Creates HttpContext with Session to stub HttpContext.Current

HttpContextCurrentTests.cs

using System.IO;
using System.Reflection;
using System.Web;
using System.Web.SessionState;

using NUnit.Framework;

namespace Mvc.Tests
{
  [TestFixture]
  public class HttpContextCurrentTests
  {
    private HttpSessionState _sessionState;

    [SetUp]
    public void SetUp()
    {
      HttpContext.Current = CreateHttpContextCurrent();
      _sessionState = HttpContext.Current.Session;
    }

    private HttpContext CreateHttpContextCurrent()
    {
      var httpRequest = new HttpRequest(string.Empty, "http://someurl/", string.Empty);
      var stringWriter = new StringWriter();
      var httpResponce = new HttpResponse(stringWriter);
      var httpContext = new HttpContext(httpRequest, httpResponce);

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

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

      return httpContext;
    }
  }
}

Very, very good.
This code saved the day
Tks

God bless