自动锁定SUT

Question

我已经阅读了Mark Seeman 关于自动模拟的文章,我现在正在编写一个基于该文章的可重复使用的windsor容器.

我执行Mark的文章(基本上直接复制)

主要工作是在AutoMoqResolver课堂上完成的.只要类依赖于接口,这将提供模拟:

public class AutoMoqResolver : ISubDependencyResolver
{
    private readonly IKernel kernel;

    public AutoMoqResolver(IKernel kernel)
    {
        this.kernel = kernel;
    }

    public bool CanResolve(
        CreationContext context,
        ISubDependencyResolver contextHandlerResolver,
        ComponentModel model,
        DependencyModel dependency)
    {
        return dependency.TargetType.IsInterface;
    }

    public object Resolve(
        CreationContext context,
        ISubDependencyResolver contextHandlerResolver,
        ComponentModel model,
        DependencyModel dependency)
    {
        var mockType = typeof(Mock<>).MakeGenericType(dependency.TargetType);
        return ((Mock)this.kernel.Resolve(mockType)).Object;
    }
}

将AutoMoqResolver被添加到使用以下实施的容器IWindsorInstaller接口:

public class AutoMockInstaller<T> : IWindsorInstaller
{
    public void Install(
        IWindsorContainer container,
        IConfigurationStore store)
    {
        container.Kernel.Resolver.AddSubResolver(
            new AutoMoqResolver(container.Kernel));

        container.Register(Component.For(typeof(Mock<>)));

        container.Register(Classes
            .FromAssemblyContaining<T>()
            .Pick()
            .WithServiceSelf()
            .LifestyleTransient());
    }
}

然后我的容器只运行安装程序,它就可以自动为单元测试中的任何接口依赖项提供模拟:

public class AutoMockContainer<T> : WindsorContainer
{
    public AutoMockContainer()
    {
        // simply run the auto-mock installer
        this.Install(new AutoMockInstaller<T>());
    }
}

超!

我已经测试了这个,并且我的依赖项被自动地模拟了,所以我然后将它应用于一些真正的代码.这是当我意识到解决方案对我没有帮助时,因为我在测试课时倾向于遵循这种模式.我的具体问题是我希望能够自动模拟SUT本身,以验证SUT上的一个方法是从另一个方法调用的.

我的代码需要测试

我将通过一个例子来解释自己.我正在开发MVC代码,我使用以下一般模式支持不引人注目的AJAX:

public Class ExampleController : Controller
{
    private IService service;

    public ExampleController(IService service)
    {
        this.service = service;
    }

    public PartialViewResult DoSomethingWithAjax()
    {
        this.PerformTask();

        return this.PartialView();
    }

    public RedirectToRouteResult DoSomethingWithoutAjax()
    {
        this.PerformTask();

        return this.RedirectToAction("SomeAction");
    }

    protected virtual void PerformTask()
    {
        // do something here
    }
}

我的测试模式

所以为了验证PerformTask()方法是从DoSomethingWithAjax()or 调用的DoSomethingWithoutAjax(),我定义了一个TestableExampleController像这样的新类:

public class TestableExampleController : ExampleController
{
    public TestableExampleController(IService service) : base(service)
    {
    }

    public virtual void PerfomTaskPublic()
    {
        base.PerfomTask();
    }

    protected override void PerformTask()
    {
        this.PerformTaskPublic();
    }
}

然后我可以使用TestableExampleController我的SUT,以便通过以下测试:

[TestMethod]
public void DoSomethingAjax_Calls_PerformTask()
{
    //// Arrange
    // create a mock TestableExampleController
    var controllerMock = new Mock<TestableExampleController>();
    controllerMock.CallBase = true;

    // use the mock controller as the SUT
    var sut = controllerMock.Object;

    //// Act
    sut.DoSomethingAjax();

    //// Assert
    controllerMock.Verify(x => x.PerformTaskPublic(), Times.Once());
}

我的问题

重构此测试以使用我的AutoMockContainer类这样不起作用:

[TestMethod]
public void DoSomethingAjax_Calls_PerformTask()
{
    //// Arrange
    // create a container
    var container = new AutoMockContainer<TestableExampleController>();

    // resolve a mock SUT using the container
    var controllerMock = container.Resolve<Mock<TestableExampleController>>();
    controllerMock .CallBase = true;

    // use the mock controller as the SUT
    var sut = controllerMock.Object;

    //// Act
    sut.DoSomethingAjax();

    //// Assert
    controllerMock.Verify(x => x.PerformTaskPublic(), Times.Once());
}

测试无法创建实例,Mock<TestableExampleController>因为它无法找到无参数构造函数.

无法实例化类的代理:MyNamespace.TestableExampleController.找不到无参数构造函数.参数名称:constructorArguments

我建议的解决方案

理想情况下,我想实现一个包装类,可以在容器中注册以自动为任何组件提供模拟:

public class ComponentWrapper<T> where T : class
{
    public ComponentWrapper(Mock<T> componentMock)
    {
        componentMock.CallBase = true;
        this.ComponentMock = componentMock;
    }

    public Mock<T> ComponentMock { get; private set; }

    public T Component
    {
        get { return this.ComponentMock.Object;  }
    }
}

我希望能够编写以下通过的测试:

[TestMethod]
public void DoSomethingAjax_Calls_PerformTask()
{
    //// Arrange
    // create a container
    var container = new AutoMockContainer<TestableExampleController>();

    // resolve a ComponentWrapper using the container
    var wrapper = container.Resolve<ComponentWrapper<TestableExampleController>>();

    //// Act
    // call a method using the component
    wrapper.Component.DoSomethingAjax();

    //// Assert
    // verify a method call using the mock
    wrapper.ComponentMock.Verify(x => x.PerformTaskPublic(), Times.Once());
}

我不能完全理解如何实现这一目标,而且我花了大部分时间摆弄新的ISubDependencyResolver实现,但我无法让它工作.

希望我的问题很明确,答案实际上相对简单？

Answer 1

事实证明,AutoFixture.AutoMoq将完全符合我的要求,所以感谢TrueWill指出我正确的方向.

以下简单测试将通过:

[TestMethod]
public void Run_Calls_DoSomethingProtected()
{
    //// Arrange
    // AutoMoqCustomization allows AutoFixture to 
    // be used an an auto-mocking container
    var fixture = new Fixture().Customize(new AutoMoqCustomization());

    // simply ask the fixture to create a mock
    var sutMock = fixture.Create<Mock<TestableDummySystem>>();

    //// Act
    // exercise the mock object
    sutMock.Object.Run();

    //// Assert
    // this verification passes!
    sutMock.Verify(x => x.DoSomethingProtectedPublic());
}