diff --git a/mercurial/branchmap.py b/mercurial/branchmap.py
index 58d785679e158dcf460df8cffc32b7be4b36ea83_bWVyY3VyaWFsL2JyYW5jaG1hcC5weQ==..d99a588d8515ee07a5e2ddb9e715fb8c6cc45b38_bWVyY3VyaWFsL2JyYW5jaG1hcC5weQ== 100644
--- a/mercurial/branchmap.py
+++ b/mercurial/branchmap.py
@@ -480,7 +480,7 @@
         #   self.branchinfo = self._branchinfo
         #
         # Since we now have data in the cache, we need to drop this bypassing.
-        if 'branchinfo' in vars(self):
+        if r'branchinfo' in vars(self):
             del self.branchinfo
 
     def _setcachedata(self, rev, node, branchidx):