c# - 单元测试 Controller 中抛出的异常

Question

我目前正在进行单元测试，当发送无效的表单集合数据时会引发错误。

异常是在 HttpPost Index ActionResult 方法中抛出的，如下所示:

    [HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult Index(FormCollection formCollection, PaymentType payType, string progCode)
    {
        ActionResult ar = redirectFromButtonData(formCollection, payType, progCode);

        if (ar != null)
        {
            return ar;
        }
        else
        {
            throw new Exception("Cannot redirect to payment form from cohort decision - Type:[" +  payType.ToString()  + "] Prog:[" +  Microsoft.Security.Application.Encoder.HtmlEncode(progCode) + "]");
        }
    }

到目前为止，我已经编写了一个成功命中异常的测试(我已经通过启用代码覆盖验证了这一点，我一直在使用它来查看每个单独测试正在执行的代码)但目前测试失败，因为我没有尚未定义一种测试是否已抛出异常的方法，可以在下面找到此测试的代码:

    [TestMethod]
    public void Error_Is_Thrown_If_HVM_FormCollection_Data_Is_Incorrect()
    {
        var formCollection = new FormCollection();
        formCollection.Add("__RequestVerificationToken", "__RequestVerificationToken");
        formCollection.Add("invalid - invalid", "invalid- invalid");


        var payType = new PaymentType();
        payType = PaymentType.deposit;

        var progCode = "hvm";

        var mocks = new MockRepository();

        var httpRequest = mocks.DynamicMock<HttpRequestBase>();
        var httpContext = mocks.DynamicMock<HttpContextBase>();
        controller.ControllerContext = new ControllerContext(httpContext, new RouteData(), controller);
        mocks.ReplayAll();

        httpRequest.Expect(r => r.Url).Return(new Uri("http://localhost:8080/hvm/full/self/")).Repeat.Any();

        httpContext.Expect(c => c.Request).Return(httpRequest).Repeat.Any();

        var result = controller.Index(formCollection, payType, progCode);
    }

我研究过使用 [ExpectedException(typeof(Exception)] 注释可以在这种情况下使用吗？

Answer 1

我冒昧地更改了您的测试代码，稍微符合 rhino-mocks 的最新功能。不再需要创建 MockRepository , 你可以使用静态类 MockRepository并调用GenerateMock<> .我还移动了您的 SuT(被测系统)实例低于您模拟的规范。

Nunit 示例(与 MSTest 相比，我对 Nunit 的体验更好。主要是因为 Nunit 发布更频繁并且具有更可靠的功能集。同样，不确定它是否适用于 TFS，但这应该不难发现) .

[Test] // Nunit
[ExpectedException(typeof(Exception)) // NOTE: it's wise to throw specific 
// exceptions so that you prevent false-positives! (another "exception" 
// might make the test pass while it's a completely different scenario)
public void Error_Is_Thrown_If_HVM_FormCollection_Data_Is_Incorrect()
{
    var formCollection = new FormCollection();
    formCollection.Add("__RequestVerificationToken", "__RequestVerificationToken");
    formCollection.Add("invalid - invalid", "invalid- invalid");

    var payType = new PaymentType();
    payType = PaymentType.deposit;

    var progCode = "hvm";

    var httpRequest = MockRepository.GenerateMock<HttpRequestBase>();
    var httpContext = MockRepository.GenerateMock<HttpContextBase>();

    // define behaviour
    httpRequest.Expect(r => r.Url).Return(new Uri("http://localhost:8080/hvm/full/self/")).Repeat.Any();
    httpContext.Expect(c => c.Request).Return(httpRequest).Repeat.Any();

    // instantiate SuT (system under test)
    controller.ControllerContext = new ControllerContext(httpContext, new RouteData(), controller);

    // Test the stuff, and if nothing is thrown then the test fails
    var result = controller.Index(formCollection, payType, progCode);
}

与 MStest 的处理几乎相同，只是您需要更老一点地定义预期的异常。

[TestMethod] // MStest
public void Error_Is_Thrown_If_HVM_FormCollection_Data_Is_Incorrect()
{
    try
    {
        var formCollection = new FormCollection();
        formCollection.Add("__RequestVerificationToken", "__RequestVerificationToken");
        formCollection.Add("invalid - invalid", "invalid- invalid");

        var payType = new PaymentType();
        payType = PaymentType.deposit;

        var progCode = "hvm";

        var httpRequest = MockRepository.GenerateMock<HttpRequestBase>();
        var httpContext = MockRepository.GenerateMock<HttpContextBase>();

        // define behaviour
        httpRequest.Expect(r => r.Url).Return(new Uri("http://localhost:8080/hvm/full/self/")).Repeat.Any();
        httpContext.Expect(c => c.Request).Return(httpRequest).Repeat.Any();

        // instantiate SuT (system under test)
        controller.ControllerContext = new ControllerContext(httpContext, new RouteData(), controller);

        // Test the stuff, and if nothing is thrown then the test fails
        var result = controller.Index(formCollection, payType, progCode);
    }
    catch (Exception)
    {
        Assert.Pass();
    }
    Assert.Fail("Expected exception Exception, was not thrown");
}

如果您使该部分正常工作，您可以通过提供的链接重构它以提高可重用性:Assert exception from NUnit to MS TEST .