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Turf merge test

HTML

<script src="http://cdn.leafletjs.com/leaflet/v0.7.7/leaflet.js"></script>
<link rel="stylesheet" href="http://cdn.leafletjs.com/leaflet/v0.7.7/leaflet.css">
<script src="https://api.mapbox.com/mapbox.js/plugins/turf/v2.0.2/turf.min.js"></script>
<div id="map"></div>

CSS

#map {
  height: 500px;
}

JavaScript

var map = L.map("map").setView([44.82,-0.59], 14);

L.tileLayer('http://{s}.tile.osm.org/{z}/{x}/{y}.png', {
  attribution: '&copy; <a href="http://osm.org/copyright">OpenStreetMap</a> contributors'
}).addTo(map);

var testJson = {
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "geometry": {
        "type": "Polygon",
        "coordinates":...