public void RepoEnsureICanAddGamerToDB() { List <Gamer> expected = new List <Gamer> { new Gamer { GamerID = 0 } }; Gamer me = new Gamer { GamerID = 1 }; _gamerSet.Object.AddRange(expected); ConnectMocksToDataStore(expected); _gamerSet.Setup(o => o.Add(It.IsAny <Gamer>())).Callback((Gamer g) => expected.Add(g)); bool actual = _repo.AddGamer(me); Assert.IsTrue(actual); Assert.AreEqual(2, expected.Count); }