public void RemoveUnexistingOrder()
{
// Arrange
var order = new Order();
var item = new OrderDetails {Article = "Test", Count = 1, Price = 0.99};
// Act
order.RemoveItem(item);
// Assert by attribute
}
public void AddingOrderItemToOrder()
{
// Arrange
var order = new Order();
var item = new OrderDetails {Article = "Test", Count = 2, Price = 0.99};
// Act
order.AddItem(item);
// Assert
Assert.AreEqual(order.Items.Count(), 1);
Assert.AreEqual(order.Amount, 0.99);
}