t.Errorf("json marshal is not empty slice, got %v", string(r))
	}
}

func TestPreloadGoroutine(t *testing.T) {
	var wg sync.WaitGroup

	wg.Add(10)
	for i := 0; i < 10; i++ {
		go func() {
			defer wg.Done()
			var user2 []User
			tx := DB.Where("id = ?", 1).Session(&gorm.Session{})

			if err := tx.Preload("Team").Find(&user2).Error; err != nil {
				t.Error(err)
			}
		}()
	}
	wg.Wait()
}