diff -r 8489e6f68ef2 -r a9ea2b1e5c4b mercurial/util.py
--- a/mercurial/util.py	Sat Mar 24 14:09:44 2018 +0900
+++ b/mercurial/util.py	Sat Mar 24 14:13:37 2018 +0900
@@ -1586,8 +1586,6 @@
     if buf:
         yield ''.join(buf)
 
-Abort = error.Abort
-
 def always(fn):
     return True