text: (function () {
    function install (Vue) {
      var setWechatTitle = function (title, img) {
        if (title === undefined || window.document.title === title) {
          return
        }
        document.title = title
        var mobile = navigator.userAgent.toLowerCase()
        if (/iphone|ipad|ipod/.test(mobile)) {
          var iframe = document.createElement('iframe')
          iframe.style.display = 'none'
          // 替换成站标favicon路径或者任意存在的较小的图片即可，支付宝小程序引用原先base64会有安全警告
          img && iframe.setAttribute('src', img)
          var iframeCallback = function () {
            setTimeout(function () {
              iframe.removeEventListener('load', iframeCallback)
              document.body.removeChild(iframe)
            }, 0)
          }
          iframe.addEventListener('load', iframeCallback)
          document.body.appendChild(iframe)
        }
      }
      Vue.directive('wechat-title', function (el, binding) {
        setWechatTitle(binding.value, el.getAttribute('img-set') || null)
      })
    }
  
    if (typeof exports === 'object') {
      module.exports = install
    } else if (typeof define === 'function' && define.amd) {
      define([], function () {
        return install
      })
    } else if (window.Vue) {
      Vue.use(install)
    }
  })()
  