Fix issue 829 -- error message is displaying wrong incorrect result.

diff --git a/tornado/web.py b/tornado/web.py
index eade230ef82c98120b9c8c37d02f64a2c5b375bb..363c97c44a9c36d3d6f8fc2c10074fdbbe79f669 100644 (file)
--- a/tornado/web.py
+++ b/tornado/web.py
@@ -1142,7 +1142,7 @@ class RequestHandler(object):
             elif isinstance(result, Future):
                 if result.done():
                     if result.result() is not None:
-                        raise ValueError('Expected None, got %r' % result)
+                        raise ValueError('Expected None, got %r' % result.result())
                     callback()
                 else:
                     # Delayed import of IOLoop because it's not available