public void CheckAssignmentExistAfterDelete() { //Arrange Assignment assignment1 = new Assignment() { Id = 66, Name = "test", Description = "unit" }; Assignment assignment2 = new Assignment() { Id = 77, Name = "test", Description = "unit" }; var options = new DbContextOptionsBuilder <Context>() .UseInMemoryDatabase(databaseName: "UsersDirectoryMVC") .Options; using (var context = new Context(options)) { //Act var assignmentRepository = new AssignmentRepository(context); assignmentRepository.AddAssignment(assignment1); assignmentRepository.AddAssignment(assignment2); assignmentRepository.DeleteAssignment(66); var gerAssignment1 = assignmentRepository.GetAssignment(66); var gerAssignment2 = assignmentRepository.GetAssignment(77); //Assert gerAssignment1.Should().BeNull(); gerAssignment2.Should().Equals(assignment2); } }