@Override
    public AdminUserDO getUserByUsername(String username) {
        return userMapper.selectByUsername(username);
    }
@Test
    public void testGetUserByUsername() {
        // mock 数据
        AdminUserDO dbUser = randomAdminUserDO();
        userMapper.insert(dbUser);
        // 准备参数
        String username = dbUser.getUsername();

        // 调用
        AdminUserDO user = userService.getUserByUsername(username);
        // 断言
        assertPojoEquals(dbUser, user);
    }