@Override
    public List<MailAccountDO> getMailAccountList() {
        return mailAccountMapper.selectList();
    }
@Test
    public void testGetMailAccountList() {
        // mock 数据
        MailAccountDO dbMailAccount01 = randomPojo(MailAccountDO.class);
        mailAccountMapper.insert(dbMailAccount01);
        MailAccountDO dbMailAccount02 = randomPojo(MailAccountDO.class);
        mailAccountMapper.insert(dbMailAccount02);
        // 准备参数

        // 调用
        List<MailAccountDO> list = mailAccountService.getMailAccountList();
        // 断言
        assertEquals(2, list.size());
        assertPojoEquals(dbMailAccount01, list.get(0));
        assertPojoEquals(dbMailAccount02, list.get(1));
    }