798     def iterate():

   798     def iterate():

   799         it = iter(revs)

   799         it = iter(revs)

   800         stopiteration = False

   800         stopiteration = False

   801         for windowsize in increasingwindows():

   801         for windowsize in increasingwindows():

   802             nrevs = []

   802             nrevs = []

   804                 rev = next(it, None)

   804                 rev = next(it, None)

   805                 if rev is None:

   805                 if rev is None:

   806                     stopiteration = True

   806                     stopiteration = True

   807                     break

   807                     break

   808                 nrevs.append(rev)

   808                 nrevs.append(rev)