covered += int64(b.NumStmt)
		}
	}
	if total == 0 {
		return 0
	}
	return float64(covered) / float64(total) * 100
}

// htmlGen generates an HTML coverage report with the provided filename,
// source code, and tokens, and writes it to the given Writer.
func htmlGen(w io.Writer, src []byte, boundaries []cover.Boundary) error {
	dst := bufio.NewWriter(w)
	for i := range src {