--- a/mercurial/dirstate.py Sun Mar 05 16:20:07 2017 -0800
+++ b/mercurial/dirstate.py Wed Mar 01 17:59:21 2017 -0800
@@ -1235,8 +1235,14 @@
# end of this transaction
tr.registertmp(filename, location='plain')
- self._opener.write(prefix + self._filename + suffix,
- self._opener.tryread(filename))
+ backupname = prefix + self._filename + suffix
+ assert backupname != filename
+ if self._opener.exists(backupname):
+ self._opener.unlink(backupname)
+ # hardlink backup is okay because _writedirstate is always called
+ # with an "atomictemp=True" file.
+ util.copyfile(self._opener.join(filename),
+ self._opener.join(backupname), hardlink=True)
def restorebackup(self, tr, suffix='', prefix=''):
'''Restore dirstate by backup file with suffix'''