Stub or Mock, as far as possible, the Asp.Net MVC controller HttpContext and also System.Web.HttpContext.Current

gistfile1.txt

  public partial class HttpRequestOverridableWrapper : HttpRequestWrapper
  {
      readonly string appVirtualDir;
      public HttpRequestOverridableWrapper(HttpRequest httpRequest, string appVirtualDir)
          : base(httpRequest)
      {
          this.appVirtualDir = appVirtualDir;
      }

      public override string ApplicationPath { get { return appVirtualDir; } }

  }

  public static class MockHttpContextHelperV3
  {
      public static T WithHttpContextAndRoutes<T>(this T @this, Action<RouteCollection> mvcApplicationRoutesRegistration = null, string requestUrl = null, string query = "", string appVirtualPath = "/", HttpApplication applicationInstance = null) where T : Controller
      {
          string requestUrl1 = requestUrl ?? @this.GetType().Name;
          HttpApplication applicationInstance1 = applicationInstance ?? new HttpApplication();
          return @this.WithHttpContextAndRoutes(
                          MockHttpContextBase(
                              FakeHttpContextCurrent(appVirtualPath, requestUrl1, query, applicationInstance1),
                              appVirtualPath),
                          mvcApplicationRoutesRegistration);
      }

      public static T WithHttpContextAndRoutes<T>(this T @this, HttpContextBase httpContextBase, Action<RouteCollection> mvcApplicationRoutesRegistration) where T : Controller
      {
          var routes = new RouteCollection();
          var routeData = routes.GetRouteData(httpContextBase) ?? new RouteData();
          mvcApplicationRoutesRegistration = mvcApplicationRoutesRegistration ?? TypicalMvcRouteConfig.RegisterRoutes;
          mvcApplicationRoutesRegistration(routes);
          @this.Url = new UrlHelper(new RequestContext(httpContextBase, routeData), routes);
          @this.ControllerContext = new ControllerContext(httpContextBase, routeData, @this);
          return @this;
      }

      public static HttpContextBase MockHttpContextBase(HttpContext httpContext, string appVirtualDir = "/")
      {
          var context = new Mock<HttpContextBase>();
          context.Setup(ctx => ctx.Request).Returns(new HttpRequestOverridableWrapper(httpContext.Request,appVirtualDir));
          context.Setup(ctx => ctx.Response).Returns(new HttpResponseWrapper(httpContext.Response));
          context.Setup(ctx => ctx.User).Returns(httpContext.User);
          context.Setup(ctx => ctx.Session).Returns(new HttpSessionStateWrapper(httpContext.Items["AspSession"] as HttpSessionState));
          context.Setup(ctx => ctx.Items).Returns(httpContext.Items);
          context.Setup(ctx => ctx.Server).Returns(MockServerUtility(appVirtualDir).Object);
          context.Setup(ctx => ctx.Application).Returns(new Mock<HttpApplicationStateBase>().Object);
          return context.Object;
      }

      static HttpContext FakeHttpContextCurrent(string appVirtualPath, string requestUrl, string query,
                                                HttpApplication applicationInstance)
      {
          var httpContext = FakeHttpContext(requestUrl, query, appVirtualPath, applicationInstance ?? new HttpApplication());
          HttpContext.Current = httpContext;
          return httpContext;
      }

      public static Mock<HttpServerUtilityBase> MockServerUtility(string appVirtualDir)
      {
          var server = new Mock<HttpServerUtilityBase>();
          server.Setup(s => s.MachineName).Returns(Environment.MachineName);
          server.Setup(s => s.MapPath(It.IsAny<string>()))
                .Returns((string s) =>
                {
                    var s1 = s.StartsWith("~")
                                 ? ".\\" + s.Substring(1)
                                 : s.StartsWith(appVirtualDir)
                                       ? ".\\" + s.Substring(appVirtualDir.Length)
                                       : s;
                    return s1.Replace('/', '\\');
                });
          return server;
      }

      public static HttpContext FakeHttpContext(string requestUrl, string query, string appVirtualDir, HttpApplication applicationInstance)
      {
          var request = new HttpRequest("",
                                        new UriBuilder("http", "localhost", 80, appVirtualDir + requestUrl).Uri.ToString(),
                                        query);

          //request.Headers.Add("Referer",referer);Can't do this, throws a System.PlatformNotSupportedException : Operation is not supported on this platform 

          var response = new HttpResponse(new StringWriter());
          var httpContext = new HttpContext(request, response);
          httpContext.User = new WindowsPrincipal(WindowsIdentity.GetCurrent() ?? new WindowsIdentity("FakeWindowsIdentity"));
          var session = CreateSession();
          httpContext.Items["AspSession"] = session;
          httpContext.ApplicationInstance = applicationInstance;
          return httpContext;
      }

      public static HttpSessionState CreateSession()
      {
          var sessionContainer = new HttpSessionStateContainer("id", new SessionStateItemCollection(),
                                                               new HttpStaticObjectsCollection(), 10, true,
                                                               HttpCookieMode.AutoDetect,
                                                               SessionStateMode.InProc, false);

          return (HttpSessionState)typeof(HttpSessionState).GetConstructor(
              BindingFlags.NonPublic | BindingFlags.Instance,
              null, CallingConventions.Standard,
              new[] { typeof(HttpSessionStateContainer) },
              null)
                                                           .Invoke(new object[] { sessionContainer });
      }

  }