問(wèn)題描述

我正在尋找如何模擬一個(gè)在第二次調(diào)用它時(shí)返回不同值的方法.例如，像這樣:

I'm looking to find out how I can mock a method that returns a different value the second time it is called to the first time. For example, something like this:

public interface IApplicationLifetime
{
    int SecondsSinceStarted {get;}
}

[Test]
public void Expected_mock_behaviour()
{
    IApplicationLifetime mock = MockRepository.GenerateMock<IApplicationLifetime>();

    mock.Expect(m=>m.SecondsSinceStarted).Return(1).Repeat.Once();
    mock.Expect(m=>m.SecondsSinceStarted).Return(2).Repeat.Once();

    Assert.AreEqual(1, mock.SecondsSinceStarted);
    Assert.AreEqual(2, mock.SecondsSinceStarted);
}

有什么可以讓這成為可能嗎?除了為實(shí)現(xiàn)狀態(tài)機(jī)的 getter 實(shí)現(xiàn) sub 之外?

Is there anything that makes this possible? Besides implementing a sub for the getter that implements a state machine?

推薦答案

您可以使用 .WhenCalled 方法截取返回值.請(qǐng)注意，您仍然需要通過(guò) .Return 方法提供一個(gè)值，但是如果 ReturnValue 從方法調(diào)用中被更改，Rhino 將忽略它:

You can intercept return values with the .WhenCalled method. Note that you still need to provide a value via the .Return method, however Rhino will simply ignore it if ReturnValue is altered from the method invocation:

int invocationsCounter = 1;
const int IgnoredReturnValue = 10;
mock.Expect(m => m.SecondsSinceLifetime)
    .WhenCalled(mi => mi.ReturnValue = invocationsCounter++)
    .Return(IgnoredReturnValue);

Assert.That(mock.SecondsSinceLifetime, Is.EqualTo(1));
Assert.That(mock.SecondsSinceLifetime, Is.EqualTo(2));

再深入研究一下，似乎 .Repeat.Once() 確實(shí) 在這種情況下確實(shí)有效，并且可以用于實(shí)現(xiàn)相同的結(jié)果:

Digging around a bit more, it seems that .Repeat.Once() does indeed work in this case and can be used to achieve the same result:

mock.Expect(m => m.SecondsSinceStarted).Return(1).Repeat.Once();
mock.Expect(m => m.SecondsSinceStarted).Return(2).Repeat.Once();
mock.Expect(m => m.SecondsSinceStarted).Return(3).Repeat.Once();

將在連續(xù)調(diào)用時(shí)返回 1、2、3.

Will return 1, 2, 3 on consecutive calls.

這篇關(guān)于Rhino Mocks - 通過(guò)多次調(diào)用模擬其返回值更改(即使傳遞相同的參數(shù))的方法的文章就介紹到這了，希望我們推薦的答案對(duì)大家有所幫助，也希望大家多多支持html5模板網(wǎng)！