Fixed #35275 -- Fixed Meta.constraints validation crash on UniqueConstraint with OpClass().

This also introduces Expression.constraint_validation_compatible that
allows specifying that expression should be ignored during a constraint
validation.

1 files changed, 13 insertions, 0 deletions

diff --git a/tests/postgres_tests/test_constraints.py b/tests/postgres_tests/test_constraints.py
index b3de53efd7..3cc76cdcfe 100644
--- a/tests/postgres_tests/test_constraints.py
+++ b/tests/postgres_tests/test_constraints.py
@@ -266,6 +266,19 @@ class SchemaTests(PostgreSQLTestCase):
         self.assertNotIn(constraint.name, self.get_constraints(Scene._meta.db_table))
         Scene.objects.create(scene="ScEnE 10", setting="Sir Bedemir's Castle")
 
+    def test_opclass_func_validate_constraints(self):
+        constraint_name = "test_opclass_func_validate_constraints"
+        constraint = UniqueConstraint(
+            OpClass(Lower("scene"), name="text_pattern_ops"),
+            name="test_opclass_func_validate_constraints",
+        )
+        Scene.objects.create(scene="First scene")
+        # Non-unique scene.
+        msg = f"Constraint “{constraint_name}” is violated."
+        with self.assertRaisesMessage(ValidationError, msg):
+            constraint.validate(Scene, Scene(scene="first Scene"))
+        constraint.validate(Scene, Scene(scene="second Scene"))
+
 
 class ExclusionConstraintTests(PostgreSQLTestCase):
     def get_constraints(self, table):