Golang line reading that indents.

indent-lines.go

func IndentLines(indent, code string) string {
	reader := bufio.NewReader(bytes.NewBufferString(code))
	buf := bytes.NewBufferString("")
	line, prefix, err := reader.ReadLine()

	for err == nil && line != nil {
		if !prefix {
			buf.WriteString(indent)
		}
		s := strings.Trim(string(line), " \t\r\n")
		buf.WriteString(s)
		if !prefix {
			buf.WriteString("\n")
		}
		line, prefix, err = reader.ReadLine()
	}

	return buf.String()
}