Mapbox gl geocoder flyTo

HTML

<script src="	https://npmcdn.com/@turf/turf/turf.min.js"></script>
<script src="https://api.tiles.mapbox.com/mapbox-gl-js/v0.38.0/mapbox-gl.js"></script>
<link rel="stylesheet" href="https://api.tiles.mapbox.com/mapbox-gl-js/v0.38.0/mapbox-gl.css">
<link rel="stylesheet" href="https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-geocoder/v2.1.0/mapbox-gl-geocoder.css">
<script src="https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-geocoder/v2.1.0/mapbox-gl-geocoder.min.js"></script>
<div id="map"></div>

CSS

#map {
  height: 500px;
  display: none;
  }

JavaScript

var token = 'pk.eyJ1IjoiZmFyYWRheTIiLCJhIjoiTUVHbDl5OCJ9.buFaqIdaIM3iXr1BOYKpsQ';
mapboxgl.accessToken = token;
var map = new mapboxgl.Map({
    container: 'map', // container id
    style: 'mapbox://styles/mapbox/streets-v9', //stylesheet location
    center: [-74.50, 40], // starting position
    zoom: 9 // starting zoom
});

var geocoderIsFlying;

var geocoder = new MapboxGeocoder({accessToken: token});
	geocoder.on('result', function(ev) {
  console.log("CENTER:", ev.result.center);
  console.log("BOUNDS:", map.getBounds());
  
  geocoderIsFlying = true;
  map.once('moveend', moveHandler);
});

map.addControl(geocoder);

function moveHandler(e) {
	if(geocoderIsFlying === true) {
    geocoderIsFlying = false;
    console.log(geocoderIsFlying);
  }	
}