mercurial/branchmap.py

--- a/mercurial/branchmap.py	Tue Apr 16 14:48:48 2019 +0300
+++ b/mercurial/branchmap.py	Tue Apr 16 15:01:33 2019 +0300
@@ -200,7 +200,8 @@
 
     def _verifyall(self):
         """ verifies nodes of all the branches """
-        for b in self._entries:
+        needverification = set(self._entries.keys()) - self._verifiedbranches
+        for b in needverification:
             self._verifybranch(b)
 
     def __iter__(self):