diff -r 6614b301ea58 -r e41a164db7a9 mercurial/revlog.py
--- a/mercurial/revlog.py	Wed Jan 15 15:50:04 2020 +0100
+++ b/mercurial/revlog.py	Wed Jan 15 15:50:14 2020 +0100
@@ -639,7 +639,7 @@
             if use_nodemap:
                 nodemap_data = nodemaputil.persisted_data(self)
                 if nodemap_data is not None:
-                    index.update_nodemap_data(nodemap_data[1])
+                    index.update_nodemap_data(*nodemap_data)
         except (ValueError, IndexError):
             raise error.RevlogError(
                 _(b"index %s is corrupted") % self.indexfile