596         if isinstance(key, int):

   596         return self[key].node()

   597             return self.changelog.node(key)

   598         elif key == '.':

   599             return self.dirstate.p1()

   600         elif key == 'null':

   601             return nullid

   602         elif key == 'tip':

   603             return self.changelog.tip()

   604         n = self.changelog._match(key)

   605         if n:

   606             return n

   607         if key in self._bookmarks:

   608             return self._bookmarks[key]

   609         if key in self.tags():

   610             return self.tags()[key]

   611         if key in self.branchtags():

   612             return self.branchtags()[key]

   613         n = self.changelog._partialmatch(key)

   614         if n:

   615             return n

   616 

   617         # can't find key, check if it might have come from damaged dirstate

   618         if key in self.dirstate.parents():

   619             raise error.Abort(_("working directory has unknown parent '%s'!")

   620                               % short(key))

   621         try:

   622             if len(key) == 20:

   623                 key = hex(key)

   624         except TypeError:

   625             pass

   626         raise error.RepoLookupError(_("unknown revision '%s'") % key)