public void CreateAuthenticatedPrincipalWithEmptyRoles()
        {
            var p = Principal.Create("Test",
                                     new Claim(ClaimTypes.Name, "test"));

            var roles = Principal.CreateRoles(new string[] { });

            p.Identities.First().AddClaims(roles);

            Assert.IsTrue(p.Identity.IsAuthenticated);
            Assert.AreEqual <string>(p.Identities.First().AuthenticationType, "Test");
            Assert.AreEqual <int>(p.Identities.Count(), 1);
            Assert.AreEqual <int>(p.Identities.First().Claims.Count(), 1);
        }