--- a/mercurial/revset.py Mon Oct 10 22:30:09 2016 +0200
+++ b/mercurial/revset.py Fri Oct 14 23:33:00 2016 +0900
@@ -1621,7 +1621,7 @@
ps.add(cl.parentrevs(r)[0])
elif n == 2:
parents = cl.parentrevs(r)
- if len(parents) > 1:
+ if parents[1] != node.nullrev:
ps.add(parents[1])
return subset & ps