# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@octobus.net>
# Date 1623193184 -7200
# Node ID 88439c6fbafc77321c71c5a92c4642d422ffb471
# Parent  d2e0226b511a0ae37a4b315793f4ee3412e02cba
transaction: simplify `undo.backupfiles` file creation with a variable

This make the code shorter and clearer.

(This is an opportunity improvement while looking at something next to that.)

Differential Revision: https://phab.mercurial-scm.org/D10846

diff -r d2e0226b511a -r 88439c6fbafc mercurial/transaction.py
--- a/mercurial/transaction.py	Wed Jun 09 00:59:04 2021 +0200
+++ b/mercurial/transaction.py	Wed Jun 09 00:59:44 2021 +0200
@@ -633,9 +633,9 @@
         """write transaction data for possible future undo call"""
         if self._undoname is None:
             return
-        undobackupfile = self._opener.open(
-            b"%s.backupfiles" % self._undoname, b'w'
-        )
+
+        undo_backup_path = b"%s.backupfiles" % self._undoname
+        undobackupfile = self._opener.open(undo_backup_path, b'w')
         undobackupfile.write(b'%d\n' % version)
         for l, f, b, c in self._backupentries:
             if not f:  # temporary file