--- a/mercurial/revsetlang.py	Thu Oct 11 03:13:53 2018 +0200
+++ b/mercurial/revsetlang.py	Thu Oct 11 03:15:04 2018 +0200
@@ -355,9 +355,6 @@
     elif op == 'keyvalue':
         return (op, x[1], _analyze(x[2]))
     elif op == 'func':
-        f = getsymbol(x[1])
-        if f == 'revset':
-            return _analyze(x[2])
         return (op, x[1], _analyze(x[2]))
     raise ValueError('invalid operator %r' % op)