Refs #32096 -- Fixed ExpressionWrapper crash with JSONField key transforms.

Regression in 6789ded0a6.

Thanks Simon Charette and Igor Jerosimić for the report.

django/db/models/expressions.py

@@ -920,7 +920,7 @@ class ExpressionWrapper(Expression):
         return expression.get_group_by_cols(alias=alias)
 
     def as_sql(self, compiler, connection):
-        return self.expression.as_sql(compiler, connection)
+        return compiler.compile(self.expression)
 
     def __repr__(self):
         return "{}({})".format(self.__class__.__name__, self.expression)

docs/releases/3.1.3.txt

@@ -30,3 +30,7 @@ Bugfixes
 * Fixed a regression in Django 3.1 that caused a crash of ``__in`` lookup when
   using key transforms for :class:`~django.db.models.JSONField` in the lookup
   value (:ticket:`32096`).
+
+* Fixed a regression in Django 3.1 that caused a crash of
+  :class:`~django.db.models.ExpressionWrapper` with key transforms for
+  :class:`~django.db.models.JSONField` (:ticket:`32096`).

tests/model_fields/test_jsonfield.py

@@ -10,7 +10,10 @@ from django.db import (
     DataError, IntegrityError, NotSupportedError, OperationalError, connection,
     models,
 )
-from django.db.models import Count, F, OuterRef, Q, Subquery, Transform, Value
+from django.db.models import (
+    Count, ExpressionWrapper, F, IntegerField, OuterRef, Q, Subquery,
+    Transform, Value,
+)
 from django.db.models.expressions import RawSQL
 from django.db.models.fields.json import (
     KeyTextTransform, KeyTransform, KeyTransformFactory,
@@ -405,6 +408,17 @@ class TestQuerying(TestCase):
             [self.objs[4]],
         )
 
+    def test_expression_wrapper_key_transform(self):
+        self.assertSequenceEqual(
+            NullableJSONModel.objects.annotate(
+                expr=ExpressionWrapper(
+                    KeyTransform('c', 'value'),
+                    output_field=IntegerField(),
+                ),
+            ).filter(expr__isnull=False),
+            self.objs[3:5],
+        )
+
     def test_has_key(self):
         self.assertSequenceEqual(
             NullableJSONModel.objects.filter(value__has_key='a'),