code: func newRowKey(project, path string, index, count int64) *rowKey {
  	h := sha256.New()
  
  	_, _ = h.Write([]byte(project))
  	_, _ = h.Write([]byte("/"))
  	_, _ = h.Write([]byte(path))
  	return &rowKey{
  		pathHash: h.Sum(nil),
  		index:    index,
  		count:    count,
  	}
  }
docs: // newRowKey generates the row key matching a given entry path and index.