@Test
  public void testDestroyIndexOnRegionIsIdempotent() throws Exception {
    createSimpleIndexA();

    CommandStringBuilder csb = new CommandStringBuilder(CliStrings.DESTROY_INDEX);
    csb.addOption(CliStrings.DESTROY_INDEX__REGION, regionName);
    csb.addOption(CliStrings.IFEXISTS, "true");
    gfsh.executeAndAssertThat(csb.toString()).statusIsSuccess()
        .containsOutput("Destroyed all indexes on region regionA");
    gfsh.executeAndAssertThat(csb.toString()).statusIsSuccess()
        .containsOutput("Destroyed all indexes on region regionA");
  }
this test class test: CreateIndexCommand, DestroyIndexCommand, ListIndexCommand
geode-dunit/src/main/java/org/apache/geode/management/internal/cli/commands/IndexCommandsIntegrationTestBase.java