public void Get_All_Users_Equal_To_GetAll() { //Arrange var options = new DbContextOptionsBuilder <ApplicationDbContext>() .UseInMemoryDatabase(databaseName: "Get_All_Users").Options; using (var ctx = new ApplicationDbContext(options)) { ctx.ApplicationUsers.Add(new ApplicationUser { Id = "228", UserName = "******" }); ctx.ApplicationUsers.Add(new ApplicationUser { Id = "3332", UserName = "******" }); ctx.SaveChanges(); } //Act using (var ctx = new ApplicationDbContext(options)) { var appUserService = new ApplicationUserService(ctx); var users = appUserService.GetAll(); //Assert Assert.AreEqual(users.Count(), 2); } }