Function getOptions

src/utils/event-hub.ts:17–40

()

const eventMap = new WeakMap<Scrollbar, EventConfig[]>();

function getOptions(): typeof eventListenerOptions {
  if (eventListenerOptions !== undefined) {
    return eventListenerOptions;
  }

  let supportPassiveEvent = false;

  try {
    const noop = () => {};
    const options = Object.defineProperty({}, 'passive', {
      enumerable: true,
      get() {
        supportPassiveEvent = true;
        return true;
      },
    });
    window.addEventListener('testPassive', noop, options);
    window.removeEventListener('testPassive', noop, options);
  } catch (e) {}

  eventListenerOptions = supportPassiveEvent ? { passive: false } as EventListenerOptions : false;

  return eventListenerOptions;
}

export function eventScope(scrollbar: Scrollbar) {
  const configs = eventMap.get(scrollbar) || [];