[PATCH 5 of 6] revset: unify code flow in `bookmark`

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at fb.com>
# Date 1410976705 25200
#      Wed Sep 17 10:58:25 2014 -0700
# Node ID ac8639727377910aacfcd326bd3dec008a577b82
# Parent  542a93adfe2a1044d2f0b300c32e72670216001d
revset: unify code flow in `bookmark`

We refactor the code of the bookmark revset to have a single return. This will
allow us to sanitize the content of the set.

diff --git a/mercurial/revset.py b/mercurial/revset.py
--- a/mercurial/revset.py
+++ b/mercurial/revset.py
@@ -446,31 +446,29 @@ def bookmark(repo, subset, x):
     if args:
         bm = getstring(args[0],
                        # i18n: "bookmark" is a keyword
                        _('the argument to bookmark must be a string'))
         kind, pattern, matcher = _stringmatcher(bm)
+        bms = set()
         if kind == 'literal':
             bmrev = repo._bookmarks.get(pattern, None)
             if not bmrev:
                 raise util.Abort(_("bookmark '%s' does not exist") % bm)
-            bmrev = repo[bmrev].rev()
-            return subset.filter(lambda r: r == bmrev)
+            bms.add(repo[bmrev].rev())
         else:
             matchrevs = set()
             for name, bmrev in repo._bookmarks.iteritems():
                 if matcher(name):
                     matchrevs.add(bmrev)
             if not matchrevs:
                 raise util.Abort(_("no bookmarks exist that match '%s'")
                                  % pattern)
-            bmrevs = set()
             for bmrev in matchrevs:
-                bmrevs.add(repo[bmrev].rev())
-            return subset & bmrevs
-
-    bms = set([repo[r].rev()
-               for r in repo._bookmarks.values()])
+                bms.add(repo[bmrev].rev())
+    else:
+        bms = set([repo[r].rev()
+                   for r in repo._bookmarks.values()])
     return subset.filter(bms.__contains__)
 
 def branch(repo, subset, x):
     """``branch(string or set)``
     All changesets belonging to the given branch or the branches of the given