如何对ViewComponent.Invoke()进行单元测试？

Question

在ViewComponentobject中,HttpContext并且User是只读属性.

如何对这样的组件进行单元测试？

我正在使用MSTest Freamwork.

以下属性用于我的代码中

1. 曲奇饼
2. 会议
3. 用户(System.Security.Principal)

---

public ViewViewComponentResult Invoke()
{
    var vm = new SummaryViewModel();
    if (User.Identity is ClaimsIdentity identity && identity.IsAuthenticated)
    {
        vm.IsAuthenticated = true;
        vm.UserName = identity.Claims.FirstOrDefault(c => c.Type == "UserName").Value;
        vm.PhotoUrl = identity.Claims.FirstOrDefault(c => c.Type == "FacePicture").Value;
    }
    return View(vm);
}

[TestMethod]
public void UserSummaryVcTest()
{
    var component = new UserSummaryViewComponent();
    var model = component.Invoke().ViewData.Model as SummaryViewModel;
    Assert.AreEqual("UserName", model.UserName);
} 

Answer 1

根据源代码，ViewComponent依赖于ViewComponentContext.ViewContext公开那些只读属性，进而访问HttpContext. 这是您模拟所需值的切入点。

[TestMethod]
public void UserSummaryVcTest() {

    // Arrange
    var expected = "Username value";
    var httpContext = new DefaultHttpContext(); //You can also Mock this
    //...then set user and other required properties on the httpContext as needed

    var viewContext = new ViewContext();
    viewContext.HttpContext = httpContext;
    var viewComponentContext = new ViewComponentContext();
    viewComponentContext.ViewContext = viewContext;

    var viewComponent = new UserSummaryViewComponent();
    viewComponent.ViewComponentContext = viewComponentContext;

    //Act
    var model = viewComponent.Invoke().ViewData.Model as SummaryViewModel;

    //Assert
    Assert.AreEqual(expected, model.UserName);
}