public void testToStandardSeconds() {
        Days test = Days.days(2);
        Seconds expected = Seconds.seconds(2 * 24 * 60 * 60);
        assertEquals(expected, test.toStandardSeconds());
        
        try {
            Days.MAX_VALUE.toStandardSeconds();
            fail();
        } catch (ArithmeticException ex) {
            // expected
        }
    }