public void RemoveProject() { DbContextOptions <ApplicationContext> options = new DbContextOptionsBuilder <ApplicationContext>() .UseInMemoryDatabase(Guid.NewGuid().ToString()) .EnableSensitiveDataLogging() .Options; var dbProvider = new DatabaseProvider(options); Employe employe1 = new Employe { FirstName = "Anton", MiddleName = "Antonovich", LastName = "Antonov" }; dbProvider.AddEmploye(employe1); var project = new Project { Name = "Ololo", Premium = 2500, SupplierEmploye = employe1 }; dbProvider.AddProject(project); dbProvider.DeleteProject(project.Id); Assert.Throws(typeof(InvalidOperationException), new TestDelegate(() => dbProvider.GetProject(project.Id))); }