--- a/mercurial/context.py	Wed Sep 19 00:23:02 2018 -0400
+++ b/mercurial/context.py	Tue Jul 17 17:16:22 2018 -0700
@@ -1052,7 +1052,7 @@
 
         renamed = self._filelog.renamed(self._filenode)
         if not renamed:
-            return renamed
+            return None
 
         if self.rev() == self.linkrev():
             return renamed