diff -r 59a870a4ad6e -r 6a917075535a mercurial/manifest.py
--- a/mercurial/manifest.py	Tue Oct 09 22:02:01 2018 +0200
+++ b/mercurial/manifest.py	Tue Oct 09 23:26:35 2018 +0200
@@ -1575,11 +1575,11 @@
 
     def emitrevisions(self, nodes, nodesorder=None,
                       revisiondata=False, assumehaveparentrevisions=False,
-                      deltaprevious=False):
+                      deltamode=repository.CG_DELTAMODE_STD):
         return self._revlog.emitrevisions(
             nodes, nodesorder=nodesorder, revisiondata=revisiondata,
             assumehaveparentrevisions=assumehaveparentrevisions,
-            deltaprevious=deltaprevious)
+            deltamode=deltamode)
 
     def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None):
         return self._revlog.addgroup(deltas, linkmapper, transaction,