Function unstable_scheduleCallback

dash/deps/react@18.2.0.js:2752–2833

(priorityLevel, callback, options)

  }

  function unstable_scheduleCallback(priorityLevel, callback, options) {
    var currentTime = getCurrentTime();
    var startTime;

    if (typeof options === 'object' && options !== null) {
      var delay = options.delay;

      if (typeof delay === 'number' && delay > 0) {
        startTime = currentTime + delay;
      } else {
        startTime = currentTime;
      }
    } else {
      startTime = currentTime;
    }

    var timeout;

    switch (priorityLevel) {
      case ImmediatePriority:
        timeout = IMMEDIATE_PRIORITY_TIMEOUT;
        break;

      case UserBlockingPriority:
        timeout = USER_BLOCKING_PRIORITY_TIMEOUT;
        break;

      case IdlePriority:
        timeout = IDLE_PRIORITY_TIMEOUT;
        break;

      case LowPriority:
        timeout = LOW_PRIORITY_TIMEOUT;
        break;

      case NormalPriority:
      default:
        timeout = NORMAL_PRIORITY_TIMEOUT;
        break;
    }

    var expirationTime = startTime + timeout;
    var newTask = {
      id: taskIdCounter++,
      callback: callback,
      priorityLevel: priorityLevel,
      startTime: startTime,
      expirationTime: expirationTime,
      sortIndex: -1
    };

    if (startTime > currentTime) {
      // This is a delayed task.
      newTask.sortIndex = startTime;
      push(timerQueue, newTask);

      if (peek(taskQueue) === null && newTask === peek(timerQueue)) {
        // All tasks are delayed, and this is the task with the earliest delay.