使用Moq验证使用不同对象状态的方法调用

Question

最近我Moq在一个C#项目中发现了图书馆(4.5.21)非常有趣的行为.以下是我要测试的课程.

public class Order
{
    public string State { get; set; }
}

public interface IOrderService
{
    Task UpdateOrderAsync(Order order);
}

public class Program
{
    public async Task RunAsync(IOrderService orderService)
    {
        var order = new Order();

        order.State = "new";
        await orderService.UpdateOrderAsync(order);

        order.State = "open";
        await orderService.UpdateOrderAsync(order);
    }
}

以下是我的TestClass:

[TestMethod]
public async Task TestMethod()
{
    var mock = new Mock<IOrderService>();
    await new Program().RunAsync(mock.Object);

    mock.Verify(x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "new")), Times.Once);
    mock.Verify(x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "open")), Times.Once);
}

我得到以下输出:

Moq.MockException:
Expected invocation on the mock once, but was 0 times: x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "new"))


Configured setups:
x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "new")), Times.Once
x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "open")), Times.Once

Performed invocations:
IOrderService.UpdateOrderAsync(Order<State:open>)
IOrderService.UpdateOrderAsync(Order<State:open>)

我希望我每次都可以使用不同Verify的方法调用该方法.关于我做错了什么的任何想法？OnceobjectState

谢谢!

Answer 1

这看起来与这篇文章非常相似

基本上，这是因为在调用第一个验证时，模拟持有的引用（对于特定调用）已将其 State 属性更改为“open”（就在第二次调用之前）。这可以通过将 Order 类更改为结构来证明，以确保模拟捕获对象的副本而不是对对象本身的引用。

编辑：为了获得完整的答案，并且上面的帖子使用了现在已过时的 Expect，这里是一个通过测试：

var mock = new Mock<IOrderService>(MockBehavior.Loose);

var newCalled = false;
var openCalledBeforeNew = false;

mock.Setup(x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "new"))).Callback(() => newCalled = !openCalledBeforeNew).Returns(Task.FromResult((object)null));
mock.Setup(x => x.UpdateOrderAsync(It.Is<Order>(o => o.State == "open"))).Callback(() => openCalledBeforeNew = newCalled).Returns(Task.FromResult((object)null));

await new Program().RunAsync(mock.Object);

Assert.IsTrue(newCalled);
Assert.IsTrue(openCalledBeforeNew);