unit-testing - 最小起订量，如何使用私有(private)构造函数最小起订量对象？

Question

我有这个类层次结构

public class Order
{  
    private Client _client;
    public virtual Client { get => _client; }

    private OrderNumber _orderNumber;
    public virtual OrderNumber OrderNumber { get => _orderNumber; }

    private ShippingDetails _shippingDetails;
    public virtual ShippingDetails ShippingDetails { get => _shippingDetails; }

    private IList<Product> _products;
    protected internal virtual IEnumerable<Product> Products { get => _products; }


    public Order() { }

    public virtual void CreateDraftForClient(int id)
    {
         /// => business rule validation of value 

         _client= new Client(id);

          /// => event     
     }
}

public class Client
{
    private int _id;
    public virtual int Id { get => _id; }

    private Client() { }
    protected internal Client(int id) 
    {
        SetId(id);
    }

    private void SetId(int id)
    {
        _id = id; 
    }
}

并希望创建一个完全初始化的订单模拟

 clientMock = new Mock<Client>();
 clientMock.SetupGet(prop => prop.Client).Returns(1);

 orderMock = new Mock<Order>();
 orderMock.SetupGet(prop => prop.Client).Returns(orderMock.Object);

异常:

Message: System.AggregateException : One or more errors occurred. (Can not instantiate proxy of class: Client. Could not find a parameterless constructor.) (The following constructor parameters did not have matching fixture data: eRxTestSetup testSetup)
---- Castle.DynamicProxy.InvalidProxyConstructorArgumentsException : Can not instantiate proxy of class: Client. Could not find a parameterless constructor.
---- The following constructor parameters did not have matching fixture data: eRxTestSetup testSetup

有什么方法可以在不改变客户端结构的情况下做到这一点？或者，如果没有，我还有哪些其他选择？

Answer 1

Order 没有简单的方法可以根据其当前定义进行模拟。

通过将所需的参数传递给模拟，尝试通过 protected 构造函数创建模拟

int id = 1;
var clientMock = new Mock<Client>(id);
clientMock.SetupGet(prop => prop.Id).Returns(id);

var orderMock = new Mock<Order>();
orderMock.SetupGet(prop => prop.Client).Returns(clientMock.Object);