diff -r ba42eb722bb3 -r a740fa28d718 mercurial/commands.py
--- a/mercurial/commands.py	Tue Mar 27 16:17:46 2012 -0500
+++ b/mercurial/commands.py	Wed Mar 28 11:42:17 2012 +0200
@@ -4779,7 +4779,6 @@
                          hint=_('use "hg update" or see "hg help revert"'))
 
     ctx = scmutil.revsingle(repo, opts.get('rev'))
-    node = ctx.node()
 
     if not pats and not opts.get('all'):
         msg = _("no files or directories specified")
@@ -4788,6 +4787,7 @@
                      " or 'hg update -C .' to abort the merge")
             raise util.Abort(msg, hint=hint)
         dirty = util.any(repo.status())
+        node = ctx.node()
         if node != parent:
             if dirty:
                 hint = _("uncommitted changes, use --all to discard all"
@@ -4801,178 +4801,7 @@
             hint = _("use --all to revert all files")
         raise util.Abort(msg, hint=hint)
 
-    mf = ctx.manifest()
-    if node == parent:
-        pmf = mf
-    else:
-        pmf = None
-
-    # need all matching names in dirstate and manifest of target rev,
-    # so have to walk both. do not print errors if files exist in one
-    # but not other.
-
-    names = {}
-
-    wlock = repo.wlock()
-    try:
-        # walk dirstate.
-
-        m = scmutil.match(repo[None], pats, opts)
-        m.bad = lambda x, y: False
-        for abs in repo.walk(m):
-            names[abs] = m.rel(abs), m.exact(abs)
-
-        # walk target manifest.
-
-        def badfn(path, msg):
-            if path in names:
-                return
-            if path in repo[node].substate:
-                ui.warn("%s: %s\n" % (m.rel(path),
-                    'reverting subrepos is unsupported'))
-                return
-            path_ = path + '/'
-            for f in names:
-                if f.startswith(path_):
-                    return
-            ui.warn("%s: %s\n" % (m.rel(path), msg))
-
-        m = scmutil.match(repo[node], pats, opts)
-        m.bad = badfn
-        for abs in repo[node].walk(m):
-            if abs not in names:
-                names[abs] = m.rel(abs), m.exact(abs)
-
-        m = scmutil.matchfiles(repo, names)
-        changes = repo.status(match=m)[:4]
-        modified, added, removed, deleted = map(set, changes)
-
-        # if f is a rename, also revert the source
-        cwd = repo.getcwd()
-        for f in added:
-            src = repo.dirstate.copied(f)
-            if src and src not in names and repo.dirstate[src] == 'r':
-                removed.add(src)
-                names[src] = (repo.pathto(src, cwd), True)
-
-        def removeforget(abs):
-            if repo.dirstate[abs] == 'a':
-                return _('forgetting %s\n')
-            return _('removing %s\n')
-
-        revert = ([], _('reverting %s\n'))
-        add = ([], _('adding %s\n'))
-        remove = ([], removeforget)
-        undelete = ([], _('undeleting %s\n'))
-
-        disptable = (
-            # dispatch table:
-            #   file state
-            #   action if in target manifest
-            #   action if not in target manifest
-            #   make backup if in target manifest
-            #   make backup if not in target manifest
-            (modified, revert, remove, True, True),
-            (added, revert, remove, True, False),
-            (removed, undelete, None, False, False),
-            (deleted, revert, remove, False, False),
-            )
-
-        for abs, (rel, exact) in sorted(names.items()):
-            mfentry = mf.get(abs)
-            target = repo.wjoin(abs)
-            def handle(xlist, dobackup):
-                xlist[0].append(abs)
-                if (dobackup and not opts.get('no_backup') and
-                    os.path.lexists(target)):
-                    bakname = "%s.orig" % rel
-                    ui.note(_('saving current version of %s as %s\n') %
-                            (rel, bakname))
-                    if not opts.get('dry_run'):
-                        util.rename(target, bakname)
-                if ui.verbose or not exact:
-                    msg = xlist[1]
-                    if not isinstance(msg, basestring):
-                        msg = msg(abs)
-                    ui.status(msg % rel)
-            for table, hitlist, misslist, backuphit, backupmiss in disptable:
-                if abs not in table:
-                    continue
-                # file has changed in dirstate
-                if mfentry:
-                    handle(hitlist, backuphit)
-                elif misslist is not None:
-                    handle(misslist, backupmiss)
-                break
-            else:
-                if abs not in repo.dirstate:
-                    if mfentry:
-                        handle(add, True)
-                    elif exact:
-                        ui.warn(_('file not managed: %s\n') % rel)
-                    continue
-                # file has not changed in dirstate
-                if node == parent:
-                    if exact:
-                        ui.warn(_('no changes needed to %s\n') % rel)
-                    continue
-                if pmf is None:
-                    # only need parent manifest in this unlikely case,
-                    # so do not read by default
-                    pmf = repo[parent].manifest()
-                if abs in pmf and mfentry:
-                    # if version of file is same in parent and target
-                    # manifests, do nothing
-                    if (pmf[abs] != mfentry or
-                        pmf.flags(abs) != mf.flags(abs)):
-                        handle(revert, False)
-                else:
-                    handle(remove, False)
-
-        if not opts.get('dry_run'):
-            def checkout(f):
-                fc = ctx[f]
-                repo.wwrite(f, fc.data(), fc.flags())
-
-            audit_path = scmutil.pathauditor(repo.root)
-            for f in remove[0]:
-                if repo.dirstate[f] == 'a':
-                    repo.dirstate.drop(f)
-                    continue
-                audit_path(f)
-                try:
-                    util.unlinkpath(repo.wjoin(f))
-                except OSError:
-                    pass
-                repo.dirstate.remove(f)
-
-            normal = None
-            if node == parent:
-                # We're reverting to our parent. If possible, we'd like status
-                # to report the file as clean. We have to use normallookup for
-                # merges to avoid losing information about merged/dirty files.
-                if p2 != nullid:
-                    normal = repo.dirstate.normallookup
-                else:
-                    normal = repo.dirstate.normal
-            for f in revert[0]:
-                checkout(f)
-                if normal:
-                    normal(f)
-
-            for f in add[0]:
-                checkout(f)
-                repo.dirstate.add(f)
-
-            normal = repo.dirstate.normallookup
-            if node == parent and p2 == nullid:
-                normal = repo.dirstate.normal
-            for f in undelete[0]:
-                checkout(f)
-                normal(f)
-
-    finally:
-        wlock.release()
+    return cmdutil.revert(ui, repo, ctx, (parent, p2), *pats, **opts)
 
 @command('rollback', dryrunopts +
          [('f', 'force', False, _('ignore safety measures'))])