@Test
  public void testComponentCommandScriptInheritance() throws Exception {
    // Test command script determination in parent
    ComponentInfo component = metaInfo.getComponent(STACK_NAME_HDP,
        "2.0.7", "HDFS", "HDFS_CLIENT");
    Assert.assertEquals("scripts/hdfs_client.py",
            component.getCommandScript().getScript());
    component = metaInfo.getComponent(STACK_NAME_HDP,
        "2.0.7", "HBASE", "HBASE_MASTER");
    Assert.assertEquals("scripts/hbase_master.py",
            component.getCommandScript().getScript());
    // Test command script inheritance
    component = metaInfo.getComponent(STACK_NAME_HDP,
        "2.0.8", "HBASE", "HBASE_MASTER");
    Assert.assertEquals("scripts/hbase_master.py",
            component.getCommandScript().getScript());
    // Test command script override
    component = metaInfo.getComponent(STACK_NAME_HDP,
        "2.0.8", "HDFS", "HDFS_CLIENT");
    Assert.assertEquals("scripts/hdfs_client_overridden.py",
            component.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