@Test
  public void testServiceCustomCommandScriptInheritance() throws Exception {
    // Test custom command script determination in parent
    ServiceInfo service = metaInfo.getService(STACK_NAME_HDP, "2.0.7", "HDFS");

    CustomCommandDefinition ccd = findCustomCommand("RESTART", service);
    Assert.assertEquals("scripts/restart_parent.py",
            ccd.getCommandScript().getScript());

    ccd = findCustomCommand("YET_ANOTHER_PARENT_SRV_COMMAND", service);
    Assert.assertEquals("scripts/yet_another_parent_srv_command.py",
            ccd.getCommandScript().getScript());

    Assert.assertEquals(2, service.getCustomCommands().size());

    // Test custom command script inheritance
    service = metaInfo.getService(STACK_NAME_HDP, "2.0.8", "HDFS");
    Assert.assertEquals(3, service.getCustomCommands().size());

    ccd = findCustomCommand("YET_ANOTHER_PARENT_SRV_COMMAND", service);
    Assert.assertEquals("scripts/yet_another_parent_srv_command.py",
            ccd.getCommandScript().getScript());

    // Test custom command script override
    service = metaInfo.getService(STACK_NAME_HDP, "2.0.8", "HDFS");

    ccd = findCustomCommand("RESTART", service);
    Assert.assertEquals("scripts/restart_child.py",
            ccd.getCommandScript().getScript());

    ccd = findCustomCommand("YET_ANOTHER_CHILD_SRV_COMMAND", service);
    Assert.assertEquals("scripts/yet_another_child_srv_command.py",
            ccd.getCommandScript().getScript());
  }
Make sure global mapping is avaliable when global.xml is
in the path.
ambari-server/src/test/java/org/apache/ambari/server/api/services/AmbariMetaInfoTest.java