diff -r 75e8e16ca107 -r f0203c3406e7 mercurial/branchmap.py
--- a/mercurial/branchmap.py	Tue Apr 16 15:01:33 2019 +0300
+++ b/mercurial/branchmap.py	Mon Apr 15 19:21:41 2019 +0300
@@ -219,8 +219,9 @@
         return key in self._entries
 
     def iteritems(self):
-        self._verifyall()
-        return self._entries.iteritems()
+        for k, v in self._entries.iteritems():
+            self._verifybranch(k)
+            yield k, v
 
     def hasbranch(self, label):
         """ checks whether a branch of this name exists or not """