@Test
public void testList() throws RemotingException {

    mockChannel = mock(Channel.class);
    given(mockChannel.getAttribute("telnet.service")).willReturn(null);
    registerProvider(DemoService.class.getName(), new DemoServiceImpl(), DemoService.class);
    String result = list.telnet(mockChannel, "");
    assertEquals("PROVIDER:\r\norg.apache.dubbo.qos.legacy.service.DemoService\r\n", result);
}