diff -r 8197b395710e -r 4aa72cdf616f mercurial/bundlerepo.py
--- a/mercurial/bundlerepo.py	Tue Oct 08 19:35:30 2019 -0700
+++ b/mercurial/bundlerepo.py	Sun Oct 06 20:17:41 2019 -0700
@@ -212,7 +212,7 @@
 class bundlephasecache(phases.phasecache):
     def __init__(self, *args, **kwargs):
         super(bundlephasecache, self).__init__(*args, **kwargs)
-        if util.safehasattr(self, b'opener'):
+        if util.safehasattr(self, 'opener'):
             self.opener = vfsmod.readonlyvfs(self.opener)
 
     def write(self):