Support TypeDecorator.get_dbapi_type() for setinpusizes

Adjusted the "setinputsizes" logic relied upon by the cx_Oracle, asyncpg
and pg8000 dialects to support a :class:`.TypeDecorator` that includes
an override the :meth:`.TypeDecorator.get_dbapi_type()` method.

Change-Id: I5aa70abf0d9a9e2ca43309f2dd80b3fcd83881b9

1 files changed, 5 insertions, 3 deletions

diff --git a/test/orm/test_lazy_relations.py b/test/orm/test_lazy_relations.py
index e8da84841..c81de142c 100644
--- a/test/orm/test_lazy_relations.py
+++ b/test/orm/test_lazy_relations.py
@@ -1453,17 +1453,19 @@ class RefersToSelfLazyLoadInterferenceTest(fixtures.MappedTest):
 class TypeCoerceTest(fixtures.MappedTest, testing.AssertsExecutionResults):
     """ORM-level test for [ticket:3531]"""
 
-    # mysql is having a recursion issue in the bind_expression
-    __only_on__ = ("sqlite", "postgresql")
+    __backend__ = True
 
     class StringAsInt(TypeDecorator):
         impl = String(50)
 
+        def get_dbapi_type(self, dbapi):
+            return dbapi.NUMBER
+
         def column_expression(self, col):
             return sa.cast(col, Integer)
 
         def bind_expression(self, col):
-            return sa.cast(col, String)
+            return sa.cast(col, String(50))
 
     @classmethod
     def define_tables(cls, metadata):