Improved default tag for durations (#464)

marshal.go

@@ -830,7 +830,21 @@ func (d *Decoder) valueFromTree(mtype reflect.Type, tval *Tree, mval1 *reflect.V
 					case reflect.Int32:
 						val, err = strconv.ParseInt(opts.defaultValue, 10, 32)
 					case reflect.Int64:
+						// Check if the provided number has a non-numeric extension.
+						var hasExtension bool
+						if len(opts.defaultValue) > 0 {
+							lastChar := opts.defaultValue[len(opts.defaultValue)-1]
+							if lastChar < '0' || lastChar > '9' {
+								hasExtension = true
+							}
+						}
+						// If the value is a time.Duration with extension, parse as duration.
+						// If the value is an int64 or a time.Duration without extension, parse as number.
+						if hasExtension && mvalf.Type().String() == "time.Duration" {
+							val, err = time.ParseDuration(opts.defaultValue)
+						} else {
 							val, err = strconv.ParseInt(opts.defaultValue, 10, 64)
+						}
 					case reflect.Float32:
 						val, err = strconv.ParseFloat(opts.defaultValue, 32)
 					case reflect.Float64:

marshal_test.go

@@ -2300,6 +2300,8 @@ func TestUnmarshalDefault(t *testing.T) {
 		Int64Field        int64         `default:"-64"`
 		Float32Field      float32       `default:"32.1"`
 		Float64Field      float64       `default:"64.1"`
+		DurationField     time.Duration `default:"120ms"`
+		DurationField2    time.Duration `default:"120000000"`
 		NonEmbeddedStruct struct {
 			StringField string `default:"b"`
 		}
@@ -2353,6 +2355,12 @@ func TestUnmarshalDefault(t *testing.T) {
 	if doc.Float64Field != 64.1 {
 		t.Errorf("Float64Field should be 64.1, not %f", doc.Float64Field)
 	}
+	if doc.DurationField != 120*time.Millisecond {
+		t.Errorf("DurationField should be 120ms, not %s", doc.DurationField.String())
+	}
+	if doc.DurationField2 != 120*time.Millisecond {
+		t.Errorf("DurationField2 should be 120000000, not %d", doc.DurationField2)
+	}
 	if doc.NonEmbeddedStruct.StringField != "b" {
 		t.Errorf("StringField should be \"b\", not %s", doc.NonEmbeddedStruct.StringField)
 	}
@@ -2408,6 +2416,17 @@ func TestUnmarshalDefaultFailureFloat64(t *testing.T) {
 	}
 }
 
+func TestUnmarshalDefaultFailureDuration(t *testing.T) {
+	var doc struct {
+		Field time.Duration `default:"blah"`
+	}
+
+	err := Unmarshal([]byte(``), &doc)
+	if err == nil {
+		t.Fatal("should error")
+	}
+}
+
 func TestUnmarshalDefaultFailureUnsupported(t *testing.T) {
 	var doc struct {
 		Field struct{} `default:"blah"`