turf-buffer/test/test.js

turf buffer module

var test = require('tape');
var buffer = require('../');
var fs = require('fs');
var glob = require('glob');
var featurecollection = require('turf-featurecollection');
var extent = require('turf-extent');
var point = require('turf-point');
var distance = require('turf-distance');
var normalize = require('geojson-normalize');

test('buffer', function(t){
  var fixtures = glob.sync(__dirname+'/fixtures/in/*.geojson');
  fixtures.forEach(function(path){
    var fixture = JSON.parse(fs.readFileSync(path));
    var bbox = extent(fixture);
    var width = distance(
      point(bbox.slice(0,2)),
      point(bbox.slice(2,5)),
      'miles'
      );
    if(!width) width = 1;
    var buffed = buffer(fixture, width * 0.1, 'miles');

    t.ok(buffed, fixture.type);
    if(fixture.type === 'Feature') {
      if(fixture.geometry.type === 'Point') t.equals(buffed.geometry.type, 'Polygon');
      if(fixture.geometry.type === 'LineString') t.equals(buffed.geometry.type, 'Polygon');
      if(fixture.geometry.type === 'Polygon') t.equals(buffed.geometry.type, 'Polygon');
      if(fixture.geometry.type === 'MultiPoint') t.equals(buffed.geometry.type, 'MultiPolygon');
      if(fixture.geometry.type === 'MultiLineString') t.equals(buffed.geometry.type, 'MultiPolygon');
      if(fixture.geometry.type === 'MultiPolygon') t.equals(buffed.geometry.type, 'MultiPolygon');
      if(fixture.geometry.type === 'GeometryCollection') t.equals(buffed.geometry.type, 'MultiPolygon');
    } else t.equals(buffed.type, 'FeatureCollection');

    buffed = normalize(buffed);
    buffed.features = buffed.features.map(function(f) {
      f.properties = {
        'fill': '#000',
        'fill-opacity': 0.3,
        'stroke': '#0ff'
      };
      return f;
    });
 
    buffed.features = buffed.features.concat(normalize(fixture).features);
    fs.writeFileSync(
        __dirname+'/fixtures/out/'+path.split('/')[path.split('/').length-1],
        JSON.stringify(buffed)
      );
  });
  t.end();
});