mercurial/localrepo.py

--- a/mercurial/localrepo.py	Tue Oct 16 08:20:03 2018 +0200
+++ b/mercurial/localrepo.py	Tue Oct 16 08:29:24 2018 +0200
@@ -2047,9 +2047,9 @@
 
     def invalidatecaches(self):
 
-        if '_tagscache' in vars(self):
+        if r'_tagscache' in vars(self):
             # can't use delattr on proxy
-            del self.__dict__['_tagscache']
+            del self.__dict__[r'_tagscache']
 
         self.unfiltered()._branchcaches.clear()
         self.invalidatevolatilesets()