Run all IOStream callbacks inside a NullContext so that exception

handlers are run in the right order.

diff --git a/tornado/iostream.py b/tornado/iostream.py
index 0a4fd8f75c68c7b622cef5cdd61154d21c8fd749..ef1288b0a4d82b7f4abb3c320d26d5662b8c7bc3 100644 (file)
--- a/tornado/iostream.py
+++ b/tornado/iostream.py
@@ -177,7 +177,10 @@ class IOStream(object):
 
     def _run_callback(self, callback, *args, **kwargs):
         try:
-            callback(*args, **kwargs)
+            # Use a NullContext to ensure that all StackContexts are run
+            # inside our blanket exception handler rather than outside.
+            with stack_context.NullContext():
+                callback(*args, **kwargs)
         except:
             logging.error("Uncaught exception, closing connection.",
                           exc_info=True)