# HG changeset patch
# User Matt Mackall <mpm@selenic.com>
# Date 1405378531 18000
# Node ID dd716807fd23d48677efd46bad8c759e3da2511e
# Parent  e353fac7db2633c59d29a5059a08830a498aea49
revset: maintain ordering when subtracting from a baseset (issue4289)

diff -r e353fac7db26 -r dd716807fd23 mercurial/revset.py
--- a/mercurial/revset.py	Tue Jul 15 00:59:09 2014 +0900
+++ b/mercurial/revset.py	Mon Jul 14 17:55:31 2014 -0500
@@ -2243,11 +2243,7 @@
         """Returns a new object with the substraction of the two collections.
 
         This is part of the mandatory API for smartset."""
-        if isinstance(other, baseset):
-            s = other.set()
-        else:
-            s = set(other)
-        return baseset(self.set() - s)
+        return self.filter(lambda x: x not in other)
 
     def __and__(self, other):
         """Returns a new object with the intersection of the two collections.
diff -r e353fac7db26 -r dd716807fd23 tests/test-revset.t
--- a/tests/test-revset.t	Tue Jul 15 00:59:09 2014 +0900
+++ b/tests/test-revset.t	Mon Jul 14 17:55:31 2014 -0500
@@ -1008,6 +1008,11 @@
   $ log 'min(1 or 2) and not 1'
   $ log 'last(1 or 2, 1) and not 2'
 
+issue4289 - ordering of built-ins
+  $ hg log -M -q -r 3:2
+  3:8528aa5637f2
+  2:5ed5505e9f1c
+
 test revsets started with 40-chars hash (issue3669)
 
   $ ISSUE3669_TIP=`hg tip --template '{node}'`