Question

我是测试和模拟的新手，我正在尝试编写一个测试，以确保我的验证逻辑正确设置ModelState错误。

我所看到的是 controller.ControllerContext.HttpContext.Request 在我第一次检查时设置，但每次 Request 为空。

这导致MVC源中* ValueProviderDictionary *类的 PopulateDictionary 方法中出现空引用异常，因为在该方法中多次访问请求对象，而不确保请求不为null。

我正在研究如何克服我到目前为止遇到的一些问题时找到的几种技术和助手，所以在这一点上我有点不确定我可能在哪里引入了这个问题。

我在这里错误地使用了模拟对象吗？

测试失败

//Test
public void Test_FooController_OnActionExecuting_ShouldMapStateToAFooModel()
{
    //Arrange
    DataAccessFactoryMocks.MockAllDaos();

    var controller = new FooController();

    var testFormCollection = new NameValueCollection();
    testFormCollection.Add("foo.CustomerID", "3");
    testFormCollection.Add("_fooForm", SerializationUtils.Serialize(new FooModel()));

    var mockHttpContext = new MockHttpContext(controller, "POST", testFormCollection, null);

    //Accessor used to run the protected OnActionExecuting method in my controller
    var accessor = new FooControllerAccessor(controller);

    //Request is set, assertion passes
    Assert.IsNotNull(controller.ControllerContext.HttpContext.Request.Form);

    //Request is null when accessing the property a second time, assertion fails
    Assert.IsNotNull(controller.ControllerContext.HttpContext.Request.QueryString);

    //Act
    accessor.OnActionExecuting(new ActionExecutingContext(controller.ControllerContext, MockRepository.GenerateStub<ActionDescriptor>(), new Dictionary<string, object>()));

    //Assert
    Assert.That(controller.ModelState.IsValid == false);
}

测试助手

//Test helper to create httpcontext and set controller context accordingly
public class MockHttpContext
{
    public HttpContextBase HttpContext { get; private set; }
    public HttpRequestBase Request { get; private set; }
    public HttpResponseBase Response { get; private set; }
    public RouteData RouteData { get; private set; }

    public MockHttpContext(Controller onController)
    {
        //Setup the common context components and their relationships
        HttpContext = MockRepository.GenerateMock<HttpContextBase>();
        Request = MockRepository.GenerateMock<HttpRequestBase>();
        Response = MockRepository.GenerateMock<HttpResponseBase>();

        //Setup the context, request, response relationship
        HttpContext.Stub(c => c.Request).Return(Request);
        HttpContext.Stub(c => c.Response).Return(Response);

        Request.Stub(r => r.Cookies).Return(new HttpCookieCollection());
        Response.Stub(r => r.Cookies).Return(new HttpCookieCollection());

        Request.Stub(r => r.QueryString).Return(new NameValueCollection());
        Request.Stub(r => r.Form).Return(new NameValueCollection());

        //Apply the context to the suppplied controller
        var rc = new RequestContext(HttpContext, new RouteData());
        onController.ControllerContext = new ControllerContext(rc, onController);
    }

    public MockHttpContext(Controller onController, string httpRequestType, NameValueCollection form, NameValueCollection querystring)
    {
    //Setup the common context components and their relationships
    HttpContext = MockRepository.GenerateMock<HttpContextBase>();
    Request = MockRepository.GenerateMock<HttpRequestBase>();
    Response = MockRepository.GenerateMock<HttpResponseBase>();

    //Setup request type based on parameter value
    Request.Stub(r => r.RequestType).Return(httpRequestType);

    //Setup the context, request, response relationship
    HttpContext.Stub(c => c.Request).Return(Request);
    HttpContext.Stub(c => c.Response).Return(Response);

    Request.Stub(r => r.Cookies).Return(new HttpCookieCollection());
    Response.Stub(r => r.Cookies).Return(new HttpCookieCollection());

    Request.Stub(r => r.QueryString).Return(querystring);
    Request.Stub(r => r.Form).Return(form);

    //Apply the context to the suppplied controller
    var rc = new RequestContext(HttpContext, new RouteData());
    onController.ControllerContext = new ControllerContext(rc, onController);
    }
}

使用MvcContrib.TestHelper进行工作测试

    public void Test_FooController_OnActionExecuting_ShouldMapStateToAFooModel()
    {
        //Arrange
        DataAccessFactoryMocks.MockAllDaos();

        TestControllerBuilder builder = new TestControllerBuilder();

        builder.Form.Add("fooModel.CustomerID", "3");

        builder.HttpContext.Request.Stub(r => r.RequestType).Return("POST");

        FooController controller = builder.CreateController<FooController>();

        var accessor = new FooControllerAccessor(controller);

        //Act
        accessor.OnActionExecuting(new ActionExecutingContext(controller.ControllerContext, MockRepository.GenerateStub<ActionDescriptor>(), new Dictionary<string, object>()));

        //Assert
        Assert.IsFalse(controller.ModelState.IsValid);
    }

Answer 1

我建议您使用优秀的MVCContrib TestHelper对使用Rhino Mocks的ASP.NET MVC控制器进行单元测试。您将看到单元测试的大幅简化和可读性的提高。

Answer 2

我从你的问题中理解的是，ControllerContext的模拟也可以被存根对象替换，因为目标不是测试ControllerContext行为。另外，我不确定你为什么需要一个FooControllerAccessor，而你唯一关心的是断言ModelState，所以我把它留在了这里：

public void Test_FooController_OnActionExecuting_ShouldMapStateToAFooModel()
{
    // Arrange
    var action = new FooController()
        .Action("index")
        .RequestData(new Dictionary<string, object>()
        {
            {"foo.CustomerID", 3},
            {"_fooForm", new FooModel()}
        });

    //Act
    var modelState = action.ValidateRequest();

    //Assert
    Assert.That(modelState.IsValid == false);
}

要使用此代码，您应该安装Xania.AspNet.Simulator（在编写v1.4.0-beta5时）适用于Mvc4和Mvc5

PM ＆gt; install-package Xania.AspNet.Simulator -Pre

有关更多示例，请查看以下内容：

模拟MVC ControllerContext请求的问题

2 个答案: