feat: add feature for humanize byte unit

formatter/byte.go

@@ -0,0 +1,178 @@
+package formatter
+
+import (
+	"fmt"
+	"math"
+	"strconv"
+	"strings"
+	"unicode"
+)
+
+//
+// code logic come from:
+// https://github.com/docker/go-units/blob/master/size.go
+
+// http://en.wikipedia.org/wiki/Binary_prefix
+const (
+	// Decimal
+	UnitB  = 1
+	UnitKB = 1000
+	UnitMB = 1000 * UnitKB
+	UnitGB = 1000 * UnitMB
+	UnitTB = 1000 * UnitGB
+	UnitPB = 1000 * UnitTB
+	UnitEB = 1000 * UnitPB
+
+	// Binary
+	UnitBiB = 1
+	UnitKiB = 1024
+	UnitMiB = 1024 * UnitKiB
+	UnitGiB = 1024 * UnitMiB
+	UnitTiB = 1024 * UnitGiB
+	UnitPiB = 1024 * UnitTiB
+	UnitEiB = 1024 * UnitPiB
+)
+
+// type byteUnitMap map[byte]int64
+
+var (
+	decimalByteMap = map[string]uint64{
+		"b":  UnitB,
+		"kb": UnitKB,
+		"mb": UnitMB,
+		"gb": UnitGB,
+		"tb": UnitTB,
+		"pb": UnitPB,
+		"eb": UnitEB,
+
+		// Without suffix
+		"":  UnitB,
+		"k": UnitKB,
+		"m": UnitMB,
+		"g": UnitGB,
+		"t": UnitTB,
+		"p": UnitPB,
+		"e": UnitEB,
+	}
+
+	binaryByteMap = map[string]uint64{
+		"bi":  UnitBiB,
+		"kib": UnitKiB,
+		"mib": UnitMiB,
+		"gib": UnitGiB,
+		"tib": UnitTiB,
+		"pib": UnitPiB,
+		"eib": UnitEiB,
+
+		// Without suffix
+		"":   UnitBiB,
+		"ki": UnitKiB,
+		"mi": UnitMiB,
+		"gi": UnitGiB,
+		"ti": UnitTiB,
+		"pi": UnitPiB,
+		"ei": UnitEiB,
+	}
+)
+
+var (
+	decimalByteUnits = []string{"B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"}
+	binaryByteUnits  = []string{"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"}
+)
+
+// DecimalBytes returns a human readable byte size under decimal standard (base 1000)
+// The precision parameter specifies the number of digits after the decimal point, which defaults to 4.
+// Play: todo
+func DecimalBytes(size float64, precision ...int) string {
+	p := 5
+	if len(precision) > 0 {
+		p = precision[0] + 1
+	}
+	size, unit := calculateByteSize(size, 1000.0, decimalByteUnits)
+
+	return fmt.Sprintf("%.*g%s", p, size, unit)
+}
+
+// BinaryBytes returns a human-readable byte size under decimal standard (base 1024)
+// The precision parameter specifies the number of digits after the decimal point, which defaults to 4.
+// Play: todo
+func BinaryBytes(size float64, precision ...int) string {
+	p := 5
+	if len(precision) > 0 {
+		p = precision[0] + 1
+	}
+	size, unit := calculateByteSize(size, 1024.0, binaryByteUnits)
+
+	return fmt.Sprintf("%.*g%s", p, size, unit)
+}
+
+func calculateByteSize(size float64, base float64, byteUnits []string) (float64, string) {
+	i := 0
+	unitsLimit := len(byteUnits) - 1
+	for size >= base && i < unitsLimit {
+		size = size / base
+		i++
+	}
+	return size, byteUnits[i]
+}
+
+// ParseDecimalBytes the human readable bytes size string into the amount it represents(base 1000).
+// ParseDecimalBytes("42 MB") -> 42000000, nil
+// Play: todo
+func ParseDecimalBytes(size string) (uint64, error) {
+	return parseBytes(size, "decimal")
+}
+
+// ParseBinaryBytes the human readable bytes size string into the amount it represents(base 1024).
+// ParseBinaryBytes("42 mib") -> 44040192, nil
+// Play: todo
+func ParseBinaryBytes(size string) (uint64, error) {
+	return parseBytes(size, "binary")
+}
+
+// see https://github.com/dustin/go-humanize/blob/master/bytes.go
+func parseBytes(s string, kind string) (uint64, error) {
+	lastDigit := 0
+	hasComma := false
+	for _, r := range s {
+		if !(unicode.IsDigit(r) || r == '.' || r == ',') {
+			break
+		}
+		if r == ',' {
+			hasComma = true
+		}
+		lastDigit++
+	}
+
+	num := s[:lastDigit]
+	if hasComma {
+		num = strings.Replace(num, ",", "", -1)
+	}
+
+	f, err := strconv.ParseFloat(num, 64)
+	if err != nil {
+		return 0, err
+	}
+
+	extra := strings.ToLower(strings.TrimSpace(s[lastDigit:]))
+
+	if kind == "decimal" {
+		if m, ok := decimalByteMap[extra]; ok {
+			f *= float64(m)
+			if f >= math.MaxUint64 {
+				return 0, fmt.Errorf("too large: %v", s)
+			}
+			return uint64(f), nil
+		}
+	} else {
+		if m, ok := binaryByteMap[extra]; ok {
+			f *= float64(m)
+			if f >= math.MaxUint64 {
+				return 0, fmt.Errorf("too large: %v", s)
+			}
+			return uint64(f), nil
+		}
+	}
+
+	return 0, fmt.Errorf("unhandled size name: %v", extra)
+}

