doReturn(amNodeMap).when(appContext).getAllNodes();
doReturn(DAGAppMasterState.RUNNING).when(appContext).getAMState();
doReturn(dagID).when(appContext).getCurrentDAGID();
doReturn(mock(ClusterInfo.class)).when(appContext).getClusterInfo();
TaskSchedulerEventHandler taskSchedulerEventHandlerReal = new TaskSchedulerEventHandlerForTest(appContext, eventHandler, rmClient, new AlwaysMatchesContainerMatcher());
TaskSchedulerEventHandler taskSchedulerEventHandler = spy(taskSchedulerEventHandlerReal);
taskSchedulerEventHandler.init(tezConf);
taskSchedulerEventHandler.start();
TaskSchedulerWithDrainableAppCallback taskScheduler = (TaskSchedulerWithDrainableAppCallback) ((TaskSchedulerEventHandlerForTest) taskSchedulerEventHandler)