Change logic to support when current_app is not available

flask/wrappers.py

@@ -174,9 +174,10 @@ class Request(RequestBase):
 
         .. versionadded:: 0.8
         """
-        if current_app.config['DEBUG']:
+        ctx = _request_ctx_stack.top
+        if ctx is not None:
+            if ctx.app.config.get('DEBUG', False):
                 raise BadRequest(e)
-        else:
         raise BadRequest()
 
     def _load_form_data(self):