formatter/byte_test.go

@@ -0,0 +1,87 @@
+package formatter
+
+import (
+	"testing"
+
+	"github.com/duke-git/lancet/v2/internal"
+)
+
+func TestDecimalBytes(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDecimalBytes")
+
+	assert.Equal("1KB", DecimalBytes(1000))
+	assert.Equal("1.024KB", DecimalBytes(1024))
+	assert.Equal("1.2346MB", DecimalBytes(1234567))
+	assert.Equal("1.235MB", DecimalBytes(1234567, 3))
+	assert.Equal("1.123GB", DecimalBytes(float64(1.123*UnitGB)))
+	assert.Equal("2.123TB", DecimalBytes(float64(2.123*UnitTB)))
+	assert.Equal("3.123PB", DecimalBytes(float64(3.123*UnitPB)))
+	assert.Equal("4.123EB", DecimalBytes(float64(4.123*UnitEB)))
+	assert.Equal("1EB", DecimalBytes(float64(1000*UnitPB)))
+}
+
+func TestBinaryBytes(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBinaryBytes")
+
+	assert.Equal("1KiB", BinaryBytes(1024))
+	assert.Equal("1MiB", BinaryBytes(1024*1024))
+	assert.Equal("1.1774MiB", BinaryBytes(1234567))
+	assert.Equal("1.18MiB", BinaryBytes(1234567, 2))
+}
+
+func TestParseDecimalBytes(t *testing.T) {
+	assert := internal.NewAssert(t, "TestParseDecimalBytes")
+
+	cases := map[string]uint64{
+		"12":      uint64(12),
+		"12 k":    uint64(12000),
+		"12 kb":   uint64(12000),
+		"12kb":    uint64(12000),
+		"12k":     uint64(12000),
+		"12K":     uint64(12000),
+		"12KB":    uint64(12000),
+		"12 K":    uint64(12000),
+		"12 KB":   uint64(12000),
+		"12 Kb":   uint64(12000),
+		"12 kB":   uint64(12000),
+		"12.2 KB": uint64(12200),
+	}
+
+	for k, v := range cases {
+		result, err := ParseDecimalBytes(k)
+		assert.Equal(v, result)
+		assert.IsNil(err)
+	}
+
+	_, err := ParseDecimalBytes("12 AB")
+	assert.IsNotNil(err)
+}
+
+func TestParseBinaryBytes(t *testing.T) {
+	assert := internal.NewAssert(t, "TestParseBinaryBytes")
+
+	cases := map[string]uint64{
+		"12":       uint64(12),
+		"12 ki":    uint64(12288),
+		"12 kib":   uint64(12288),
+		"12kib":    uint64(12288),
+		"12ki":     uint64(12288),
+		"12KI":     uint64(12288),
+		"12KIB":    uint64(12288),
+		"12KiB":    uint64(12288),
+		"12 Ki":    uint64(12288),
+		"12 KiB":   uint64(12288),
+		"12 Kib":   uint64(12288),
+		"12 kiB":   uint64(12288),
+		"12.2 KiB": uint64(12492),
+	}
+
+	for k, v := range cases {
+		result, err := ParseBinaryBytes(k)
+		assert.Equal(v, result)
+		assert.IsNil(err)
+	}
+
+	_, err := ParseDecimalBytes("12 AB")
+	assert.IsNotNil(err)
+}