Fixed #29391 -- Made PostgresSimpleLookup respect Field.get_db_prep_value().

tests/postgres_tests/test_array.py

@@ -1,4 +1,5 @@
 import decimal
+import enum
 import json
 import unittest
 import uuid
@@ -16,9 +17,9 @@ from . import (
     PostgreSQLSimpleTestCase, PostgreSQLTestCase, PostgreSQLWidgetTestCase,
 )
 from .models import (
-    ArrayFieldSubclass, CharArrayModel, DateTimeArrayModel, IntegerArrayModel,
-    NestedIntegerArrayModel, NullableIntegerArrayModel, OtherTypesArrayModel,
-    PostgreSQLModel, Tag,
+    ArrayEnumModel, ArrayFieldSubclass, CharArrayModel, DateTimeArrayModel,
+    IntegerArrayModel, NestedIntegerArrayModel, NullableIntegerArrayModel,
+    OtherTypesArrayModel, PostgreSQLModel, Tag,
 )
 
 try:
@@ -357,6 +358,16 @@ class TestQuerying(PostgreSQLTestCase):
             [self.objs[3]]
         )
 
+    def test_enum_lookup(self):
+        class TestEnum(enum.Enum):
+            VALUE_1 = 'value_1'
+
+        instance = ArrayEnumModel.objects.create(array_of_enums=[TestEnum.VALUE_1])
+        self.assertSequenceEqual(
+            ArrayEnumModel.objects.filter(array_of_enums__contains=[TestEnum.VALUE_1]),
+            [instance]
+        )
+
     def test_unsupported_lookup(self):
         msg = "Unsupported lookup '0_bar' for ArrayField or join on the field not permitted."
         with self.assertRaisesMessage(FieldError, msg):