diff -r 70a2082f855a -r 48919d246a47 mercurial/revset.py
--- a/mercurial/revset.py	Sat Jun 27 17:05:28 2015 +0900
+++ b/mercurial/revset.py	Sat Jun 27 17:25:01 2015 +0900
@@ -282,6 +282,10 @@
         raise error.ParseError(err)
     return l
 
+def getkwargs(x, funcname, keys):
+    return parser.buildargsdict(getlist(x), funcname, keys.split(),
+                                keyvaluenode='keyvalue', keynode='symbol')
+
 def isvalidsymbol(tree):
     """Examine whether specified ``tree`` is valid ``symbol`` or not
     """