hgext/fetch.py

--- a/hgext/fetch.py	Fri Jan 25 23:43:11 2019 -0800
+++ b/hgext/fetch.py	Fri Jan 25 23:22:23 2019 -0800
@@ -68,7 +68,7 @@
     if date:
         opts['date'] = dateutil.parsedate(date)
 
-    parent, _p2 = repo.dirstate.parents()
+    parent = repo.dirstate.p1()
     branch = repo.dirstate.branch()
     try:
         branchnode = repo.branchtip(branch)