diff -r cac9b3591753 -r 372f507f6676 mercurial/revset.py
--- a/mercurial/revset.py	Tue Sep 30 23:09:59 2014 -0500
+++ b/mercurial/revset.py	Wed Oct 01 15:50:40 2014 -0500
@@ -2813,8 +2813,6 @@
         return False
 
     def __and__(self, x):
-        if isinstance(x, baseset):
-            x = x.set()
         return orderedlazyset(self, x.__contains__,
                               ascending=self.isascending())