diff -r 00d905a12bb6 -r 2664f536a97e mercurial/localrepo.py
--- a/mercurial/localrepo.py	Wed May 20 04:34:27 2015 +0900
+++ b/mercurial/localrepo.py	Wed May 20 04:34:27 2015 +0900
@@ -975,7 +975,7 @@
             """will run pre-closing hooks"""
             pending = lambda: tr.writepending() and self.root or ""
             reporef().hook('pretxnclose', throw=True, pending=pending,
-                           xnname=desc, **tr.hookargs)
+                           txnname=desc, **tr.hookargs)
 
         tr = transaction.transaction(rp, self.sopener, vfsmap,
                                      "journal",