[1.8.x] Fixed #24156 -- Fixed inherited related name of ManyToManyField.

Fixed situation when parent abstract model declares related_name='+'
and child models had an invalid queryset.

Backport of f7b2978158 from master

django/db/models/fields/related.py

@@ -2540,7 +2540,7 @@ class ManyToManyField(RelatedField):
             # related_name with one generated from the m2m field name. Django
             # still uses backwards relations internally and we need to avoid
             # clashes between multiple m2m fields with related_name == '+'.
-            self.rel.related_name = "_%s_+" % name
+            self.rel.related_name = "_%s_%s_+" % (cls.__name__.lower(), name)
 
         super(ManyToManyField, self).contribute_to_class(cls, name, **kwargs)
 

docs/releases/1.8.6.txt

@@ -17,3 +17,7 @@ Bugfixes
 
 * Fixed system check crash on ``ForeignKey`` to abstract model
   (:ticket:`25503`).
+
+* Fixed incorrect queries when you have multiple ``ManyToManyField``\s on
+  different models that have the same field name, point to the same model, and
+  have their reverse relations disabled (:ticket:`25545`).

tests/many_to_many/models.py

@@ -35,3 +35,20 @@ class Article(models.Model):
 
     class Meta:
         ordering = ('headline',)
+
+
+# Models to test correct related_name inheritance
+class AbstractArticle(models.Model):
+    class Meta:
+        abstract = True
+        ordering = ('title',)
+
+    publications = models.ManyToManyField(Publication, name='publications', related_name='+')
+
+
+class InheritedArticleA(AbstractArticle):
+    pass
+
+
+class InheritedArticleB(AbstractArticle):
+    pass

tests/many_to_many/tests.py

@@ -4,7 +4,7 @@ from django.db import transaction
 from django.test import TestCase
 from django.utils import six
 
-from .models import Article, Publication
+from .models import Article, InheritedArticleA, InheritedArticleB, Publication
 
 
 class ManyToManyTests(TestCase):
@@ -415,3 +415,28 @@ class ManyToManyTests(TestCase):
         self.assertQuerysetEqual(self.a4.publications.all(), [])
         self.assertQuerysetEqual(self.p2.article_set.all(),
                                  ['<Article: NASA finds intelligent life on Earth>'])
+
+    def test_inherited_models_selects(self):
+        """
+        #24156 - Objects from child models where the parent's m2m field uses
+        related_name='+' should be retrieved correctly.
+        """
+        a = InheritedArticleA.objects.create()
+        b = InheritedArticleB.objects.create()
+        a.publications.add(self.p1, self.p2)
+        self.assertQuerysetEqual(a.publications.all(),
+            [
+                '<Publication: Science News>',
+                '<Publication: The Python Journal>',
+            ])
+        self.assertQuerysetEqual(b.publications.all(), [])
+        b.publications.add(self.p3)
+        self.assertQuerysetEqual(a.publications.all(),
+            [
+                '<Publication: Science News>',
+                '<Publication: The Python Journal>',
+            ])
+        self.assertQuerysetEqual(b.publications.all(),
+            [
+                '<Publication: Science Weekly>',
+            ])

tests/model_meta/results.py

@@ -319,7 +319,7 @@ TEST_RESULTS = {
     'get_all_related_objects_with_model_hidden_local': {
         Person: (
             ('+', None),
-            ('_people_hidden_+', None),
+            ('_relating_people_hidden_+', None),
             ('Person_following_inherited+', None),
             ('Person_following_inherited+', None),
             ('Person_friends_inherited+', None),
@@ -334,7 +334,7 @@ TEST_RESULTS = {
         ),
         BasePerson: (
             ('+', None),
-            ('_basepeople_hidden_+', None),
+            ('_relating_basepeople_hidden_+', None),
             ('BasePerson_following_abstract+', None),
             ('BasePerson_following_abstract+', None),
             ('BasePerson_following_base+', None),
@@ -382,8 +382,8 @@ TEST_RESULTS = {
         Person: (
             ('+', BasePerson),
             ('+', None),
-            ('_basepeople_hidden_+', BasePerson),
-            ('_people_hidden_+', None),
+            ('_relating_basepeople_hidden_+', BasePerson),
+            ('_relating_people_hidden_+', None),
             ('BasePerson_following_abstract+', BasePerson),
             ('BasePerson_following_abstract+', BasePerson),
             ('BasePerson_following_base+', BasePerson),
@@ -416,7 +416,7 @@ TEST_RESULTS = {
         ),
         BasePerson: (
             ('+', None),
-            ('_basepeople_hidden_+', None),
+            ('_relating_basepeople_hidden_+', None),
             ('BasePerson_following_abstract+', None),
             ('BasePerson_following_abstract+', None),
             ('BasePerson_following_base+', None),
@@ -730,7 +730,7 @@ TEST_RESULTS = {
             ('friends_base_rel_+', None),
             ('followers_base', None),
             ('relating_basepeople', None),
-            ('_basepeople_hidden_+', None),
+            ('_relating_basepeople_hidden_+', None),
         ),
         Person: (
             ('friends_abstract_rel_+', BasePerson),
@@ -738,11 +738,11 @@ TEST_RESULTS = {
             ('friends_base_rel_+', BasePerson),
             ('followers_base', BasePerson),
             ('relating_basepeople', BasePerson),
-            ('_basepeople_hidden_+', BasePerson),
+            ('_relating_basepeople_hidden_+', BasePerson),
             ('friends_inherited_rel_+', None),
             ('followers_concrete', None),
             ('relating_people', None),
-            ('_people_hidden_+', None),
+            ('_relating_people_hidden_+', None),
         ),
         Relation: (
             ('m2m_abstract_rel', None),
@@ -757,13 +757,13 @@ TEST_RESULTS = {
             'friends_base_rel_+',
             'followers_base',
             'relating_basepeople',
-            '_basepeople_hidden_+',
+            '_relating_basepeople_hidden_+',
         ],
         Person: [
             'friends_inherited_rel_+',
             'followers_concrete',
             'relating_people',
-            '_people_hidden_+',
+            '_relating_people_hidden_+',
         ],
         Relation: [
             'm2m_abstract_rel',

tests/model_meta/tests.py

@@ -237,7 +237,7 @@ class RelationTreeTests(TestCase):
         self.assertEqual(
             sorted([field.related_query_name() for field in BasePerson._meta._relation_tree]),
             sorted([
-                '+', '_basepeople_hidden_+', 'BasePerson_following_abstract+', 'BasePerson_following_abstract+',
+                '+', '_relating_basepeople_hidden_+', 'BasePerson_following_abstract+', 'BasePerson_following_abstract+',
                 'BasePerson_following_base+', 'BasePerson_following_base+', 'BasePerson_friends_abstract+',
                 'BasePerson_friends_abstract+', 'BasePerson_friends_base+', 'BasePerson_friends_base+',
                 'BasePerson_m2m_abstract+', 'BasePerson_m2m_base+', 'Relating_basepeople+',