check passive events

一、作用

二、支持被动浏览器事件

备注

• canUseDOM() 由 ExecutionEnvironment#canUseDOM 实现

export let passiveBrowserEventsSupported: boolean = false;

// Check if browser support events with passive listeners
// 检查浏览器是否支持带有被动监听器的事件
// https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#Safely_detecting_option_support
if (canUseDOM) {
  try {
    const options: {
      passive?: void;
    } = {};

    Object.defineProperty(options, 'passive', {
      get: function () {
        passiveBrowserEventsSupported = true;
      },
    });
    window.addEventListener('test', options, options);
    window.removeEventListener('test', options, options);
  } catch (e) {
    passiveBrowserEventsSupported = false;
  }
}