Revert addition of UpdateOrCreateMixin; reaches 100% test coverage.

CHANGES.rst

@@ -14,9 +14,6 @@ tip (unreleased)
 - Removed deprecated ``ChoiceEnum``, ``InheritanceCastModel``,
   ``InheritanceCastManager``, and ``manager_from``.
 
-- Added ``UpdateOrCreateMixin`` for custom queryset subclasses. Thanks Antti
-  Kaihola.
-
 - Fixed pickling of ``PassThroughManager``. Thanks Rinat Shigapov.
 
 - Set ``use_for_related_fields = True`` on ``QueryManager``.

README.rst

@@ -389,34 +389,3 @@ directly on the manager::
     Post.objects.by_author(user=request.user).unpublished()
 
 
-
-UpdateOrCreateMixin
-===================
-
-`Ticket #3182`_ in Django's bug tracker suggests
-an ``update_or_create()`` method for managers and querysets.
-The method works in a similar way as ``get_or_create()``,
-but in addition to returning an object if it's found in the database,
-it updates the object's fields according to the ``defaults`` keyword argument.
-
-.. _`Ticket #3182`: https://code.djangoproject.com/ticket/3182
-
-Use this mixin in a custom ``QuerySet`` subclass, and create a corresponding
-manager with ``PassThroughManager``::
-
-    from datetime import datetime
-    from django.db import models
-    from django.db.models.query import QuerySet
-    from model_utils.managers import UpdateOrCreateMixin
-    
-    class PostQuerySet(QuerySet, UpdateOrCreateMixin):
-        pass
-
-    class Post(models.Model):
-        user = models.ForeignKey(User)
-        published = models.DateTimeField()
-    
-        objects = PassThroughManager.for_queryset_class(PostQuerySet)()
-    
-    Post.objects.update_or_create(user=request.user,
-                                  defaults={'published': datetime.now()})

model_utils/managers.py

@@ -153,42 +153,3 @@ def create_pass_through_manager_for_queryset_class(base, queryset_cls):
 def unpickle_pass_through_manager_for_queryset_class(base, queryset_cls):
     cls = create_pass_through_manager_for_queryset_class(base, queryset_cls)
     return cls.__new__(cls)
-
-
-class UpdateOrCreateMixin(object):
-    def update_or_create(self, **kwargs):
-        """
-        Looks up an object with the given kwargs, creating one if necessary.
-        If the object already exists, then its fields are updated with the
-        values passed in the defaults dictionary.
-        Returns a tuple of (object, created), where created is a boolean
-        specifying whether an object was created.
-
-        See https://code.djangoproject.com/ticket/3182
-        """
-        assert kwargs, \
-            'update_or_create() must be passed at least one keyword argument'
-        defaults = kwargs.pop('defaults', {})
-        lookup = kwargs.copy()
-        for f in self.model._meta.fields:
-            if f.attname in lookup:
-                lookup[f.name] = lookup.pop(f.attname)
-        self._for_write = True
-        sid = transaction.savepoint(using=self.db)
-        try:
-            obj = self.get(**lookup)
-            create = False
-        except self.model.DoesNotExist:
-            params = dict([(k, v) for k, v in kwargs.items() if '__' not in k])
-            obj = self.model(**params)
-            create = True
-        for attname, value in defaults.items():
-            setattr(obj, attname, value)
-        try:
-            obj.save(force_insert=create, using=self.db)
-            transaction.savepoint_commit(sid, using=self.db)
-            return obj, create
-        except IntegrityError:
-            transaction.savepoint_rollback(sid, using=self.db)
-            exc_info = sys.exc_info()
-            raise exc_info[1], None, exc_info[2]

model_utils/tests/models.py

@@ -2,7 +2,7 @@ from django.db import models
 from django.utils.translation import ugettext_lazy as _
 
 from model_utils.models import TimeStampedModel, StatusModel, TimeFramedModel
-from model_utils.managers import QueryManager, InheritanceManager, PassThroughManager, UpdateOrCreateMixin
+from model_utils.managers import QueryManager, InheritanceManager, PassThroughManager
 from model_utils.fields import SplitField, MonitorField
 from model_utils import Choices
 
