public async Task AddTimeslotAsync_Database_test1()
        {
            using var connection = Database_init();
            var options = new DbContextOptionsBuilder <ClinicDbContext>().UseSqlite(connection).Options;

            using var context = new ClinicDbContext(options);
            var repo = new ClinicRepository(context, new NullLogger <ClinicRepository>());

            var timeslot = new Domain.Models.Timeslot(new DateTime(2020, 12, 20, 8, 0, 0))
            {
                Appointment = new Domain.Models.Appointment(5, "idiot can't find his stethoscope")
                {
                    PatientId = 7,
                    DoctorId  = 4
                },
                Id       = 9,
                DoctorId = 4
            };

            await repo.AddTimeslotAsync(timeslot);

            var timeslotActual = context.Timeslots.Find(9);

            Assert.Equal(timeslotActual.Id, timeslot.Id);
            Assert.Equal(timeslotActual.DoctorId, timeslot.DoctorId);
            Assert.Equal(timeslotActual.AppointmentId, timeslot.Appointment?.Id);
            Assert.Equal(timeslotActual.Start, timeslot.Start);
            Assert.Equal(timeslotActual.End, timeslot.End);
        }
        public void AddTimeslot_Database_test2()
        {
            using var connection = Database_init();
            var options = new DbContextOptionsBuilder <ClinicDbContext>().UseSqlite(connection).Options;

            using var context = new ClinicDbContext(options);
            var repo = new ClinicRepository(context, new NullLogger <ClinicRepository>());

            var timeslot = new Domain.Models.Timeslot(new DateTime(2020, 12, 20, 8, 0, 0))
            {
                Id       = 9,
                DoctorId = 4
            };

            repo.AddTimeslot(timeslot);

            var timeslotActual = context.Timeslots.Find(9);

            Assert.Equal(timeslotActual.Id, timeslot.Id);
            Assert.Equal(timeslotActual.DoctorId, timeslot.DoctorId);
            Assert.Equal(timeslotActual.Start, timeslot.Start);
            Assert.Equal(timeslotActual.End, timeslot.End);
            Assert.Null(timeslotActual.Appointment);
        }