fix/time-duration

defaults.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"reflect"
 	"strconv"
+	"strings"
 	"time"
 )
 
@@ -65,6 +66,9 @@ func setField(field reflect.Value, defaultVal string) error {
 		if unmarshalByInterface(field, defaultVal) {
 			return nil
 		}
+		if parseByMethod(field, defaultVal) {
+			return nil
+		}
 
 		switch field.Kind() {
 		case reflect.Bool:
@@ -217,6 +221,20 @@ func unmarshalByInterface(field reflect.Value, defaultVal string) bool {
 	return false
 }
 
+func parseByMethod(field reflect.Value, defaultVal string) bool {
+	if field.Type() == reflect.TypeOf(time.Duration(0)) {
+		if defaultVal != "" {
+			defaultVal = strings.TrimSpace(defaultVal)
+			duration, err := time.ParseDuration(defaultVal)
+			if err == nil {
+				field.Set(reflect.ValueOf(duration))
+				return true
+			}
+		}
+	}
+	return false
+}
+
 func isInitialValue(field reflect.Value) bool {
 	return reflect.DeepEqual(reflect.Zero(field.Type()).Interface(), field.Interface())
 }

defaults_test.go

@@ -312,6 +312,9 @@ func TestInit(t *testing.T) {
 		if sample.String != "hello" {
 			t.Errorf("it should initialize string")
 		}
+		if sample.Duration != 10000000000 {
+			t.Errorf("it should initialize time.Duration")
+		}
 
 		if sample.IntOct != 0o1 {
 			t.Errorf("it should initialize int with octal literal")