Mapshaper infinite loop bug

Penydarren.geojson

simplify.js

var fs = require('fs'),
    mapshaper = require('mapshaper'),
    argv = require('optimist')
      .default('i', 500)
      .argv;
    
if(argv._.length !== 2){
  console.log('Usage: node simplify.js <input.geojson> <output.geojson>');
  process.exit();
}
    
var data = fs.readFileSync(argv._[0]),
    geoJSON = JSON.parse(data);

fs.writeFileSync(argv._[1], JSON.stringify(simplfyGeometry(geoJSON, parseInt(argv.i))));

function simplfyGeometry(origGeom, interval) {
  if(origGeom.type == 'Point') return origGeom;
  
  var mapGeom = mapshaper.createTopology(mapshaper.importGeoJSON(origGeom));
  mapshaper.simplifyPaths(mapGeom.arcs, 'vis');
  mapGeom.arcs.setRetainedInterval(interval);
  mapshaper.findAndRepairIntersections(mapGeom.arcs);
  return mapshaper.exportGeoJSONObject(mapGeom.layers[0], mapGeom.arcs).geometries[0];
}