[PATCH 3 of 5] transplant: use set for prune lookup

[Mads Kiilerich]

# HG changeset patch
# User Mads Kiilerich <madski at unity3d.com>
# Date 1366133519 -7200
#      Tue Apr 16 19:31:59 2013 +0200
# Node ID 3f621c427c998d049888ab60e6f40b7258f9f65f
# Parent  7b1520771113094fdbe19511ef7ef22f2d2666f2
transplant: use set for prune lookup

diff --git a/hgext/transplant.py b/hgext/transplant.py
--- a/hgext/transplant.py
+++ b/hgext/transplant.py
@@ -633,8 +633,8 @@
 
         tf = tp.transplantfilter(repo, source, p1)
         if opts.get('prune'):
-            prune = [source.lookup(r)
-                     for r in scmutil.revrange(source, opts.get('prune'))]
+            prune = set(source.lookup(r)
+                        for r in scmutil.revrange(source, opts.get('prune')))
             matchfn = lambda x: tf(x) and x not in prune
         else:
             matchfn = tf