Question

我在编写一些单元测试时遇到了一些困难，无法测试我创建的自定义ModelBinder。我正在尝试单元测试的ModelBinder是我发布的here的JsonDictionaryModelBinder。

我遇到的问题是使用Moq进行模拟所有设置。由于HttpContextBase没有被正确模拟，我一直得到Null Exceptions。我想。

有人可以帮我弄清楚我在做什么吗？

以下是我试图编写的单元测试示例：

[TestMethod()]
public void BindModelTest()
{
    JsonDictionaryModelBinder target = new JsonDictionaryModelBinder();

    NameValueCollection nameValueCollection = new NameValueCollection() {
        {"First", "1"},
        {"Second", "2"},
        {"Name", "Chris"},
        {"jsonValues", "{id: 200, name: 'Chris'}"}
    };

    HttpContextBase httpContext = MockHelper.FakeHttpContext(HttpVerbs.Post, nameValueCollection);

    ControllerContext controllerContext =
        new ControllerContext(new RequestContext(httpContext, new RouteData()), new Mock<Controller>().Object);


    Predicate<string> predicate = propertyName => (propertyName == "jsonValues");
    ModelBindingContext bindingContext = new ModelBindingContext()
    {
        Model = null,
        ModelType = typeof(JsonDictionary),
        ModelState = new ModelStateDictionary(),
        PropertyFilter = predicate,
        ValueProvider = new Dictionary<string, ValueProviderResult>() { { "foo", null } }
    };

    //object expected = null; // TODO: Initialize to an appropriate value
    var actual = target.BindModel(controllerContext, bindingContext) as JsonDictionary;

    Assert.IsNotNull(actual);

    Assert.AreEqual("Chris", actual["name"]);
    //Assert.AreEqual(expected, actual);
    Assert.Inconclusive("Verify the correctness of this test method.");
}

这是上面使用的“FakeHttpContext”方法：

public static class MockHelper
{
    public static HttpContextBase FakeHttpContext(HttpVerbs verbs, NameValueCollection nameValueCollection)
    {
        var httpContext = new Mock<HttpContextBase>();

        var request = new Mock<HttpRequestBase>();
        request.Setup(c => c.Form).Returns(nameValueCollection);
        request.Setup(c => c.QueryString).Returns(nameValueCollection);

        var response = new Mock<HttpResponseBase>();
        var session = new Mock<HttpSessionStateBase>();
        var server = new Mock<HttpServerUtilityBase>();
        httpContext.Setup(c => c.Request).Returns(request.Object);

        var u = verbs.ToString().ToUpper();
        httpContext.Setup(c => c.Request.RequestType).Returns(
            verbs.ToString().ToUpper()
        );

        httpContext.Setup(c => c.Response).Returns(response.Object);
        httpContext.Setup(c => c.Server).Returns(server.Object);
        httpContext.Setup(c => c.User.Identity.Name).Returns("testclient");
        return httpContext.Object;
    }
}

Answer 1

罪魁祸首就是这条线：

httpContext.Setup(c => c.Request.RequestType).Returns(
                verbs.ToString().ToUpper()
            );

这在技术上是Request对象上的第二个Setup，它正在擦除原始的Setup，即使你在对象层次结构中“过去”它。我不确定这是否是Moq中的错误或期望的行为，我之前也遇到过这种情况，并且还没有找到它。

您可以通过将该行移动到您在上面设置请求的位置并直接设置它来解决问题，而不是通过httpContext。所以，

request.Setup(c => c.RequestType).Returns(verbs.ToString().ToUpper());

我还注意到您声明的“var u”未被使用;）

如何使用Moq对自定义ModelBinder进行单元测试？

1 个答案: