func GetUsage()

in common/util.go [369:424]
43 lines of code
12 McCabe index (conditional complexity)

func GetUsage(path string) (float64, error) {
	var currSize float64
	var out bytes.Buffer

	if selectedDuPath == "" {
		selectedDuPath = "-"
		for _, dup := range duPath {
			_, err := os.Stat(dup)
			if err == nil {
				selectedDuPath = dup
				break
			}
		}
	}

	if selectedDuPath == "-" {
		return 0, fmt.Errorf("failed to find du")
	}

	// du - estimates file space usage
	// https://man7.org/linux/man-pages/man1/du.1.html
	// Note: We cannot just pass -BM as a parameter here since it will result in less accurate estimates of the size of the path
	// (i.e. du will round up to 1M if the path is smaller than 1M).
	cmd := exec.Command(selectedDuPath, "-sh", path)
	cmd.Stdout = &out

	err := cmd.Run()
	if err != nil {
		return 0, err
	}

	size := strings.Split(out.String(), "\t")[0]
	if size == "0" {
		return 0, nil
	}

	// some OS's use "," instead of "." that will not work for float parsing - replace it
	size = strings.Replace(size, ",", ".", 1)
	parsed, err := strconv.ParseFloat(size[:len(size)-1], 64)
	if err != nil {
		return 0, fmt.Errorf("failed to parse du output")
	}

	switch size[len(size)-1] {
	case 'K':
		currSize = parsed / float64(1024)
	case 'M':
		currSize = parsed
	case 'G':
		currSize = parsed * 1024
	case 'T':
		currSize = parsed * 1024 * 1024
	}

	return currSize, nil
}