focusin.js

/* from https://gist.github.com/nuxodin/9250e56a3ce6c0446efa */

function polyfill () {
  var w = window
  var d = w.document

  if (w.onfocusin === undefined) {
    d.addEventListener('focus', addPolyfill, true)
    d.addEventListener('blur', addPolyfill, true)
    d.addEventListener('focusin', removePolyfill, true)
    d.addEventListener('focusout', removePolyfill, true)
  }

  function addPolyfill (e) {
    var type = e.type === 'focus' ? 'focusin' : 'focusout'
    var event = new window.CustomEvent(type, { bubbles: true, cancelable: false })
    event.c1Generated = true
    e.target.dispatchEvent(event)
  }

  function removePolyfill (e) {
    if (!e.c1Generated) {
      d.removeEventListener('focus', addPolyfill, true)
      d.removeEventListener('blur', addPolyfill, true)
      d.removeEventListener('focusin', removePolyfill, true)
      d.removeEventListener('focusout', removePolyfill, true)
    }
    setTimeout(function () {
      d.removeEventListener('focusin', removePolyfill, true)
      d.removeEventListener('focusout', removePolyfill, true)
    })
  }
}

module.exports = {
  polyfill: polyfill
}