--- a/mercurial/repository.py	Mon Jul 02 11:14:13 2018 -0700
+++ b/mercurial/repository.py	Wed Jul 04 12:12:49 2018 -0700
@@ -922,6 +922,12 @@
     def clearcaches():
         """Clear caches associated with this collection."""
 
+    def rev(node):
+        """Obtain the revision number for a binary node.
+
+        Raises ``error.LookupError`` if the node is not known.
+        """
+
 class completelocalrepository(interfaceutil.Interface):
     """Monolithic interface for local repositories.