check for adapt to same class in AbstractRange

Fixed regression where newly revised PostgreSQL range types such as
:class:`_postgresql.INT4RANGE` could not be set up as the impl of a
:class:`.TypeDecorator` custom type, instead raising a ``TypeError``.

Fixes: #9020
Change-Id: Ib881c3c7f63d000f49a09185a8663659a9970aa9

1 files changed, 19 insertions, 0 deletions

diff --git a/test/dialect/postgresql/test_types.py b/test/dialect/postgresql/test_types.py
index caa758b0d..e9d5e561f 100644
--- a/test/dialect/postgresql/test_types.py
+++ b/test/dialect/postgresql/test_types.py
@@ -4486,6 +4486,25 @@ class _RangeTypeRoundTrip(_RangeComparisonFixtures, fixtures.TablesTest):
         cols = insp.get_columns("data_table")
         assert isinstance(cols[0]["type"], self._col_type)
 
+    def test_type_decorator_round_trip(self, connection, metadata):
+        """test #9020"""
+
+        class MyRange(TypeDecorator):
+            cache_ok = True
+            impl = self._col_type
+
+        table = Table(
+            "typedec_table",
+            metadata,
+            Column("range", MyRange, primary_key=True),
+        )
+        table.create(connection)
+        connection.execute(table.insert(), {"range": self._data_obj()})
+        data = connection.execute(
+            select(table.c.range).where(table.c.range == self._data_obj())
+        ).fetchall()
+        eq_(data, [(self._data_obj(),)])
+
     def test_textual_round_trip_w_dialect_type(self, connection):
         """test #8690"""
         data_table = self.tables.data_table