--- a/hgext/evolve.py	Sat Mar 12 13:15:28 2016 +0800
+++ b/hgext/evolve.py	Thu Mar 17 17:03:51 2016 -0700
@@ -1998,7 +1998,14 @@
         hg.update(repo, divergent.rev())
     repo.ui.note(_('merging divergent changeset\n'))
     if progresscb: progresscb()
-    if 'partial' in merge.update.__doc__:
+    try:
+        stats = merge.update(repo,
+                             other.node(),
+                             branchmerge=True,
+                             force=False,
+                             ancestor=base.node(),
+                             mergeancestor=True)
+    except TypeError:
         # Mercurial  < 43c00ca887d1 (3.7)
         stats = merge.update(repo,
                              other.node(),
@@ -2007,13 +2014,6 @@
                              partial=None,
                              ancestor=base.node(),
                              mergeancestor=True)
-    else:
-        stats = merge.update(repo,
-                             other.node(),
-                             branchmerge=True,
-                             force=False,
-                             ancestor=base.node(),
-                             mergeancestor=True)
 
     hg._showstats(repo, stats)
     if stats[3]: