def test_necessario(self):
        self.assertTrue(self.seg_p)

        seg_p2 = itau.registros.SegmentoP()
        self.assertFalse(seg_p2.necessario())

        seg_p2.controle_banco = 33
        self.assertFalse(seg_p2.necessario())

        seg_p2.vencimento_titulo = 10102012
        self.assertTrue(seg_p2.necessario())
def test_subclass_delayed(self):
        class X(Structure):
            pass
        self.assertEqual(sizeof(X), 0)
        X._fields_ = [("a", c_int)]

        class Y(X):
            pass
        self.assertEqual(sizeof(Y), sizeof(X))
        Y._fields_ = [("b", c_int)]

        class Z(X):
            pass

        self.assertEqual(sizeof(X), sizeof(c_int))
        self.assertEqual(sizeof(Y), sizeof(c_int)*2)
        self.assertEqual(sizeof(Z), sizeof(c_int))
        self.assertEqual(X._fields_, [("a", c_int)])
        self.assertEqual(Y._fields_, [("b", c_int)])
        self.assertEqual(Z._fields_, [("a", c_int)])