From e37ab311fc52ff5c9ea0951ce3a8d8b38f285900 Mon Sep 17 00:00:00 2001
From: Markus Holtermann <info@markusholtermann.eu>
Date: Wed, 5 Nov 2014 19:53:16 +0100
Subject: [PATCH] Changed internal storing of abstract and concrete managers to
 be in a single list.

This commit prepares the internal manager layout to be serialized by
migrations; refs #23822.
---
 django/db/models/base.py    |  3 +--
 django/db/models/manager.py | 18 ++++++++----------
 django/db/models/options.py | 21 ++++++++++++++++++---
 3 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/django/db/models/base.py b/django/db/models/base.py
index c2f711ea08..af007d77ce 100644
--- a/django/db/models/base.py
+++ b/django/db/models/base.py
@@ -1225,8 +1225,7 @@ class Model(six.with_metaclass(ModelBase)):
         """ Perform all manager checks. """
 
         errors = []
-        managers = cls._meta.concrete_managers + cls._meta.abstract_managers
-        for __, __, manager in managers:
+        for __, manager, __ in cls._meta.managers:
             errors.extend(manager.check(**kwargs))
         return errors
 
diff --git a/django/db/models/manager.py b/django/db/models/manager.py
index 5510b7d438..3f459faf13 100644
--- a/django/db/models/manager.py
+++ b/django/db/models/manager.py
@@ -62,6 +62,7 @@ class BaseManager(object):
         super(BaseManager, self).__init__()
         self._set_creation_counter()
         self.model = None
+        self.name = None
         self._inherited = False
         self._db = None
         self._hints = {}
@@ -69,12 +70,8 @@ class BaseManager(object):
     def __str__(self):
         """ Return "app_label.model_label.manager_name". """
         model = self.model
-        opts = model._meta
         app = model._meta.app_label
-        manager_name = next(name for (_, name, manager)
-            in opts.concrete_managers + opts.abstract_managers
-            if manager == self)
-        return '%s.%s.%s' % (app, model._meta.object_name, manager_name)
+        return '%s.%s.%s' % (app, model._meta.object_name, self.name)
 
     def check(self, **kwargs):
         return []
@@ -116,6 +113,8 @@ class BaseManager(object):
     def contribute_to_class(self, model, name):
         # TODO: Use weakref because of possible memory leak / circular reference.
         self.model = model
+        if not self.name:
+            self.name = name
         # Only contribute the manager if the model is concrete
         if model._meta.abstract:
             setattr(model, name, AbstractManagerDescriptor(model))
@@ -127,12 +126,11 @@ class BaseManager(object):
         if (not getattr(model, '_default_manager', None) or
                 self.creation_counter < model._default_manager.creation_counter):
             model._default_manager = self
+
+        abstract = False
         if model._meta.abstract or (self._inherited and not self.model._meta.proxy):
-            model._meta.abstract_managers.append((self.creation_counter, name,
-                    self))
-        else:
-            model._meta.concrete_managers.append((self.creation_counter, name,
-                self))
+            abstract = True
+        model._meta.managers.append((self.creation_counter, self, abstract))
 
     def _set_creation_counter(self):
         """
diff --git a/django/db/models/options.py b/django/db/models/options.py
index 22fa8faf10..67010ef654 100644
--- a/django/db/models/options.py
+++ b/django/db/models/options.py
@@ -88,9 +88,10 @@ class Options(object):
         self.auto_created = False
 
         # To handle various inheritance situations, we need to track where
-        # managers came from (concrete or abstract base classes).
-        self.abstract_managers = []
-        self.concrete_managers = []
+        # managers came from (concrete or abstract base classes). `managers`
+        # keeps a list of 3-tuples of the form:
+        # (creation_counter, instance, abstract(=True))
+        self.managers = []
 
         # List of all lookups defined in ForeignKey 'limit_choices_to' options
         # from *other* models. Needed for some admin checks. Internal use only.
@@ -110,6 +111,20 @@ class Options(object):
     def installed(self):
         return self.app_config is not None
 
+    @property
+    def abstract_managers(self):
+        return [
+            (counter, instance.name, instance) for counter, instance, abstract
+            in self.managers if abstract
+        ]
+
+    @property
+    def concrete_managers(self):
+        return [
+            (counter, instance.name, instance) for counter, instance, abstract
+            in self.managers if not abstract
+        ]
+
     def contribute_to_class(self, cls, name):
         from django.db import connection
         from django.db.backends.utils import truncate_name