# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 1415192784 0
# Node ID b04263c38a92c48847f0e6c195bbf09ab9c047d0
# Parent  6c1351352b6c7d90dcb280f03ed73af7186f080f
transaction: extract backupentry registration in a dedicated function

We are about to use the 'backupentry' mechanism to allow cleaning up
transaction-related temporary files (such as 'changelog.i.a'). We start
by extracting the entry registration into its own method for easy reuse.

At that point, I would like to rename the backup-file related variable to
something generic but I'm a bit short of ideas.

diff -r 6c1351352b6c -r b04263c38a92 mercurial/transaction.py
--- a/mercurial/transaction.py	Sat Nov 08 16:35:15 2014 +0000
+++ b/mercurial/transaction.py	Wed Nov 05 13:06:24 2014 +0000
@@ -190,9 +190,13 @@
         else:
             backupfile = ''
 
-        self._backupentries.append((file, backupfile))
+        self._addbackupentry((file, backupfile))
+
+    def _addbackupentry(self, entry):
+        """register a new backup entry and write it to disk"""
+        self._backupentries.append(entry)
         self._backupmap[file] = len(self._backupentries) - 1
-        self._backupsfile.write("%s\0%s\n" % (file, backupfile))
+        self._backupsfile.write("%s\0%s\n" % entry)
         self._backupsfile.flush()
 
     @active