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

		&Pet{Name: "pet-slice-append-1"},
		[]*Pet{{Name: "pet-slice-append-2-1"}, {Name: "pet-slice-append-2-2"}},
		&Pet{Name: "pet-slice-append-3"},
	)

	AssertAssociationCount(t, users, "Pets", 10, "After Append")

	// Replace -> same as append
	DB.Model(&users).Association("Pets").Replace(
		[]*Pet{{Name: "pet-slice-replace-1-1"}, {Name: "pet-slice-replace-1-2"}},

	} 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})

			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",

  public static <E extends @Nullable Object> SetView<E> union(
      final Set<? extends E> set1, final Set<? extends E> set2) {
    checkNotNull(set1, "set1");
    checkNotNull(set2, "set2");

    return new SetView<E>() {
      @Override
      public int size() {
        int size = set1.size();
        for (E e : set2) {
          if (!set1.contains(e)) {
            size++;
          }
        }
        return size;

              }
            });
  }

  public void testEquals() {
    SortedSet<String> set1 = ImmutableSortedSet.of("one");
    SortedSet<String> set2 = ImmutableSortedSet.of("two");
    new EqualsTester()
        .addEqualityGroup(set1, wrap(set1), wrap(set1))
        .addEqualityGroup(set2, wrap(set2))
        .testEquals();
  }

              }
            });
  }

  public void testEquals() {
    SortedMultiset<String> set1 = ImmutableSortedMultiset.of("one");
    SortedMultiset<String> set2 = ImmutableSortedMultiset.of("two");
    new EqualsTester()
        .addEqualityGroup(set1, wrap(set1), wrap(set1))
        .addEqualityGroup(set2, wrap(set2))
        .testEquals();
  }

              }
            });
  }

  public void testEquals() {
    SortedMultiset<String> set1 = ImmutableSortedMultiset.of("one");
    SortedMultiset<String> set2 = ImmutableSortedMultiset.of("two");
    new EqualsTester()
        .addEqualityGroup(set1, wrap(set1), wrap(set1))
        .addEqualityGroup(set2, wrap(set2))
        .testEquals();
  }

              }
            });
  }

  public void testEquals() {
    SortedSet<String> set1 = ImmutableSortedSet.of("one");
    SortedSet<String> set2 = ImmutableSortedSet.of("two");
    new EqualsTester()
        .addEqualityGroup(set1, wrap(set1), wrap(set1))
        .addEqualityGroup(set2, wrap(set2))
        .testEquals();
  }