如何在leaflet.draw中将形状限制为简单多边形？

Question

我正在使用leaflet.draw在地图上绘制多边形。即使在polygon的选项中，我设置了

allowIntersection: false, // Restricts shapes to simple polygons

我仍然可以绘制自相交的多边形（如演示中所示）。如何解决？

// center of the map
var center = [-33.8650, 151.2094];

// Create the map
var map = L.map('map').setView(center, 6);

// Set up the OSM layer
L.tileLayer(
  'https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    attribution: 'Data © <a href="http://osm.org/copyright">OpenStreetMap</a>',
    maxZoom: 18
  }).addTo(map);

// add a marker in the given location
L.marker(center).addTo(map);

// Initialise the FeatureGroup to store editable layers
var editableLayers = new L.FeatureGroup();
map.addLayer(editableLayers);

var drawPluginOptions = {
  position: 'topleft',
  draw: {
    polygon: {
      allowIntersection: false, // Restricts shapes to simple polygons
      drawError: {
        color: '#e1e100', // Color the shape will turn when intersects
        message: '<strong>Oh snap!<strong> you can\'t draw that!' // Message that will show when intersect
      },
      shapeOptions: {
        color: '#97009c'
      }
    },
    // disable toolbar item by setting it to false
    polyline: false,
    circle: false, // Turns off this drawing tool
    rectangle: false,
    marker: false,
  },
  edit: {
    featureGroup: editableLayers, //REQUIRED!!
    remove: false
  }
};

// Initialise the draw control and pass it the FeatureGroup of editable layers
var drawControl = new L.Control.Draw(drawPluginOptions);
map.addControl(drawControl);

var editableLayers = new L.FeatureGroup();
map.addLayer(editableLayers);

map.on('draw:created', function(e) {
  var type = e.layerType,
    layer = e.layer;

  if (type === 'marker') {
    layer.bindPopup('A popup!');
  }

  editableLayers.addLayer(layer);
});

html,
body {
  height: 100%;
}
#map {
  height: 100%;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.0.0-beta.2.rc.2/leaflet.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.0.0-beta.2.rc.2/leaflet.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet.draw/0.2.3/leaflet.draw.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/leaflet.draw/0.2.3/leaflet.draw.css" rel="stylesheet" />
<div id="map"></div>