code: func (b *blame) maxAuthorLength() int {
  	memo := make(map[plumbing.Hash]struct{}, len(b.graph)-1)
  	fVs := b.graph[len(b.graph)-1]
  	m := 0
  	for ln := range fVs {
  		if _, ok := memo[fVs[ln].Hash]; ok {
  			continue
  		}
  		memo[fVs[ln].Hash] = struct{}{}
  		m = max(m, utf8.RuneCountInString(prettyPrintAuthor(fVs[ln])))
  	}
  	return m
  }
docs: // utility function to calculate the number of runes needed
  // to print the longest author name in the blame of a file.