Merge pull request #12 from moul/dev/moul/short-duration

feat: add ShortDuration

README.md

@@ -67,6 +67,10 @@ func PrettyJSON(input interface{}) string
 
 func Sha1(data []byte) []byte
 func Sha1Hex(data []byte) string
+func ShortDuration(d time.Duration) string
+    ShortDuration returns a short human-friendly representation of a duration.
+    For duration < 100 days, the output length will be <= 7.
+
 func SilentClose(closer io.Closer)
     SilentClose calls an io.Closer.Close() function and ignore potential errors.
 

time.go

@@ -0,0 +1,38 @@
+package u
+
+import (
+	"fmt"
+	"strings"
+	"time"
+)
+
+// ShortDuration returns a short human-friendly representation of a duration.
+// For duration < 100 days, the output length will be <= 7.
+func ShortDuration(d time.Duration) string {
+	var s string
+	switch {
+	case d < time.Microsecond:
+		return d.String()
+	case d < time.Millisecond:
+		return d.Round(time.Microsecond / 10).String()
+	case d < time.Second:
+		return d.Round(time.Millisecond / 10).String()
+	case d < time.Minute:
+		return d.Round(time.Second / 10).String()
+	case d < time.Hour:
+		s = d.Round(time.Second).String()
+	case d < time.Hour*24:
+		s = d.Round(time.Second).String()
+	default:
+		days := float64(d) / float64(time.Hour*24)
+		d %= (time.Hour * 24)
+		s = fmt.Sprintf("%dd%s", int(days), d.Round(time.Minute).String())
+	}
+	if len(s) > 2 {
+		s = strings.TrimSuffix(s, "0s")
+	}
+	if len(s) > 2 {
+		s = strings.TrimSuffix(s, "0m")
+	}
+	return s
+}

time_test.go

@@ -0,0 +1,70 @@
+package u_test
+
+import (
+	"fmt"
+	"time"
+
+	"moul.io/u"
+)
+
+func ExampleShortDuration() {
+	fmt.Println(u.ShortDuration(time.Nanosecond * 0))
+	fmt.Println(u.ShortDuration(time.Nanosecond))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 12))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 123))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 1234))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 12345))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 123456))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 1234567))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 12345678))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 123456789))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 1234567891))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 12345678912))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 123456789123))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 1234567891234))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 12345678912345))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 123456789123456))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 1234567891234567))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 12345678912345678))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 123456789123456789))
+	fmt.Println(u.ShortDuration(time.Nanosecond * 1234567891234567891))
+	fmt.Println("-------")
+	fmt.Println(u.ShortDuration(time.Nanosecond))
+	fmt.Println(u.ShortDuration(time.Microsecond))
+	fmt.Println(u.ShortDuration(time.Millisecond))
+	fmt.Println(u.ShortDuration(time.Second))
+	fmt.Println(u.ShortDuration(time.Minute))
+	fmt.Println(u.ShortDuration(time.Hour))
+	fmt.Println(u.ShortDuration(time.Hour * 24))
+	fmt.Println(u.ShortDuration(time.Hour + time.Second))
+	// Output:
+	// 0s
+	// 1ns
+	// 12ns
+	// 123ns
+	// 1.2µs
+	// 12.3µs
+	// 123.5µs
+	// 1.2ms
+	// 12.3ms
+	// 123.5ms
+	// 1.2s
+	// 12.3s
+	// 2m3s
+	// 20m35s
+	// 3h25m46s
+	// 1d10h18m
+	// 14d6h56m
+	// 142d21h21m
+	// 1428d21h33m
+	// 14288d23h32m
+	// -------
+	// 1ns
+	// 1µs
+	// 1ms
+	// 1s
+	// 1m
+	// 1h
+	// 1d
+	// 1h0m1s
+}