Nunit 测试 MVC 站点

我在尝试对 MVC 站点进行单元测试时遇到了一些问题：我需要运行大量 ASP.NET 环境（生成 httpcontexts、会话、cookie、会员资格等）才能进行全面测试一切。

即使测试一些不太前端的东西也需要会员资格才能正常工作，而且手工欺骗这一切是很挑剔的。

有没有办法在 NUnit 测试中启动应用程序池？这似乎是最简单的方法。

如果编写正确，您不需要有真实的上下文、真实的会话、cookie 等。MVC 框架默认提供了一个可以模拟/存根的 HttpContext。我建议使用像 Moq 或 Rhino Mocks 这样的模拟框架，并创建一个 MockHttpContext 类，该类创建一个模拟上下文，其中包含您需要测试设置的所有属性。这是一个模拟 HttpContext，它使用Moq http://code.google.com/p/moq/

/// <summary>
/// Mocks an entire HttpContext for use in unit tests
/// </summary>
public class MockHttpContextBase
{
    /// <summary>
    /// Initializes a new instance of the <see cref="MockHttpContextBase"/> class.
    /// </summary>
    public MockHttpContextBase() : this(new Mock<Controller>().Object, "~/")
    {
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="MockHttpContextBase"/> class.
    /// </summary>
    /// <param name="controller">The controller.</param>
    public MockHttpContextBase(Controller controller) : this(controller, "~/")
    {
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="MockHttpContextBase"/> class.
    /// </summary>
    /// <param name="url">The URL.</param>
    public MockHttpContextBase(string url) : this(new Mock<Controller>().Object, url)
    {              
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="MockHttpContextBase"/> class.
    /// </summary>
    /// <param name="controller">The controller.</param>
    /// <param name="url">The URL.</param>
    public MockHttpContextBase(ControllerBase controller, string url)
    {
        HttpContext = new Mock<HttpContextBase>();
        Request = new Mock<HttpRequestBase>();
        Response = new Mock<HttpResponseBase>();
        Output = new StringBuilder();

        HttpContext.Setup(x => x.Request).Returns(Request.Object);
        HttpContext.Setup(x => x.Response).Returns(Response.Object);
        HttpContext.Setup(x => x.Session).Returns(new FakeSessionState());

        Request.Setup(x => x.Cookies).Returns(new HttpCookieCollection());
        Request.Setup(x => x.QueryString).Returns(new NameValueCollection());
        Request.Setup(x => x.Form).Returns(new NameValueCollection());
        Request.Setup(x => x.ApplicationPath).Returns("~/");
        Request.Setup(x => x.AppRelativeCurrentExecutionFilePath).Returns(url);
        Request.Setup(x => x.PathInfo).Returns(string.Empty);

        Response.Setup(x => x.Cookies).Returns(new HttpCookieCollection());
        Response.Setup(x => x.ApplyAppPathModifier(It.IsAny<string>())).Returns((string path) => path);
        Response.Setup(x => x.Write(It.IsAny<string>())).Callback<string>(s => Output.Append(s));

        var requestContext = new RequestContext(HttpContext.Object, new RouteData());
        controller.ControllerContext = new ControllerContext(requestContext, controller);
    }

    /// <summary>
    /// Gets the HTTP context.
    /// </summary>
    /// <value>The HTTP context.</value>
    public Mock<HttpContextBase> HttpContext { get; private set; }

    /// <summary>
    /// Gets the request.
    /// </summary>
    /// <value>The request.</value>
    public Mock<HttpRequestBase> Request { get; private set; }

    /// <summary>
    /// Gets the response.
    /// </summary>
    /// <value>The response.</value>
    public Mock<HttpResponseBase> Response { get; private set; }

    /// <summary>
    /// Gets the output.
    /// </summary>
    /// <value>The output.</value>
    public StringBuilder Output { get; private set; }
}

/// <summary>
/// Provides Fake Session for use in unit tests
/// </summary>
public class FakeSessionState : HttpSessionStateBase
{
    /// <summary>
    /// backing field for the items in session
    /// </summary>
    private readonly Dictionary<string, object> _items = new Dictionary<string, object>();

    /// <summary>
    /// Gets or sets the <see cref="System.Object"/> with the specified name.
    /// </summary>
    /// <param name="name">the key</param>
    /// <returns>the value in session</returns>
    public override object this[string name]
    {
        get
        {
            return _items.ContainsKey(name) ? _items[name] : null;
        }
        set
        {
            _items[name] = value;
        }
    }
}

您可以进一步添加一些内容，例如 HTTP 标头集合，但希望它能够演示您可以做什么。

To use

var controllerToTest = new HomeController();
var context = new MockHttpContextBase(controllerToTest);

// do stuff that you want to test e.g. something goes into session

Assert.IsTrue(context.HttpContext.Session.Count > 0); 

对于会员提供商或其他提供商，您发现了一些难以测试的东西。我将抽象接口背后的提供者的使用，以便您可以在测试依赖于该接口的组件时为该接口提供一个假的。然而，您在对使用提供程序的接口的具体实现进行单元测试时仍然会遇到麻烦，但是您的里程可能会因您想要/必须在单元测试和代码覆盖率方面走多远而有所不同。