gistfile1.js

app.commands.file = function file (filename, cb) {
  this.log.info('Attempting to open "' + filename +'"');
  var newFile = getNewFile( filename ,cb);
  app.log.info("Changes are comming!:\n"+newFile);
  cb(null);
};

var getNewFile = function(filename, cb){
  fs.readFile(filename, function (err, data) {
    if (err) cb( err);
    //app.log.info(data);
   // app.log.info("Regex");
    var re = /require\s*\(\s*['"]sys['"]\s*\)/g;
    var reFull = /sys\s*=\s*require\s*\(\s*['"]sys['"]\s*\)/g;
    var rePart = /sys\./g;
    var replacement = "require('util')";
    var replacementFull = "util = require('util')";
    var replacementPart = 'util.';
    var dataMod = '';
    if (XRegExp.test(data, re)){
      if (XRegExp.test(data, reFull)){
        dataMod = XRegExp.replace(XRegExp.replace(data, rePart , replacementPart , 'all' ), reFull , replacementFull , 'all' );
      }else{
        dataMod = XRegExp.replace(data, re , replacement , 'all' );
      }
      //do stuff to dataMod
      //app.log.info(dataMod);
      return dataMod;
    }else{
      //app.log.info('No '+'require(\'sys\')'.magenta.bold+' text found in file');
      return null;
    }

  });
};