public void Contructor_Should_NotThrowArgumentNullException_IfPassedDbContextIsNotNull()
        {
            // Arrange
            var validDbContext = new Mock <ICarSystemEfDbContext>();
            var carSystemDbContextSaveChanges = new CarSystemDbContextSaveChanges(validDbContext.Object);

            // Act & Assert
            Assert.That(carSystemDbContextSaveChanges, Is.Not.Null);
        }
        public void SaveChanges_Should_CallSaveChangesOnce()
        {
            // Arrange
            var validDbContext = new Mock <ICarSystemEfDbContext>();
            var carSystemDbContextSaveChanges = new CarSystemDbContextSaveChanges(validDbContext.Object);

            // Act
            carSystemDbContextSaveChanges.SaveChanges();

            // Assert
            validDbContext.Verify(u => u.SaveChanges(), Times.Once);
        }