func TestPolymorphicHasOneAssociation(t *testing.T) {
	pet := Pet{Name: "hasone", Toy: Toy{Name: "toy-has-one"}}

	if err := DB.Create(&pet).Error; err != nil {
		t.Fatalf("errors happened when create: %v", err)
	}

	CheckPet(t, pet, pet)

	// Find
	var pet2 Pet
	DB.Find(&pet2, "id = ?", pet.ID)
	DB.Model(&pet2).Association("Toy").Find(&pet2.Toy)
	CheckPet(t, pet2, pet)

	// Count

	pets2 := []Pet{{Name: "pet-has-many-append-1-1"}, {Name: "pet-has-many-append-1-1"}}

	if err := DB.Model(&user2).Association("Pets").Append(&pets2); err != nil {
		t.Fatalf("Error happened when append pet, got %v", err)
	}

	for _, pet := range pets2 {
		pet := pet
		if pet.ID == 0 {
			t.Fatalf("Pet's ID should be created")
		}

		user.Pets = append(user.Pets, &pet)
	}

		}}

		if err := DB.Create(&pets).Error; err != nil {
			t.Fatalf("errors happened when create: %v", err)
		}

		var petIDs []uint
		for _, pet := range pets {
			petIDs = append(petIDs, pet.ID)
			CheckPet(t, pet, pet)
		}

		var pets2 []Pet
		DB.Preload("Toy").Find(&pets2, "id IN ?", petIDs)
		for idx, pet := range pets2 {
			CheckPet(t, pet, pets[idx])
		}
	})

			}
		}
	})

	t.Run("Pets", func(t *testing.T) {
		if len(user.Pets) != len(expect.Pets) {
			t.Fatalf("pets should equal, expect: %v, got %v", len(expect.Pets), len(user.Pets))
		}

		sort.Slice(user.Pets, func(i, j int) bool {
			return user.Pets[i].ID > user.Pets[j].ID
		})

		sort.Slice(expect.Pets, func(i, j int) bool {
			return expect.Pets[i].ID > expect.Pets[j].ID
		})

	} else {
		sort.Slice(users2[2].Pets, func(i, j int) bool {
			return users2[2].Pets[i].ID < users2[2].Pets[j].ID
		})

		for _, pet := range users2[2].Pets[0:2] {
			if pet.Toy.Name != "" {
				t.Errorf("No toy should for user %v's pet %v but got %v", 3, pet.Name, pet.Toy.Name)
			}
		}

		CheckPet(t, *users2[2].Pets[2], *users[2].Pets[2])
	}
}

func TestPreloadEmptyData(t *testing.T) {

	DB.Joins("inner join pets on pets.user_id = users.id AND pets.name = @Name", user.Pets[0]).Where("users.name = ?", user.Name).First(&users6)
	if len(users6) != 1 {
		t.Errorf("should find one users using left join with conditions, but got %v", len(users6))
	}

	dryDB := DB.Session(&gorm.Session{DryRun: true})

	}

	r = dryDB.Table("(?) as u, (?) as p", DB.Model(&User{}).Select("name"), DB.Model(&Pet{}).Select("name")).Find(&User{}).Statement
	if !regexp.MustCompile("SELECT \\* FROM \\(SELECT .name. FROM .users. WHERE .users.\\..deleted_at. IS NULL\\) as u, \\(SELECT .name. FROM .pets. WHERE .pets.\\..deleted_at. IS NULL\\) as p WHERE .u.\\..deleted_at. IS NULL").MatchString(r.Statement.SQL.String()) {

)

// User has one `Account` (has one), many `Pets` (has many) and `Toys` (has many - polymorphic)
// He works in a Company (belongs to), he has a Manager (belongs to - single-table), and also managed a Team (has many - single-table)
// He speaks many languages (many to many) and has many friends (many to many - single-table)
// His pet also has one Toy (has one - polymorphic)
// NamedPet is a reference to a named `Pet` (has one)
type User struct {
	gorm.Model

			References: []Reference{{"ID", "User", "UserID", "Account", "", true}},
		},
		{
			Name: "Pets", Type: schema.HasMany, Schema: "User", FieldSchema: "Pet",
			References: []Reference{{"ID", "User", "UserID", "Pet", "", true}},
		},
		{
			Name: "Toys", Type: schema.HasMany, Schema: "User", FieldSchema: "Toy",

	result.Pets = append(user.Pets, result.Pets...)
	result.Team = append(user.Team, result.Team...)
	result.Friends = append(user.Friends, result.Friends...)

	sort.Slice(result.Pets, func(i, j int) bool {
		return result.Pets[i].ID < result.Pets[j].ID
	})