Leaflet — wrap GeoJSON around date line (antimeredian)

gistfile1.js

var map = L.map('map').setView([50, 100], 2);

L.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {continuousWorld: false}).addTo(map);

$.getJSON("data/russia-federative-division-0.1.geojson", function (data) {
  L.geoJson(data, {
    coordsToLatLng: function (coords) {
      longitude = coords[0];
      latitude = coords[1];

      var latlng = L.latLng(latitude, longitude);

      if (longitude < 0) {
        return latlng.wrap(360, 0);
      }
      else
        return latlng.wrap();
    }
  }).addTo(map);
});

What is this wrap() function. I am getting error.