Fixed #28408 -- Added error message when updating with annotated expressions on joined fields.

Co-Authored-By: Simon Charette <charette.s@gmail.com>

django/db/models/sql/query.py

@@ -1613,10 +1613,26 @@ class Query(BaseExpression):
             self.unref_alias(joins.pop())
         return targets, joins[-1], joins
 
+    @classmethod
+    def _gen_col_aliases(cls, exprs):
+        for expr in exprs:
+            if isinstance(expr, Col):
+                yield expr.alias
+            else:
+                yield from cls._gen_col_aliases(expr.get_source_expressions())
+
     def resolve_ref(self, name, allow_joins=True, reuse=None, summarize=False, simple_col=False):
         if not allow_joins and LOOKUP_SEP in name:
             raise FieldError("Joined field references are not permitted in this query")
-        if name in self.annotations:
+        annotation = self.annotations.get(name)
+        if annotation is not None:
+            if not allow_joins:
+                for alias in self._gen_col_aliases([annotation]):
+                    if isinstance(self.alias_map[alias], Join):
+                        raise FieldError(
+                            'Joined field references are not permitted in '
+                            'this query'
+                        )
             if summarize:
                 # Summarize currently means we are doing an aggregate() query
                 # which is executed as a wrapped subquery if any of the
@@ -1624,7 +1640,7 @@ class Query(BaseExpression):
                 # that case we need to return a Ref to the subquery's annotation.
                 return Ref(name, self.annotation_select[name])
             else:
-                return self.annotations[name]
+                return annotation
         else:
             field_list = name.split(LOOKUP_SEP)
             join_info = self.setup_joins(field_list, self.get_meta(), self.get_initial_alias(), can_reuse=reuse)

tests/update/tests.py

@@ -1,5 +1,6 @@
 from django.core.exceptions import FieldError
 from django.db.models import Count, F, Max
+from django.db.models.functions import Concat, Lower
 from django.test import TestCase
 
 from .models import A, B, Bar, D, DataPoint, Foo, RelatedPoint
@@ -182,16 +183,19 @@ class AdvancedTests(TestCase):
         # Update where annotation is used for filtering
         qs = DataPoint.objects.annotate(related_count=Count('relatedpoint'))
         self.assertEqual(qs.filter(related_count=1).update(value='Foo'), 1)
-        # Update where annotation is used in update parameters
-        # #26539 - This isn't forbidden but also doesn't generate proper SQL
-        # qs = RelatedPoint.objects.annotate(data_name=F('data__name'))
-        # updated = qs.update(name=F('data_name'))
-        # self.assertEqual(updated, 1)
         # Update where aggregation annotation is used in update parameters
         qs = RelatedPoint.objects.annotate(max=Max('data__value'))
-        msg = (
+        msg = 'Joined field references are not permitted in this query'
-            'Aggregate functions are not allowed in this query '
-            '(name=Max(Col(update_datapoint, update.DataPoint.value))).'
-        )
         with self.assertRaisesMessage(FieldError, msg):
             qs.update(name=F('max'))
+
+    def test_update_with_joined_field_annotation(self):
+        msg = 'Joined field references are not permitted in this query'
+        for annotation in (
+            F('data__name'),
+            Lower('data__name'),
+            Concat('data__name', 'data__value'),
+        ):
+            with self.subTest(annotation=annotation):
+                with self.assertRaisesMessage(FieldError, msg):
+                    RelatedPoint.objects.annotate(new_name=annotation).update(name=F('new_name'))