Removed Manager.use_for_related_fields and Meta.manager_inheritance_from_future.

Per deprecation timeline. Refs ed0ff913.

django/db/migrations/state.py

 from __future__ import unicode_literals
 
 import copy
-import warnings
 from collections import OrderedDict
 from contextlib import contextmanager
 
@@ -14,7 +13,6 @@ from django.db.models.fields.related import RECURSIVE_RELATIONSHIP_CONSTANT
 from django.db.models.options import DEFAULT_NAMES, normalize_together
 from django.db.models.utils import make_model_tuple
 from django.utils import six
-from django.utils.deprecation import RemovedInDjango20Warning
 from django.utils.encoding import force_text
 from django.utils.functional import cached_property
 from django.utils.module_loading import import_string
@@ -604,18 +602,8 @@ class ModelState(object):
 
         # Restore managers
         body.update(self.construct_managers())
-
-        with warnings.catch_warnings():
-            warnings.filterwarnings(
-                "ignore", "Managers from concrete parents will soon qualify as default managers",
-                RemovedInDjango20Warning)
-
-            # Then, make a Model object (apps.register_model is called in __new__)
-            return type(
-                str(self.name),
-                bases,
-                body,
-            )
+        # Then, make a Model object (apps.register_model is called in __new__)
+        return type(str(self.name), bases, body)
 
     def get_field_by_name(self, name):
         for fname, field in self.fields:

django/db/models/base.py

@@ -29,7 +29,6 @@ from django.db.models.signals import (
 )
 from django.db.models.utils import make_model_tuple
 from django.utils import six
-from django.utils.deprecation import RemovedInDjango20Warning
 from django.utils.encoding import (
     force_str, force_text, python_2_unicode_compatible,
 )
@@ -358,7 +357,7 @@ class ModelBase(type):
         if get_absolute_url_override:
             setattr(cls, 'get_absolute_url', get_absolute_url_override)
 
-        if not opts.managers or cls._requires_legacy_default_manager():
+        if not opts.managers:
             if any(f.name == 'objects' for f in opts.fields):
                 raise ValueError(
                     "Model %s must specify a custom Manager, because it has a "
@@ -370,79 +369,6 @@ class ModelBase(type):
 
         class_prepared.send(sender=cls)
 
-    def _requires_legacy_default_manager(cls):  # RemovedInDjango20Warning
-        opts = cls._meta
-
-        if opts.manager_inheritance_from_future:
-            return False
-
-        future_default_manager = opts.default_manager
-
-        # Step 1: Locate a manager that would have been promoted
-        # to default manager with the legacy system.
-        for manager in opts.managers:
-            originating_model = manager._originating_model
-            if (cls is originating_model or cls._meta.proxy or
-                    originating_model._meta.abstract):
-
-                if manager is not cls._default_manager and not opts.default_manager_name:
-                    warnings.warn(
-                        "Managers from concrete parents will soon qualify as default "
-                        "managers if they appear before any other managers in the "
-                        "MRO. As a result, '{legacy_default_manager}' declared on "
-                        "'{legacy_default_manager_model}' will no longer be the "
-                        "default manager for '{model}' in favor of "
-                        "'{future_default_manager}' declared on "
-                        "'{future_default_manager_model}'. "
-                        "You can redeclare '{legacy_default_manager}' on '{cls}' "
-                        "to keep things the way they are or you can switch to the new "
-                        "behavior right away by setting "
-                        "`Meta.manager_inheritance_from_future` to `True`.".format(
-                            cls=cls.__name__,
-                            model=opts.label,
-                            legacy_default_manager=manager.name,
-                            legacy_default_manager_model=manager._originating_model._meta.label,
-                            future_default_manager=future_default_manager.name,
-                            future_default_manager_model=future_default_manager._originating_model._meta.label,
-                        ),
-                        RemovedInDjango20Warning, 2
-                    )
-
-                    opts.default_manager_name = manager.name
-                    opts._expire_cache()
-
-                break
-
-        # Step 2: Since there are managers but none of them qualified as
-        # default managers under the legacy system (meaning that there are
-        # managers from concrete parents that would be promoted under the
-        # new system), we need to create a new Manager instance for the
-        # 'objects' attribute as a deprecation shim.
-        else:
-            # If the "future" default manager was auto created there is no
-            # point warning the user since it's basically the same manager.
-            if not future_default_manager.auto_created:
-                warnings.warn(
-                    "Managers from concrete parents will soon qualify as "
-                    "default managers. As a result, the 'objects' manager "
-                    "won't be created (or recreated) automatically "
-                    "anymore on '{model}' and '{future_default_manager}' "
-                    "declared on '{future_default_manager_model}' will be "
-                    "promoted to default manager. You can declare "
-                    "explicitly `objects = models.Manager()` on '{cls}' "
-                    "to keep things the way they are or you can switch "
-                    "to the new behavior right away by setting "
-                    "`Meta.manager_inheritance_from_future` to `True`.".format(
-                        cls=cls.__name__,
-                        model=opts.label,
-                        future_default_manager=future_default_manager.name,
-                        future_default_manager_model=future_default_manager._originating_model._meta.label,
-                    ),
-                    RemovedInDjango20Warning, 2
-                )
-
-            return True
-
     @property
     def _base_manager(cls):
         return cls._meta.base_manager

django/db/models/fields/related_descriptors.py

@@ -65,13 +65,11 @@ and two directions (forward and reverse) for a total of six combinations.
 
