code: func (ix *Index) DisableOutOfOrderIndexing() {
  	ix.Lock()
  	defer ix.Unlock()
  	ix.oooDisabled = true
  }
docs: // DisableOutOfOrderIndexing should only be used for tests. It disables the
  // asynchronous, out of order, indexing to demonstrate that e.g. reindexing fails
  // without it.