Fix extra updates when Append associations for many2many

association.go

@@ -30,19 +30,44 @@ func (association *Association) Append(values ...interface{}) *Association {
 	scope := association.Scope
 	field := association.Field
 
+	createJoinTable := func(reflectValue reflect.Value) {
+		var value = reflectValue.Interface()
+		if reflectValue.Kind() != reflect.Ptr {
+			reflectPtr := reflect.New(reflectValue.Type())
+			reflectPtr.Elem().Set(reflectValue)
+			value = reflectPtr.Interface()
+		}
+
+		if scope.New(value).PrimaryKeyZero() {
+			scope.NewDB().Save(value)
+		}
+
+		relationship := association.Field.Relationship
+		association.setErr(relationship.JoinTableHandler.Add(relationship.JoinTableHandler, scope.NewDB(), scope.Value, value))
+
+		result := reflect.ValueOf(value)
+		fieldElemType := field.Field.Type().Elem()
+		if result.Type().AssignableTo(fieldElemType) {
+			field.Set(reflect.Append(field.Field, result))
+		} else if result.Type().Elem().AssignableTo(fieldElemType) {
+			field.Set(reflect.Append(field.Field, result.Elem()))
+		}
+	}
+
 	for _, value := range values {
-		reflectvalue := reflect.Indirect(reflect.ValueOf(value))
-		if reflectvalue.Kind() == reflect.Struct {
-			field.Set(reflect.Append(field.Field, reflectvalue))
-		} else if reflectvalue.Kind() == reflect.Slice {
-			field.Set(reflect.AppendSlice(field.Field, reflectvalue))
+		reflectValue := reflect.Indirect(reflect.ValueOf(value))
+
+		if reflectValue.Kind() == reflect.Struct {
+			createJoinTable(reflectValue)
+		} else if reflectValue.Kind() == reflect.Slice {
+			for i := 0; i < reflectValue.Len(); i++ {
+				createJoinTable(reflectValue.Index(i))
+			}
 		} else {
 			association.setErr(errors.New("invalid association type"))
 		}
 	}
-	scope.Search.Select(association.Column)
-	scope.callCallbacks(scope.db.parent.callback.updates)
-	return association.setErr(scope.db.Error)
+	return association
 }
 
 func (association *Association) Delete(values ...interface{}) *Association {
@@ -230,7 +255,7 @@ func toQueryMarks(primaryValues [][]interface{}) string {
 
 	for _, primaryValue := range primaryValues {
 		var marks []string
-		for _,_ = range primaryValue {
+		for _, _ = range primaryValue {
 			marks = append(marks, "?")
 		}
 

association_test.go

@@ -160,7 +160,7 @@ func TestManyToMany(t *testing.T) {
 
 	languageA := Language{Name: "AA"}
 	DB.Save(&languageA)
-	DB.Model(&User{Id: user.Id}).Association("Languages").Append(languageA)
+	DB.Model(&User{Id: user.Id}).Association("Languages").Append(&languageA)
 
 	languageC := Language{Name: "CC"}
 	DB.Save(&languageC)