435     dirstatebackupname = b'dirstate.shelve'

   435     # disable the transaction invalidation of the dirstate, to preserve the

   436     repo.dirstate.savebackup(None, dirstatebackupname)

   436     # current change in memory.

   437     tr.abort()

   437     ds = repo.dirstate

   438     repo.dirstate.restorebackup(None, dirstatebackupname)

   438     # The assert below check that nobody else did such wrapping.

   439     #

   440     # These is not such other wrapping currently, but if someone try to

   441     # implement one in the future, this will explicitly break here instead of

   442     # misbehaving in subtle ways.

   443     assert 'invalidate' not in vars(ds)

   444     try:

   445         # note : we could simply disable the transaction abort callback, but

   446         # other code also tries to rollback and invalidate this.

   447         ds.invalidate = lambda: None

   448         tr.abort()

   449     finally:

   450         del ds.invalidate

   451     # manually write the change in memory since we can no longer rely on the

   452     # transaction to do so.

   453     assert repo.currenttransaction() is None

   454     repo.dirstate.write(None)