public void IF_HttpContext_is_null_SHOULD_return_new_session_each_time() { //Arrange _httpContext = null; _mockHttpContextAccessor.With(x => x.HttpContext, _httpContext); //Act var result1 = Sut.CreateSession(); var result2 = Sut.CreateSession(); //Assert Assert.That(result1.Id.Length, Is.EqualTo(Guid.NewGuid().ToString().Length)); Assert.That(result1.UserId, Is.Null); Assert.That(result2.Id.Length, Is.EqualTo(Guid.NewGuid().ToString().Length)); Assert.That(result2.UserId, Is.Null); Assert.That(result1.Id, Is.Not.EqualTo(result2.Id)); }