 from __future__ import unicode_literals
 
-import warnings
 from operator import attrgetter
 
 from django.db import connections, router, transaction
 from django.db.models import Q, signals
 from django.db.models.query import QuerySet
-from django.utils.deprecation import RemovedInDjango20Warning
 from django.utils.functional import cached_property
 
 
@@ -107,20 +105,7 @@ class ForwardManyToOneDescriptor(object):
         return hasattr(instance, self.cache_name)
 
     def get_queryset(self, **hints):
-        related_model = self.field.remote_field.model
-
-        if getattr(related_model._default_manager, 'use_for_related_fields', False):
-            if not getattr(related_model._default_manager, 'silence_use_for_related_fields_deprecation', False):
-                warnings.warn(
-                    "use_for_related_fields is deprecated, instead "
-                    "set Meta.base_manager_name on '{}'.".format(related_model._meta.label),
-                    RemovedInDjango20Warning, 2
-                )
-            manager = related_model._default_manager
-        else:
-            manager = related_model._base_manager
-
-        return manager.db_manager(hints=hints).all()
+        return self.field.remote_field.model._base_manager.db_manager(hints=hints).all()
 
     def get_prefetch_queryset(self, instances, queryset=None):
         if queryset is None:
@@ -323,20 +308,7 @@ class ReverseOneToOneDescriptor(object):
         return hasattr(instance, self.cache_name)
 
     def get_queryset(self, **hints):
-        related_model = self.related.related_model
-
-        if getattr(related_model._default_manager, 'use_for_related_fields', False):
-            if not getattr(related_model._default_manager, 'silence_use_for_related_fields_deprecation', False):
-                warnings.warn(
-                    "use_for_related_fields is deprecated, instead "
-                    "set Meta.base_manager_name on '{}'.".format(related_model._meta.label),
-                    RemovedInDjango20Warning, 2
-                )
-            manager = related_model._default_manager
-        else:
-            manager = related_model._base_manager
-
-        return manager.db_manager(hints=hints).all()
+        return self.related.related_model._base_manager.db_manager(hints=hints).all()
 
     def get_prefetch_queryset(self, instances, queryset=None):
         if queryset is None:

django/db/models/options.py

@@ -17,9 +17,7 @@ from django.db.models.fields.related import OneToOneField
 from django.db.models.query_utils import PathInfo
 from django.utils import six
 from django.utils.datastructures import ImmutableList, OrderedSet
-from django.utils.deprecation import (
-    RemovedInDjango20Warning, RemovedInDjango21Warning,
-)
+from django.utils.deprecation import RemovedInDjango21Warning
 from django.utils.encoding import force_text, python_2_unicode_compatible
 from django.utils.functional import cached_property
 from django.utils.text import camel_case_to_spaces, format_lazy
@@ -41,7 +39,7 @@ DEFAULT_NAMES = (
     'auto_created', 'index_together', 'apps', 'default_permissions',
     'select_on_save', 'default_related_name', 'required_db_features',
     'required_db_vendor', 'base_manager_name', 'default_manager_name',
-    'manager_inheritance_from_future', 'indexes',
+    'indexes',
 )
 
 
@@ -87,7 +85,6 @@ class Options(object):
         self.local_fields = []
         self.local_many_to_many = []
         self.private_fields = []
-        self.manager_inheritance_from_future = False
         self.local_managers = []
         self.base_manager_name = None
         self.default_manager_name = None
@@ -375,10 +372,6 @@ class Options(object):
                 seen_managers.add(manager.name)
                 managers.append((depth, manager.creation_counter, manager))
 
-                # Used for deprecation of legacy manager inheritance,
-                # remove afterwards. (RemovedInDjango20Warning)
-                manager._originating_model = base
-
         return make_immutable_fields_list(
             "managers",
             (m[2] for m in sorted(managers)),
@@ -410,25 +403,6 @@ class Options(object):
                     )
                 )
 
-        # Deprecation shim for `use_for_related_fields`.
-        for i, base_manager_class in enumerate(self.default_manager.__class__.mro()):
-            if getattr(base_manager_class, 'use_for_related_fields', False):
-                if not getattr(base_manager_class, 'silence_use_for_related_fields_deprecation', False):
-                    warnings.warn(
-                        "use_for_related_fields is deprecated, instead "
-                        "set Meta.base_manager_name on '{}'.".format(self.model._meta.label),
-                        RemovedInDjango20Warning, 2
-                    )
-
-                if i == 0:
-                    manager = self.default_manager
-                else:
-                    manager = base_manager_class()
-                    manager.name = '_base_manager'
-                    manager.model = self.model
-
-                return manager
-
         manager = Manager()
         manager.name = '_base_manager'
         manager.model = self.model

docs/releases/2.0.txt

@@ -384,3 +384,9 @@ these features.
   removed.
 
