Fixed #25534, Fixed #31639 -- Added support for transform references in expressions.

Thanks Mariusz Felisiak and Simon Charette for reviews.

1 files changed, 9 insertions, 4 deletions

diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index b7f8053cb1..93cc32ac3c 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -1610,6 +1610,8 @@ class Query(BaseExpression):
         # fields to the appropriate wrapped version.
 
         def final_transformer(field, alias):
+            if not self.alias_cols:
+                alias = None
             return field.get_col(alias)
 
         # Try resolving all the names as fields first. If there's an error,
@@ -1714,8 +1716,6 @@ class Query(BaseExpression):
         yield from (expr.alias for expr in cls._gen_cols(exprs))
 
     def resolve_ref(self, name, allow_joins=True, reuse=None, summarize=False):
-        if not allow_joins and LOOKUP_SEP in name:
-            raise FieldError("Joined field references are not permitted in this query")
         annotation = self.annotations.get(name)
         if annotation is not None:
             if not allow_joins:
@@ -1740,6 +1740,11 @@ class Query(BaseExpression):
                 return annotation
         else:
             field_list = name.split(LOOKUP_SEP)
+            annotation = self.annotations.get(field_list[0])
+            if annotation is not None:
+                for transform in field_list[1:]:
+                    annotation = self.try_transform(annotation, transform)
+                return annotation
             join_info = self.setup_joins(field_list, self.get_meta(), self.get_initial_alias(), can_reuse=reuse)
             targets, final_alias, join_list = self.trim_joins(join_info.targets, join_info.joins, join_info.path)
             if not allow_joins and len(join_list) > 1:
@@ -1749,10 +1754,10 @@ class Query(BaseExpression):
                                  "isn't supported")
             # Verify that the last lookup in name is a field or a transform:
             # transform_function() raises FieldError if not.
-            join_info.transform_function(targets[0], final_alias)
+            transform = join_info.transform_function(targets[0], final_alias)
             if reuse is not None:
                 reuse.update(join_list)
-            return self._get_col(targets[0], join_info.targets[0], join_list[-1])
+            return transform
 
     def split_exclude(self, filter_expr, can_reuse, names_with_path):
         """