public void NonExistingUserContainsUsersForSubchannelTest()
    {
      ITvCardContext ctx = new TvCardContext();

      IUser u1 = new User("u1", false, 1);
      u1.SubChannel = 2;
      ctx.Add(u1);

      Assert.IsFalse(ctx.ContainsUsersForSubchannel(1), "user with subchannel found");
    }