func addrNumber()

in internal/codewalk/codewalk.go [391:468]

• 72 lines of code
• 29 McCabe index (conditional complexity)

func addrNumber(data []byte, lo, hi int, dir byte, n int, charOffset bool) (int, int, error) {
	switch dir {
	case 0:
		lo = 0
		hi = 0
		fallthrough

	case '+':
		if charOffset {
			pos := hi
			for ; n > 0 && pos < len(data); n-- {
				_, size := utf8.DecodeRune(data[pos:])
				pos += size
			}
			if n == 0 {
				return pos, pos, nil
			}
			break
		}
		// find next beginning of line
		if hi > 0 {
			for hi < len(data) && data[hi-1] != '\n' {
				hi++
			}
		}
		lo = hi
		if n == 0 {
			return lo, hi, nil
		}
		for ; hi < len(data); hi++ {
			if data[hi] != '\n' {
				continue
			}
			switch n--; n {
			case 1:
				lo = hi + 1
			case 0:
				return lo, hi + 1, nil
			}
		}

	case '-':
		if charOffset {
			// Scan backward for bytes that are not UTF-8 continuation bytes.
			pos := lo
			for ; pos > 0 && n > 0; pos-- {
				if data[pos]&0xc0 != 0x80 {
					n--
				}
			}
			if n == 0 {
				return pos, pos, nil
			}
			break
		}
		// find earlier beginning of line
		for lo > 0 && data[lo-1] != '\n' {
			lo--
		}
		hi = lo
		if n == 0 {
			return lo, hi, nil
		}
		for ; lo >= 0; lo-- {
			if lo > 0 && data[lo-1] != '\n' {
				continue
			}
			switch n--; n {
			case 1:
				hi = lo
			case 0:
				return lo, hi, nil
			}
		}
	}

	return 0, 0, errors.New("address out of range")
}