public async Task WhenGetUserAsyncCalled_ReturnsAuser(int id)
        {
            //ARRANGE
            List <AppUser> users = new List <AppUser>
            {
                new AppUser
                {
                    Id              = 1,
                    City            = "Alabama",
                    CountryOfOrigin = "FakeCountry",
                    Gender          = "Fake",
                    Interests       = "Fake it",
                    Name            = "Faker McGee",
                    DateOfBirth     = new System.DateTime(1969, 4, 20)
                },
                new AppUser {
                    Id              = 2,
                    City            = "Washington DC",
                    CountryOfOrigin = "FakeCountry",
                    Gender          = "Fake",
                    Interests       = "Fake it",
                    Name            = "Faker McGee",
                    DateOfBirth     = new System.DateTime(1969, 4, 20)
                },
                new AppUser
                {
                    Id              = 3,
                    City            = "Berlin",
                    CountryOfOrigin = "FakeCountry",
                    Gender          = "Fake",
                    Interests       = "Fake it",
                    Name            = "Faker McGee",
                    DateOfBirth     = new System.DateTime(1969, 4, 20)
                },
                new AppUser
                {
                    Id              = 4,
                    City            = "Vienna",
                    CountryOfOrigin = "FakeCountry",
                    Gender          = "Fake",
                    Interests       = "Fake it",
                    Name            = "Faker McGee",
                    DateOfBirth     = new System.DateTime(1969, 4, 20)
                },
                new AppUser
                {
                    Id              = 5,
                    City            = "Paris",
                    CountryOfOrigin = "FakeCountry",
                    Gender          = "Fake",
                    Interests       = "Fake it",
                    Name            = "Faker McGee",
                    DateOfBirth     = new System.DateTime(1969, 4, 20)
                },
                new AppUser
                {
                    Id              = 6,
                    City            = "Boston",
                    CountryOfOrigin = "FakeCountry",
                    Gender          = "Fake",
                    Interests       = "Fake it",
                    Name            = "Faker McGee",
                    DateOfBirth     = new System.DateTime(1969, 4, 20)
                },
            };

            mockRepo.Setup(x => x.GetUserAsync(It.IsAny <int>())).ReturnsAsync(users[2]);

            var service = new AppUserService(mockRepo.Object, config.CreateMapper());
            //ACT
            var result = await service.GetUserAsync(id);

            //ASSERT
            Assert.NotNull(result);
            Assert.AreEqual("Berlin", users[2].City);
        }