### Question:
RollingUpdateOpFactory { public RollingUpdateOp yield() { return new RollingUpdateOp(ImmutableList.<ZooKeeperOperation>of(), ImmutableList.<Map<String, Object>>of()); } RollingUpdateOpFactory(final DeploymentGroupTasks tasks,
                                final DeploymentGroupEventFactory eventFactory); RollingUpdateOp start(final DeploymentGroup deploymentGroup,
                               final ZooKeeperClient client); RollingUpdateOp nextTask(); RollingUpdateOp nextTask(final List<ZooKeeperOperation> operations); RollingUpdateOp yield(); RollingUpdateOp error(final String msg, final String host,
                               final RollingUpdateError errorCode,
                               final Map<String, Object> metadata); RollingUpdateOp error(final String msg, final String host,
                               final RollingUpdateError errorCode); RollingUpdateOp error(final Exception ex, final String host,
                               final RollingUpdateError errorCode);  }### Answer:
@Test public void testYield() { final DeploymentGroupTasks deploymentGroupTasks = DeploymentGroupTasks.newBuilder() .setTaskIndex(0) .setRolloutTasks(Lists.newArrayList( RolloutTask.of(RolloutTask.Action.UNDEPLOY_OLD_JOBS, "host1"), RolloutTask.of(RolloutTask.Action.AWAIT_RUNNING, "host1"), RolloutTask.of(RolloutTask.Action.DEPLOY_NEW_JOB, "host1"))) .setDeploymentGroup(MANUAL_DEPLOYMENT_GROUP) .build(); final RollingUpdateOpFactory opFactory = new RollingUpdateOpFactory( deploymentGroupTasks, eventFactory); final RollingUpdateOp op = opFactory.yield(); assertEquals(0, op.operations().size()); assertEquals(0, op.events().size()); }