simulate-event.js
function getOverrides (eventType, options) {
  if (eventType === 'KeyboardEvent' && options) {
    return {
      keyCode: options.keyCode || 0,
      key: options.key || 0,
      which: options.which || options.keyCode || 0
    }
  }
}
function getOverrides (eventType, options) {
  if (eventType === 'KeyboardEvent' && options) {
    return {
      keyCode: options.keyCode || 0,
      key: options.key || 0,
      which: options.which || options.keyCode || 0
    }
  }
}
function getOverrides ( eventType , options ) { if ( eventType === 'KeyboardEvent' && options ) { return { keyCode : options . keyCode || 0 , key : options . key || 0 , which : options . which || options . keyCode || 0 } } }
Get attributes which must be overriden manually.

@param {String} eventType
@param {Object} options.
Get attributes which must be overriden manually .