = self.bacon.tags.count()
+        tag, created = self.bacon.tags.update_or_create(tag='stinky')
+        self.assertTrue(created)
+        self.assertEqual(count + 1, self.bacon.tags.count())
+
+    def test_generic_update_or_create_when_updated(self):
+        """
+        Should be able to use update_or_create from the generic related manager
+        to update a tag. Refs #23611.
+        """
+        count = self.bacon.tags.count()
+        tag = self.bacon.tags.create(tag='stinky')
+        self.assertEqual(count + 1, self.bacon.tags.count())
+        tag, created = self.bacon.tags.update_or_create(defaults={'tag': 'juicy'}, id=tag.id)
+        self.assertFalse(created)
+        self.assertEqual(count + 1, self.bacon.tags.count())
+        self.assertEqual(tag.tag, 'juicy')
+
+    def test_generic_get_or_create_when_created(self):
+        """
+        Should be able to use get_or_create from the generic related manager
+        to create a tag. Refs #23611.
+        """
+        count = self.bacon.tags.count()
+        tag, created = self.bacon.tags.get_or_create(tag='stinky')
+        self.assertTrue(created)
+        self.assertEqual(count + 1, self.bacon.tags.count())
+
+    def test_generic_get_or_create_when_exists(self):
+        """
+        Should be able to use get_or_create from the generic related manager
+        to get a tag. Refs #23611.
+        """
+        count = self.bacon.tags.count()
+        tag = self.bacon.tags.create(tag="stinky")
+        self.assertEqual(count + 1, self.bacon.tags.count())
+        tag, created = self.bacon.tags.get_or_create(id=tag.id, defaults={'tag': 'juicy'})
+        self.assertFalse(created)
+        self.assertEqual(count + 1, self.bacon.tags.count())
+        # shouldn't had changed the tag
+        self.assertEqual(tag.tag, 'stinky')
+
+
 class CustomWidget(forms.TextInput):
     pass
 
diff --git a/tests/get_or_create/models.py b/tests/get_or_create/models.py
index 1a85de2e74..915243a9c6 100644
--- a/tests/get_or_create/models.py
+++ b/tests/get_or_create/models.py
@@ -42,3 +42,17 @@ class Tag(models.Model):
 class Thing(models.Model):
     name = models.CharField(max_length=256)
     tags = models.ManyToManyField(Tag)
+
+
+class Publisher(models.Model):
+    name = models.CharField(max_length=100)
+
+
+class Author(models.Model):
+    name = models.CharField(max_length=100)
+
+
+class Book(models.Model):
+    name = models.CharField(max_length=100)
+    authors = models.ManyToManyField(Author, related_name='books')
+    publisher = models.ForeignKey(Publisher, related_name='books', db_column="publisher_id_column")
diff --git a/tests/get_or_create/tests.py b/tests/get_or_create/tests.py
index 1ddb2447fe..3a9a5a5a42 100644
--- a/tests/get_or_create/tests.py
+++ b/tests/get_or_create/tests.py
@@ -8,7 +8,8 @@ from django.db import IntegrityError, DatabaseError
 from django.utils.encoding import DjangoUnicodeDecodeError
 from django.test import TestCase, TransactionTestCase
 
-from .models import DefaultPerson, Person, ManualPrimaryKeyTest, Profile, Tag, Thing
+from .models import (DefaultPerson, Person, ManualPrimaryKeyTest, Profile,
+    Tag, Thing, Publisher, Author, Book)
 
 
 class GetOrCreateTests(TestCase):
@@ -199,3 +200,54 @@ class UpdateOrCreateTests(TestCase):
         except IntegrityError:
             formatted_traceback = traceback.format_exc()
             self.assertIn('obj.save', formatted_traceback)
+
+    def test_create_with_related_manager(self):
+        """
+        Should be able to use update_or_create from the related manager to
+        create a book. Refs #23611.
+        """
+        p = Publisher.objects.create(name="Acme Publishing")
+        book, created = p.books.update_or_create(name="The Book of Ed & Fred")
+        self.assertTrue(created)
+        self.assertEqual(p.books.count(), 1)
+
+    def test_update_with_related_manager(self):
+        """
+        Should be able to use update_or_create from the related manager to
+        update a book. Refs #23611.
+        """
+        p = Publisher.objects.create(name="Acme Publishing")
+        book = Book.objects.create(name="The Book of Ed & Fred", publisher=p)
+        self.assertEqual(p.books.count(), 1)
+        name = "The Book of Django"
+        book, created = p.books.update_or_create(defaults={'name': name}, id=book.id)
+        self.assertFalse(created)
+        self.assertEqual(book.name, name)
+        self.assertEqual(p.books.count(), 1)
+
+    def test_create_with_many(self):
+        """
+        Should be able to use update_or_create from the m2m related manager to
+        create a book. Refs #23611.
+        """
+        p = Publisher.objects.create(name="Acme Publishing")
+        author = Author.objects.create(name="Ted")
+        book, created = author.books.update_or_create(name="The Book of Ed & Fred", publisher=p)
+        self.assertTrue(created)
+        self.assertEqual(author.books.count(), 1)
+
+    def test_update_with_many(self):
+        """
+        Should be able to use update_or_create from the m2m related manager to
+        update a book. Refs #23611.
+        """
+        p = Publisher.objects.create(name="Acme Publishing")
+        author = Author.objects.create(name="Ted")
+        book = Book.objects.create(name="The Book of Ed & Fred", publisher=p)
+        book.authors.add(author)
+        self.assertEqual(author.books.count(), 1)
+        name = "The Book of Django"
+        book, created = author.books.update_or_create(defaults={'name': name}, id=book.id)
+        self.assertFalse(created)
+        self.assertEqual(book.name, name)
+        self.assertEqual(author.books.count(), 1)