validation: fix absence detection for nullable fields

Author: System-Glitch

validation/unique.go

@@ -42,7 +42,7 @@ var clickhouseTypes = map[reflect.Type]string{
 // according to the provided database scope. Uniqueness is checked using a COUNT query.
 type UniqueValidator struct {
 	BaseValidator
-	Scope func(db *gorm.DB, val any) *gorm.DB
+	Scope func(db *gorm.DB, val any) *gorm.DB // TODO v6: change val to validation.Context
 }
 
 // Validate checks the field under validation satisfies this validator's criteria.

validation/validator.go

@@ -449,7 +449,7 @@ func (v *validator) isAbsent(field *Field, c *walk.Context, data any) bool {
 		Field:  field,
 		Name:   c.Name,
 	}
-	return !field.IsRequired(requiredCtx) && !(&RequiredValidator{}).Validate(requiredCtx)
+	return c.Found == walk.ElementNotFound && !field.IsRequired(requiredCtx)
 }
 
 func (v *validator) processAddedErrors(ctx *Context, parentPath *walk.Path, c *walk.Context, validator Validator) {

validation/validator_test.go

@@ -264,6 +264,16 @@ func TestValidate(t *testing.T) {
 				},
 			},
 		},
+		{
+			desc: "absent_nullable_not_required",
+			options: &Options{
+				Data:     map[string]any{},
+				Language: lang.New().GetDefault(),
+				Rules: RuleSet{
+					{Path: "property", Rules: List{String(), Nullable()}},
+				},
+			},
+		},
 		{
 			desc: "nil_delete_from_parent",
 			options: &Options{
@@ -291,7 +301,8 @@ func TestValidate(t *testing.T) {
 					{Path: "property", Rules: List{Required(), Nullable()}},
 				},
 			},
-			wantData: map[string]any{"property": nil}},
+			wantData: map[string]any{"property": nil},
+		},
 		{
 			desc: "root_array",
 			options: &Options{