# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 1410976756 25200
# Node ID 44f471102f3a357b2e7fda4f91c571b29bc50b42
# Parent  6261b9c549a24a84c00c608d7732fa1d9ea676de
revset: use `subset &` in `follow`

This takes advantage of the `fullreposet` smartness.


revset #0: follow(COPYING)
0) wall 0.002446 comb 0.000000 user 0.000000 sys 0.000000 (best of 735)
1) wall 0.000331 comb 0.000000 user 0.000000 sys 0.000000 (best of 5672)

diff -r 6261b9c549a2 -r 44f471102f3a mercurial/revset.py
--- a/mercurial/revset.py	Wed Sep 17 10:58:50 2014 -0700
+++ b/mercurial/revset.py	Wed Sep 17 10:59:16 2014 -0700
@@ -834,7 +834,7 @@
     else:
         s = _revancestors(repo, baseset([c.rev()]), followfirst)
 
-    return subset.filter(s.__contains__)
+    return subset & s
 
 def follow(repo, subset, x):
     """``follow([file])``