private List<TaskModel> generateSampleTasks(int count) {
        if (count == 0) {
            return null;
        }
        List<TaskModel> tasks = new ArrayList<>();
        for (int i = 0; i < count; i++) {
            TaskModel task = new TaskModel();
            task.setTaskId(UUID.randomUUID().toString());
            task.setSeq(i);
            task.setRetryCount(1);
            task.setTaskType("task" + (i + 1));
            task.setStatus(TaskModel.Status.COMPLETED);
            task.setTaskDefName("taskX");
            task.setReferenceTaskName("task_ref" + (i + 1));
            tasks.add(task);
        }

        return tasks;
    }
Simulate Queue push failures and assert that scheduleTask doesn't throw an exception.
core/src/test/java/com/netflix/conductor/core/execution/TestWorkflowExecutor.java