public async Task DeleteShippingMethodShouldDelete() { var options = new DbContextOptionsBuilder <WHMSDbContext>().UseInMemoryDatabase(databaseName: Guid.NewGuid().ToString()).Options; using var context = new WHMSDbContext(options); var mockInventoryService = new Mock <IInventoryService>(); var service = new ShippingService(context, mockInventoryService.Object); var shippingService = "FedEx"; var carrier = new Carrier { Name = shippingService }; context.Carriers.Add(carrier); var shipping = new ShippingMethod { Carrier = carrier, CarrierId = carrier.Id, Name = shippingService }; context.ShippingMethods.Add(shipping); await context.SaveChangesAsync(); await service.DeleteShippingMethodAsync(shipping.Id); var shippingMethodDB = context.ShippingMethods.FirstOrDefault(); Assert.Null(shippingMethodDB); }