try to register engine

Author: fgregg

pytest_flask_sqlalchemy/fixtures.py

@@ -107,6 +107,7 @@ def _engine(pytestconfig, request, _transaction, mocker):
 
     # Calls to execution_options should return this mocked engine
     engine.execution_options.return_value = engine
+    sa.inspection._self_inspects(engine)
 
     # References to `Engine.dialect` should redirect to the Connection (this
     # is primarily useful for the `autoload` flag in SQLAlchemy, which references