Merge pull request #44 from melvinkcx/bugfixes/update_starlette_test_…

…cases

update Starlette-specific test cases for starlette>=0.24

tests/middleware/test_starlette.py

@@ -88,11 +88,15 @@ async def handle(self, event: Event) -> None:
     dummy_handler_1 = DummyHandler()
     dummy_handler_2 = DummyHandler()
 
-    _ = Starlette(middleware=[
+    _app = Starlette(middleware=[
         Middleware(EventHandlerASGIMiddleware,
                    handlers=[dummy_handler_1, dummy_handler_2],
                    middleware_id=middleware_id)])
 
+    # Starlette started building the middleware stack lazily since version 0.24
+    # Ref: https://github.com/encode/starlette/releases/tag/0.24.0
+    _app.build_middleware_stack()
+
     if middleware_id is None:
         with pytest.raises(LookupError, match=r"^<ContextVar name='fastapi_middleware_identifier' at"):
             dispatch(event_name="new event", payload={"id": "fail"}, middleware_id=middleware_id)