模拟非虚拟发布模型属性和方法

Question

我将人模型类定义为：

public class PersonModel
{
    public bool SelectionSubmitted = false;

    public bool ShowValidationSummary = false;

    public string Name;

    public string Get()
    {            
        //actual implementation return some value from the db
        return string.Empty;
    }
}

控制器实现如下：

class HomeController : Controller
{
    [HttpGet]
    public ActionResult Index(PersonModel model)
    {
        if (model.SelectionSubmitted && !ValidateSelections(model))
        {
            model.ShowValidationSummary = true;
        }

        return View("Index", model.Get());
    }

    private bool ValidateSelections(PersonModel model)
    {
        if(model.Name == "")
        {
            ModelState.AddModelError("EmptyPersonName", "Person name cannot be null");
        }
        return ModelState.IsValid;
    }       
}

测试类和方法定义为：

[TestClass]
public class ChildWithoutPlacementControllerTest
{
    private readonly Mock<PersonModel> _mockPersonModel;

    public ChildWithoutPlacementControllerTest()
    {
        _mockPersonModel = new Mock<PersonModel>();
    }

    [TestMethod]
    public void GivenPerson_WhenSearchingForFutureBirthDate_ThenValidationMessageShouldBeShown()
    {
        //Arrange
        HomeController controller = new HomeController();
        _mockPersonModel.Setup(x => x.Get()).Returns(It.IsAny<string>());
        _mockPersonModel.SetupGet(x => x.Name).Returns(string.Empty);
        _mockPersonModel.SetupGet(x => x.SelectionSubmitted).Returns(true);

        //Act
        controller.Index(_mockPersonModel.Object);

        //Assert
        var isShowSummarySetToTrue = _mockPersonModel.Object.ShowValidationSummary;
        Assert.IsTrue(isShowSummarySetToTrue);
    }
}

我想要实现的是将SelectionSubmitted和Name属性分别模拟为true和string.Empty以及SetupGet类的Get方法，并检查测试是否返回对象已将 ShowValidationSummary 设置为 true。

但是，我发现我无法设置非虚拟属性名称。

我做错了什么还是有什么方法可以在不更改实现代码的情况下做到这一点？

Answer 1

我做错了什么

这似乎是XY problem。

有什么方法可以在不改变实现代码的情况下做到这一点

在这种情况下确实不需要起订量。您可以使用继承来制作要在测试中使用的假模型。假模型将覆盖与数据库紧密耦合的方法。 （稍后会详细介绍）

​​>

public class FakePerson : PersonModel {
    public new string Get() {
        return string.Empty; //Not calling the base Get
    }
}

然后可以重构测试以使用假模型并按预期完成。

[TestMethod]
public void GivenPerson_WhenSearchingForFutureBirthDate_ThenValidationMessageShouldBeShown() {
    //Arrange
    var fakePersonModel = new FakePerson() {
        Name = string.Empty,
        SelectionSubmitted = true
    };
    var controller = new HomeController();

    //Act
    controller.Index(fakePersonModel);

    //Assert
    var isShowSummarySetToTrue = fakePersonModel.ShowValidationSummary;
    Assert.IsTrue(isShowSummarySetToTrue);
}

除此之外，如果实际的 Get 实现按照您在此处所述进行，那么您的模型似乎可以做很多事情

实际的实现从数据库中返回一些值

考虑将该功能重构为服务（单一职责原则/关注点分离）

public interface IPersonModelService {
    string Get(PersonModel person);
}

public class PersonModelService : IPersonModelService {

    public string Get(PersonModel person) {
        //actual implementation return some value from the db
    }
}

并尽可能保持模型精简。还可以考虑将这些公共字段重构为公共属性。

public class PersonModel {
    public bool SelectionSubmitted { get; set; }

    public bool ShowValidationSummary { get; set; }

    public string Name { get; set; }

}

控制器将依赖于服务抽象

class HomeController : Controller {
    private IPersonModelService service;

    public HomeController(IPersonModelService service) {
        this.service = service;
    }

    [HttpGet]
    public ActionResult Index(PersonModel model) {
        if (model.SelectionSubmitted && !ValidateSelections(model)) {
            model.ShowValidationSummary = true;
        }

        return View("Index", service.Get(model));
    }

    private bool ValidateSelections(PersonModel model) {
        if (model.Name == "") {
            ModelState.AddModelError("EmptyPersonName", "Person name cannot be null");
        }
        return ModelState.IsValid;
    }
}

现在可以单独完成测试。

[TestMethod]
public void GivenPerson_WhenSearchingForFutureBirthDate_ThenValidationMessageShouldBeShown() {
    //Arrange
    var model = new PersonModel() {
        Name = string.Empty,
        SelectionSubmitted = true
    };

    var serviceMock = new Mock<IPersonModelService>();
    serviceMock.Setup(_ => _.Get(It.IsAny<PersonModel>())).Returns(string.Empty);
    var controller = new HomeController(serviceMock.Object);

    //Act
    controller.Index(model);

    //Assert
    var isShowSummarySetToTrue = model.ShowValidationSummary;
    Assert.IsTrue(isShowSummarySetToTrue);
}