public async Task GetAllByUsernameShouldHaveCountTwo() { var list = new List <Vote>(); var mockRepository = new Mock <IDeletableEntityRepository <Vote> >(); mockRepository .Setup(x => x.AllAsNoTracking()) .Returns(list.AsQueryable()); mockRepository .Setup(x => x.AddAsync(It.IsAny <Vote>())) .Callback((Vote vote) => list.Add(vote)); var service = new VotesService(mockRepository.Object); await service.CreateAsync(new CreateVoteDTO { ForUserId = "a", VoteValue = true, VoterId = "b", }); await service.CreateAsync(new CreateVoteDTO { ForUserId = "a", VoteValue = true, VoterId = "c", }); Assert.Equal(2, service.GetAllByUserId <VotesViewModel>("a").Count()); }