单元测试模拟 ControllerContext HttpContext 没有为类型“Microsoft.AspNetCore.Mvc.View...ITempDataDictionaryFactory”注册服务

Question

在我的测试项目中，我将 xUnit 与 Moq 一起使用。

现在我想在 controller 中对这些代码进行单元测试：

[HttpGet]
[AllowAnonymous]
public async Task<IActionResult> Login(string returnUrl = null)
{
    await HttpContext.SignOutAsync(IdentityConstants.ExternalScheme);

    ViewData["ReturnUrl"] = returnUrl;
    return View();
}

如您所见，它使用HttpContext的SignOutAsync 。

我尝试了很多解决方案，例如ASP.NET MVC - 单元测试，mocking HttpContext 没有使用任何模拟框架，但对我不起作用，因为我无权访问HttpRequestBase

使用 Moq，我试图模拟这个HttpContext ，所以我尝试了这个：

public static Mock<HttpContext> GenerateFakeHttpContext()
{
   var mockHttpContext = new Mock<HttpContext>();
   var authServiceMock = new Mock<IAuthenticationService>();
   authServiceMock.Setup(_ => _.SignOutAsync(
                                   It.IsAny<HttpContext>(), 
                                   It.IsAny<string>(), 
                                   It.IsAny<AuthenticationProperties>()))
       .Returns(Task.FromResult((object)null));

   var serviceProviderMock = new Mock<IServiceProvider>();

   serviceProviderMock.Setup(_ => _.GetService(typeof(IAuthenticationService)))
           .Returns(authServiceMock.Object);

   mockHttpContext.Setup(x => x.RequestServices)
           .Returns(serviceProviderMock.Object);

   return mockHttpContext;
}

灵感来自这个问题： MSTest: Unit Testing HttpContext.SignoutAsync for the logout ，经过多项研究。

测试方法是这样的：

public async Task Login_ShouldSignOutToClearCoockies_WhenReturnUrlIsNullOrNotNull()
{
    //Arrange
    _sutAccountController
    .ControllerContext.HttpContext = TestsHelper.GenerateFakeHttpContext().Object;

    //Act
    var result = await _sutAccountController.Login(null);

    //Assert
    result.Should().NotBeNull();
}

但在运行时我得到这个异常：

   Duration: 367 ms

  Message: 
System.InvalidOperationException : No service for type 'Microsoft.AspNetCore.Mvc.ViewFeatures.ITempDataDictionaryFactory' has been registered.

  Stack Trace: 
ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider, Type serviceType)
ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)
Controller.get_TempData()
Controller.View(String viewName, Object model)
Controller.View(String viewName)
Controller.View()
AccountController.Login(String returnUrl) line 38
AccountControllerTests.Login_ShouldSignOutToClearCoockies_WhenReturnUrlIsNullOrNotNull() line 46
--- End of stack trace from previous location ---

如果有更好的方法来模拟HttpContext 。

谢谢。

Answer 1

我终于找到了 mocking controller TempData 的解决方案

来源： MSTest 中 ASP.NET 核心中的 Mocking TempData

var tempData = new Microsoft.AspNetCore.Mvc.ViewFeatures
.TempDataDictionary(httpContext, Mock.Of<Microsoft.AspNetCore.Mvc.ViewFeatures.ITempDataProvider>());
tempData["ReturnUrl"] = "";

_sutController.ControllerContext.HttpContext = httpContext;
_sutController.TempData = tempData