Ticket #36109: filteredrelation_stack.diff

django/db/models/sql/query.py

@@ -1922 +1922 @@
             reuse = can_reuse if join.m2m else None
             alias = self.join(connection, reuse=reuse)
             joins.append(alias)
+            if join.filtered_relation and can_reuse is not None:
+                can_reuse.add(alias)
         return JoinInfo(final_field, targets, opts, joins, path, final_transformer)
 
     def trim_joins(self, targets, joins, path):

tests/filtered_relation/tests.py

@@ -582 +582 @@
             lambda x: (x.author, x.book_title, x.preferred_by_author_pk),
         )
 
+    def test_three_level_nested_chained_relations(self):
+        borrower1 = Borrower.objects.create(name="Jenny")
+        # borrower 1 reserves, rents, and returns book1.
+        Reservation.objects.create(
+            borrower=borrower1,
+            book=self.book1,
+            state=Reservation.STOPPED,
+        )
+        qs = (
+            Author.objects.annotate(
+                my_books=FilteredRelation(
+                    "book"
+                ),
+                my_reserved_books=FilteredRelation(
+                    "my_books__reservation",
+                    condition=Q(my_books__reservation__state=Reservation.STOPPED)
+                ),
+                my_readers=FilteredRelation(
+                    "my_reserved_books__borrower",
+                    condition=Q(my_reserved_books__borrower=borrower1)
+                )
+            )
+        )
+
+        qs = qs.filter(
+            my_readers=borrower1
+        )
+        self.assertQuerySetEqual(
+            qs,
+            [
+                ("Alice",)
+            ],
+            lambda x: (x.name,),
+        )
+
+
     def test_deep_nested_foreign_key(self):
         qs = (
             Book.objects.annotate(