[3.1.x] Fixed #31651 -- Made ExpressionWrapper use grouping columns from wrapped expression.

Backport of df32fd42b84cc6dbba173201f244491b0d154a63 from master

2 files changed, 13 insertions, 0 deletions

diff --git a/django/db/models/expressions.py b/django/db/models/expressions.py
index 89332699d5..d728cab049 100644
--- a/django/db/models/expressions.py
+++ b/django/db/models/expressions.py
@@ -863,6 +863,9 @@ class ExpressionWrapper(Expression):
     def get_source_expressions(self):
         return [self.expression]
 
+    def get_group_by_cols(self, alias=None):
+        return self.expression.get_group_by_cols(alias=alias)
+
     def as_sql(self, compiler, connection):
         return self.expression.as_sql(compiler, connection)
 
diff --git a/tests/expressions/tests.py b/tests/expressions/tests.py
index 72bca4f205..57e4c8ebc7 100644
--- a/tests/expressions/tests.py
+++ b/tests/expressions/tests.py
@@ -1828,3 +1828,13 @@ class CombinableTests(SimpleTestCase):
     def test_reversed_or(self):
         with self.assertRaisesMessage(NotImplementedError, self.bitwise_msg):
             object() | Combinable()
+
+
+class ExpressionWrapperTests(SimpleTestCase):
+    def test_empty_group_by(self):
+        expr = ExpressionWrapper(Value(3), output_field=IntegerField())
+        self.assertEqual(expr.get_group_by_cols(alias=None), [])
+
+    def test_non_empty_group_by(self):
+        expr = ExpressionWrapper(Lower(Value('f')), output_field=IntegerField())
+        self.assertEqual(expr.get_group_by_cols(alias=None), [expr.expression])