--- a/mercurial/dirstate.py Sat Jun 11 20:59:49 2016 +0200
+++ b/mercurial/dirstate.py Mon Jun 13 05:11:56 2016 +0900
@@ -1243,7 +1243,8 @@
self.invalidate()
filename = self._actualfilename(tr)
# using self._filename to avoid having "pending" in the backup filename
- self._opener.rename(prefix + self._filename + suffix, filename)
+ self._opener.rename(prefix + self._filename + suffix, filename,
+ checkambig=True)
def clearbackup(self, tr, suffix='', prefix=''):
'''Clear backup file with suffix'''