mercurial/dispatch.py

--- a/mercurial/dispatch.py	Thu Sep 10 10:50:03 2015 -0400
+++ b/mercurial/dispatch.py	Sun Sep 13 16:30:21 2015 -0400
@@ -181,7 +181,7 @@
                     debugtrace[debugger] == debugtrace['pdb']):
                     ui.warn(_("%s debugger specified "
                               "but its module was not found\n") % debugger)
-                with demandimport.disabled():
+                with demandimport.deactivated():
                     debugtrace[debugger]()
             try:
                 return _dispatch(req)