Unit test to mock ASP.NET Identity failed logon

Question

I'm writing a unit test using Moq and Microsoft's testing tools for an ASP.NET MVC 5 app that uses ASP.NET Identity. The test needs to simulate a logon failure in the Login POST action, such that it produces SignInStatus.Failure from the SignInManager.PasswordSignInAsync method of my AccountController:

[HttpPost]
[AllowAnonymous]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Login([Bind(Include = "Email,Password,RememberMe")] 
    LoginViewModel model, string returnUrl)
{
    var result = await SignInManager.PasswordSignInAsync(model.Email, model.Password, 
        model.RememberMe, shouldLockout: true);
    switch (result)
    {
        case SignInStatus.Success:
            return Redirect(returnUrl);
        case SignInStatus.LockedOut:
            return View("Lockout");
        case SignInStatus.RequiresVerification:
        case SignInStatus.Failure:
        default:
            ModelState.AddModelError("", "Invalid login attempt.");
            return View(model);
    }   
}

Here are the helper members/methods on my [TestClass]:

private Mock<HttpContextBase> _httpContextMock;
private Mock<HttpRequestBase> _httpRequestMock;
private Mock<HttpResponseBase> _httpResponseMock;
private MyApp.Controllers.AccountController _controller;
private Mock<ControllerContext> _controllerContextMock;

[TestInitialize]
public void SetupTests()
{
    // Set up Moq
    _httpContextMock = new Mock<HttpContextBase>();
    _httpRequestMock = new Mock<HttpRequestBase>();
    _httpResponseMock = new Mock<HttpResponseBase>();
    _controller = new AccountController();
    _controllerContextMock = new Mock<ControllerContext>();
}

private void SetContexts(IPrincipal user)
{
    _httpContextMock.Setup(x => x.Items).Returns(new Dictionary<string, object>());
    var sessionContainer = new HttpSessionStateContainer("id", new SessionStateItemCollection(),
        new HttpStaticObjectsCollection(), 10, true,
        HttpCookieMode.AutoDetect,
        SessionStateMode.InProc, false);
    //this adds aspnet session
    _httpContextMock.Object.Items["AspSession"] = typeof(HttpSessionState).GetConstructor(
            BindingFlags.NonPublic | BindingFlags.Instance,
            null, CallingConventions.Standard,
            new[] { typeof(HttpSessionStateContainer) },
            null)
        .Invoke(new object[] { sessionContainer });
    _httpContextMock.Setup(x => x.User).Returns(user);

    // https://stackoverflow.com/questions/674458/asp-net-mvc-unit-testing-controllers-that-use-urlhelper
    _httpRequestMock.SetupGet(x => x.ApplicationPath).Returns("/");
    _httpRequestMock.SetupGet(x => x.Url).Returns(new Uri("http://localhost/a", UriKind.Absolute));
    _httpRequestMock.SetupGet(x => x.ServerVariables).Returns(new NameValueCollection());

    _httpResponseMock.Setup(x => x.ApplyAppPathModifier(It.IsAny<string>())).Returns<string>(x => x);
    var routes = new RouteCollection();
    RouteConfig.RegisterRoutes(routes);
    var helper = new UrlHelper(new RequestContext(_httpContextMock.Object, new RouteData()), routes);

    _httpContextMock.SetupGet(x => x.Request).Returns(_httpRequestMock.Object);
    _httpContextMock.SetupGet(x => x.Response).Returns(_httpResponseMock.Object);

    // https://stackoverflow.com/questions/4066184/httpresponsebase-headers-are-empty-when-running-test
    _httpResponseMock.Setup(r => r.OutputStream).Returns(new MemoryStream());
    _httpResponseMock.Setup(r => r.Headers).Returns(new NameValueCollection());

    var userStore = new Mock<IUserStore<ApplicationUser>>();
    var userManager = new Mock<ApplicationUserManager>(userStore.Object);
    var authenticationManager = new Mock<IAuthenticationManager>();
    var signInManager = new Mock<ApplicationSignInManager>(userManager.Object, authenticationManager.Object);

    var data = new Dictionary<string, object>()
    {
        {"a", "b"} // fake whatever  you need here.
    };

    // https://stackoverflow.com/a/28574389/177416
    _controller = new AccountController(
        userManager.Object, signInManager.Object)
    {
        ControllerContext = new ControllerContext()
        {
            HttpContext = _httpContextMock.Object
        }
    }; 

    _controller.ControllerContext.HttpContext.Items["owin.Environment"] = data;
    _controller.Url = helper;
}

And here's my test method:

[TestMethod]
public async Task NoViewReturnedForFailedLogin()
{
    // Arrange
    var claimsIdentity = new ClaimsIdentity();
    claimsIdentity.AddClaim(new Claim(ClaimTypes.Name, "fake@fake.org"));
    var claimsPrincipal = new ClaimsPrincipal(claimsIdentity);
    SetContexts(claimsPrincipal);
    var vm = new LoginViewModel
    {
        Email = "faker@gmail.com",
        Password = "Faker9999!",
        RememberMe = false
    };

    _controllerContextMock.SetupGet(p => p.HttpContext.User.Identity.Name).Returns(vm.Email);
    _controllerContextMock.SetupGet(p => p.HttpContext.Request.IsAuthenticated).Returns(false);

    // Act
    var result = await _controller.Login(vm, "http://www.google.com") as RedirectToRouteResult;

    // Assert
    // ? What do I assert?
}

As you can see, I have mock userStore, userManager, authenticationManager, and signInManager. If I step through the Login action, result always returns SignInStatus.Success.

Is there a way to have it fail? What should the test assert?