Add ValidateValuer

validate.go

@@ -223,27 +223,28 @@ func getTagFuncs(i int, ft reflect.StructField, kind reflect.Kind, tags []string
 			ptr = false
 		}
 
+		var f validateCheck
+
 		if tag == `optional` {
-			rules = append(rules, rule{i, func(rv reflect.Value) ([]ValidationError, bool) {
+			f = func(rv reflect.Value) ([]ValidationError, bool) {
 				check, _ := getTagFunc(`required`, ``, kind)
 				return nil, check(rv, nil)
-			}})
-			continue
-		}
-
-		var not bool
-		if strings.HasPrefix(tag, `!`) {
-			not = true
-		}
-
-		check, val := getTagFunc(strings.TrimPrefix(tag, `!`), value, kind)
-
-		f := func(rv reflect.Value) ([]ValidationError, bool) {
-			if check(rv, val) == !not {
-				return nil, true
+			}
+		} else {
+			var not bool
+			if strings.HasPrefix(tag, `!`) {
+				not = true
 			}
 
-			return []ValidationError{{Field: []Field{{nil, &ft}}, Check: tag, Value: value}}, false
+			check, val := getTagFunc(strings.TrimPrefix(tag, `!`), value, kind)
+
+			f = func(rv reflect.Value) ([]ValidationError, bool) {
+				if check(rv, val) == !not {
+					return nil, true
+				}
+
+				return []ValidationError{{Field: []Field{{nil, &ft}}, Check: tag, Value: value}}, false
+			}
 		}
 
 		if ptr {

validate_test.go

@@ -135,14 +135,19 @@ func (v val) ValidateValue() interface{} {
 func TestValidateValuer(t *testing.T) {
 	type s struct {
 		A val `validate:"required,lt=2"`
+		B val `validate:"optional,eq=3"`
 	}
 
-	pass := s{val{Valid: true}}
+	pass1 := s{val{Valid: true}, val{}}
+	pass2 := s{val{Valid: true}, val{Int: 3, Valid: true}}
 
 	fail1 := s{}
-	fail2 := s{val{Int: 2, Valid: true}}
+	fail2 := s{val{Int: 2, Valid: true}, val{}}
+	fail3 := s{val{Valid: true}, val{Int: 2, Valid: true}}
 
-	check(t, pass, 0)
+	check(t, pass1, 0)
+	check(t, pass2, 0)
 	check(t, fail1, 1)
 	check(t, fail2, 1)
+	check(t, fail3, 1)
 }