transaction: reorder unlinking .hg/journal and .hg/journal.backupfiles After this reordering, absence of '.hg/journal' just before starting new transaction means also absence of '.hg/journal.backupfiles'. In this case, all temporary files for preceding transaction should be completely unlinked, and HG_PENDING doesn't cause unintentional reading stalled temporary files in. Otherwise, 'repo.transaction()' raises exception with "run 'hg recover' to clean up transaction" hint.