public async Task DeleteElement_Success()
{
var item = new Author()
{
Name = "name", Surname = "surname", BornDate = "01-01-1970", Country = "TEST"
};
await db.AddItemAsync(item);
// reload element to get item with given Id
item = db.GetItemsAsync().Result.FirstOrDefault();
await db.DeleteItemAsync(item);
Assert.AreEqual(0, db.GetItemsAsync().Result.Count);
}
