code: func (t *Torrent) PieceStateRuns() []PieceStateRun {
  	t.cl.rLock()
  	defer t.cl.rUnlock()
  	return t.pieceStateRuns()
  }
docs: // Returns the state of pieces of the torrent. They are grouped into runs of
  // same state. The sum of the state run lengths is the number of pieces
  // in the torrent.