compile ES6 => ES5 for modules

gistfile1.js

'use strict';

var fs = require('fs');
var path = require('path');
var _ = require('underscore');
var exec = require('child-process-promise').exec;
var Compiler = require('traceur').NodeCompiler;

var traceurOptions = {
  sourceMaps   : 'inline',
  modules      : 'commonjs'
};
var compiler = new Compiler(traceurOptions);

exec('find lib')
  .then(function (result) {
    var files = result.stdout.split("\n");

    var jsFiles = _.filter(files, function (file) {
      var extension = file.substring(file.indexOf('.') + 1);
      return extension === 'js';
    });

    _.each(jsFiles, function (jsFile) {
      fs.readFile(jsFile, function (err, contents) {
        var buildFile = jsFile.replace('lib/', 'build/');
        var compiled = compiler.compile(contents.toString(), buildFile, buildFile);

        exec('mkdir -p ' + path.dirname(buildFile))
          .then(function () {
            fs.writeFile(buildFile, compiled);
          });
      });
    });
  });