# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 1412987409 25200
# Node ID 1ddefcfcd3e6da10e44d3de094c9e4265c5c9deb
# Parent  0f44d35731d69937c98ad9e1368cb6bd2ca6d029
revsets: use '&' instead of '.filter' in head

More high level operations are more likely to be optimised.

diff -r 0f44d35731d6 -r 1ddefcfcd3e6 mercurial/revset.py
--- a/mercurial/revset.py	Sat Jun 20 11:07:36 2015 -0400
+++ b/mercurial/revset.py	Fri Oct 10 17:30:09 2014 -0700
@@ -1113,10 +1113,9 @@
         hs.update(cl.rev(h) for h in ls)
     # XXX using a set to feed the baseset is wrong. Sets are not ordered.
     # This does not break because of other fullreposet misbehavior.
-    # XXX We should not be using '.filter' here, but combines subset with '&'
     # XXX We should combine with subset first: 'subset & baseset(...)'. This is
     # necessary to ensure we preserve the order in subset.
-    return baseset(hs).filter(subset.__contains__)
+    return baseset(hs) & subset
 
 def heads(repo, subset, x):
     """``heads(set)``