Detect non async driver on engine creation

An error is raised when creating an async engine with an
incompatible dbapi. Before the error was raised only when
first using the engine.

Change-Id: I977952b4c03ae51f568749ad744c545197bcd887
Reference: #5920

1 files changed, 11 insertions, 1 deletions

diff --git a/test/ext/asyncio/test_engine_py3k.py b/test/ext/asyncio/test_engine_py3k.py
index 72d866882..512f0447f 100644
--- a/test/ext/asyncio/test_engine_py3k.py
+++ b/test/ext/asyncio/test_engine_py3k.py
@@ -1,6 +1,7 @@
 import asyncio
 
 from sqlalchemy import Column
+from sqlalchemy import create_engine
 from sqlalchemy import delete
 from sqlalchemy import event
 from sqlalchemy import exc
@@ -662,9 +663,18 @@ class AsyncResultTest(EngineFixture):
 
 
 class TextSyncDBAPI(fixtures.TestBase):
+    def test_sync_dbapi_raises(self):
+        with expect_raises_message(
+            exc.InvalidRequestError,
+            "The asyncio extension requires an async driver to be used.",
+        ):
+            create_async_engine("sqlite:///:memory:")
+
     @testing.fixture
     def async_engine(self):
-        return create_async_engine("sqlite:///:memory:")
+        engine = create_engine("sqlite:///:memory:", future=True)
+        engine.dialect.is_async = True
+        return _async_engine.AsyncEngine(engine)
 
     @async_test
     @combinations(