 * The ``escape`` filter now uses ``django.utils.html.conditional_escape()``.
+
+* ``Manager.use_for_related_fields`` is removed.
+
+* Model ``Manager`` inheritance follows MRO inheritance rules. The requirement
+  to use ``Meta.manager_inheritance_from_future`` to opt-in to the behavior is
+  removed.

tests/managers_regress/models.py

@@ -118,9 +118,6 @@ class Child5(AbstractBase3):
 class Child6(Child4):
     value = models.IntegerField()
 
-    class Meta:
-        manager_inheritance_from_future = True
-
 
 class Child7(Parent):
     objects = models.Manager()

tests/many_to_one/tests.py

@@ -4,8 +4,7 @@ from copy import deepcopy
 from django.core.exceptions import FieldError, MultipleObjectsReturned
 from django.db import models, transaction
 from django.db.utils import IntegrityError
-from django.test import TestCase, ignore_warnings
-from django.utils.deprecation import RemovedInDjango20Warning
+from django.test import TestCase
 from django.utils.translation import ugettext_lazy
 
 from .models import (
@@ -577,7 +576,6 @@ class ManyToOneTests(TestCase):
         with self.assertNumQueries(1):
             self.assertEqual(th.child_set.count(), 0)
 
-    @ignore_warnings(category=RemovedInDjango20Warning)  # for use_for_related_fields deprecation
     def test_related_object(self):
         public_school = School.objects.create(is_public=True)
         public_student = Student.objects.create(school=public_school)
@@ -595,17 +593,6 @@ class ManyToOneTests(TestCase):
         # allow it.
         self.assertEqual(private_student.school, private_school)
 
-        # If the manager is marked "use_for_related_fields", it'll get used instead
-        # of the "bare" queryset. Usually you'd define this as a property on the class,
-        # but this approximates that in a way that's easier in tests.
-        School._default_manager.use_for_related_fields = True
-        try:
-            private_student = Student.objects.get(pk=private_student.pk)
-            with self.assertRaises(School.DoesNotExist):
-                private_student.school
-        finally:
-            School._default_manager.use_for_related_fields = False
-
         School._meta.base_manager_name = 'objects'
         School._meta._expire_cache()
         try:

tests/one_to_one/tests.py

 from __future__ import unicode_literals
 
 from django.db import IntegrityError, connection, transaction
-from django.test import TestCase, ignore_warnings
-from django.utils.deprecation import RemovedInDjango20Warning
+from django.test import TestCase
 
 from .models import (
     Bar, Director, Favorites, HiddenPointer, ManualPrimaryKey, MultiModel,
@@ -419,7 +418,6 @@ class OneToOneTests(TestCase):
             hasattr(Target, HiddenPointer._meta.get_field('target').remote_field.get_accessor_name())
         )
 
-    @ignore_warnings(category=RemovedInDjango20Warning)  # for use_for_related_fields deprecation
     def test_related_object(self):
         public_school = School.objects.create(is_public=True)
         public_director = Director.objects.create(school=public_school, is_temp=False)
@@ -452,25 +450,6 @@ class OneToOneTests(TestCase):
         # allow it.
         self.assertEqual(private_school.director, private_director)
 
-        # If the manager is marked "use_for_related_fields", it'll get used instead
-        # of the "bare" queryset. Usually you'd define this as a property on the class,
-        # but this approximates that in a way that's easier in tests.
-        School._default_manager.use_for_related_fields = True
-        try:
-            private_director = Director._base_manager.get(pk=private_director.pk)
-            with self.assertRaises(School.DoesNotExist):
-                private_director.school
-        finally:
-            School._default_manager.use_for_related_fields = False
-
-        Director._default_manager.use_for_related_fields = True
-        try:
-            private_school = School._base_manager.get(pk=private_school.pk)
-            with self.assertRaises(Director.DoesNotExist):
-                private_school.director
-        finally:
-            Director._default_manager.use_for_related_fields = False
-
         School._meta.base_manager_name = 'objects'
         School._meta._expire_cache()
         try:

tests/serializers/models/multi_table.py

@@ -17,6 +17,3 @@ class Parent(models.Model):
 
 class Child(Parent):
     child_data = models.CharField(max_length=30, unique=True)
-
-    class Meta:
-        manager_inheritance_from_future = True