public async void Delete() { Mock <ILogger <AirTransportRepository> > loggerMoc = AirTransportRepositoryMoc.GetLoggerMoc(); ApplicationDbContext context = AirTransportRepositoryMoc.GetContext(); var repository = new AirTransportRepository(loggerMoc.Object, context); AirTransport entity = new AirTransport(); context.Set <AirTransport>().Add(entity); await context.SaveChangesAsync(); await repository.Delete(entity.AirlineId); AirTransport modifiedRecord = await context.Set <AirTransport>().FirstOrDefaultAsync(); modifiedRecord.Should().BeNull(); }