- add migration notes for [ticket:2838]

- have TypeDecorator use process_bind_param for literal values if no
process_literal_param is set

1 files changed, 16 insertions, 0 deletions

diff --git a/test/sql/test_types.py b/test/sql/test_types.py
index 30a00ca56..7fc5dc35c 100644
--- a/test/sql/test_types.py
+++ b/test/sql/test_types.py
@@ -287,6 +287,22 @@ class UserDefinedTest(fixtures.TablesTest, AssertsCompiledSQL):
             literal_binds=True
         )
 
+    def test_typedecorator_literal_render_fallback_bound(self):
+        # fall back to process_bind_param for literal
+        # value rendering.
+        class MyType(types.TypeDecorator):
+            impl = String
+
+            def process_bind_param(self, value, dialect):
+                return "HI->%s<-THERE" % value
+
+        self.assert_compile(
+            select([literal("test", MyType)]),
+            "SELECT 'HI->test<-THERE' AS anon_1",
+            dialect='default',
+            literal_binds=True
+        )
+
     def test_typedecorator_impl(self):
         for impl_, exp, kw in [
             (Float, "FLOAT", {}),