@@ -215,22 +215,3 @@ class Spot(models.Model):
     owner = models.ForeignKey(Dude, related_name='spots_owned')
 
     objects = PassThroughManager.for_queryset_class(SpotQuerySet)()
-
-
-class PersonQuerySet(models.query.QuerySet, UpdateOrCreateMixin):
-    pass
-
-
-class Person(models.Model):
-    first_name = models.CharField(max_length=100)
-    last_name = models.CharField(max_length=100)
-    birthday = models.DateField()
-
-    objects = PassThroughManager(PersonQuerySet)
-
-    def __str__(self):
-        return '%s %s, Birthday: %s' % (self.first_name, self.last_name,
-                                        self.birthday)
-
-    class Meta:
-        ordering = ('last_name',)

model_utils/tests/tests.py

@@ -2,7 +2,7 @@ from __future__ import with_statement
 
 import pickle
 
-from datetime import date, datetime, timedelta
+from datetime import datetime, timedelta
 
 from django.db import models
 from django.db.models.fields import FieldDoesNotExist
@@ -18,8 +18,7 @@ from model_utils.tests.models import (
     InheritanceManagerTestParent, InheritanceManagerTestChild1,
     InheritanceManagerTestChild2, TimeStamp, Post, Article, Status,
     StatusPlainTuple, TimeFrame, Monitored, StatusManagerAdded,
-    TimeFrameManagerAdded, Dude, SplitFieldAbstractParent, Car, Spot,
-    Person)
+    TimeFrameManagerAdded, Dude, SplitFieldAbstractParent, Car, Spot)
 
 
 
@@ -576,52 +575,3 @@ class CreatePassThroughManagerTests(TestCase):
         pickled_qs = pickle.dumps(qs)
         unpickled_qs = pickle.loads(pickled_qs)
         self.assertEqual(unpickled_qs.secured().count(), 1)
-
-
-class UpdateOrCreateTests(TestCase):
-    def test_update_or_create(self):
-        Person.objects.create(
-            first_name='John', last_name='Lennon', birthday=date(1940, 10, 9)
-        )
-
-        p, created = Person.objects.update_or_create(
-            first_name='John', last_name='Lennon', defaults={
-                'birthday': date(1970, 10, 9)
-            }
-        )
-        self.assertFalse(created)
-        self.assertEqual(Person.objects.count(), 1)
-        self.assertEqual(Person.objects.get().birthday, date(1970, 10, 9))
-
-        p, created = Person.objects.update_or_create(
-            first_name='George', last_name='Harrison', defaults={
-                'birthday': date(1943, 2, 25)
-            }
-        )
-        self.assertTrue(created)
-        self.assertEqual(Person.objects.count(), 2)
-
-        # If we execute the exact same statement, it won't create a Person.
-        p, created = Person.objects.update_or_create(
-            first_name='George', last_name='Harrison', defaults={
-                'birthday': date(1943, 2, 25)
-            }
-        )
-        self.assertFalse(created)
-        self.assertEqual(Person.objects.count(), 2)
-
-        # update_or_create() can take an empty 'defaults' parameter, but in
-        # this situation behaves exactly like get_or_create().  This is useful
-        # if you are building the 'defaults' dictionary dynamically.
-        p, created = Person.objects.update_or_create(
-            first_name='George', last_name='Harrison', defaults={}
-        )
-        self.assertFalse(created)
-
-        # A different name with an empty 'defaults'.
-        p, created = Person.objects.update_or_create(
-            first_name='John', last_name='Smith', birthday=date(1950, 2, 10),
-            defaults={}
-        )
-        self.assertTrue(created)
-        self.assertEqual(Person.objects.count(), 3)