--- a/mercurial/templatekw.py	Sat Jun 17 13:18:03 2017 +0900
+++ b/mercurial/templatekw.py	Sat Jun 17 13:23:55 2017 +0900
@@ -568,8 +568,9 @@
     predecessors = sorted(obsutil.closestpredecessors(repo, ctx.node()))
     predecessors = map(hex, predecessors)
 
-    return _hybrid(None, predecessors, lambda x: {'node': x},
-                   lambda d: d['node'][:12])
+    return _hybrid(None, predecessors,
+                   lambda x: {'ctx': repo[x], 'revcache': {}},
+                   lambda d: short(scmutil.binnode(d['ctx'])))
 
 @templatekeyword('p1rev')
 def showp1rev(repo, ctx, templ, **args):