@Test
public void testGreeting() throws Exception {

    Help help = new Help();
    String output = help.execute(Mockito.mock(CommandContext.class), new String[]{"greeting"});
    assertThat(output, containsString("COMMAND NAME"));
    assertThat(output, containsString("greeting"));
    assertThat(output, containsString("EXAMPLE"));
    assertThat(output, containsString("greeting dubbo"));
}