--- a/mercurial/localrepo.py	Tue May 15 14:35:41 2018 +0200
+++ b/mercurial/localrepo.py	Tue May 22 11:20:55 2018 -0700
@@ -781,6 +781,7 @@
         return self._makedirstate()
 
     def _makedirstate(self):
+        """Extension point for wrapping the dirstate per-repo."""
         sparsematchfn = lambda: sparse.matcher(self)
 
         return dirstate.dirstate(self.vfs, self.ui, self.root,