code: function(editorFile, fileName, callback) {
  			if (isURL(fileName)) {
  				return callback(fileName);
  			}
  
  			var dirname = editorFile
  			var filepath;
  			fileName = fileName.replace(/^\/+/, '');
  			while (dirname && dirname !== path.dirname(dirname)) {
  				dirname = path.dirname(dirname);
  				filepath = path.join(dirname, fileName);
  				if (fs.existsSync(filepath))
  					return callback(filepath);
  			}
  
  			callback(null);
  		}
docs: Locate <code>file_name</code> file that relates to <code>editor_file</code>.
  File name may be absolute or relative path
  
  <b>Dealing with absolute path.</b>
  Many modern editors have a "project" support as information unit, but you
  should not rely on project path to find file with absolute path. First,
  it requires user to create a project before using this method (and this
  is not very convenient). Second, project path doesn't always points to
  to website's document root folder: it may point, for example, to an
  upper folder which contains server-side scripts.
  
  For better result, you should use the following algorithm in locating
  absolute resources:
  1) Get parent folder for <code>editorFile</code> as a start point
  2) Append required <code>fileName</code> to start point and test if
  file exists
  3) If it doesn't exists, move start point one level up (to parent folder)
  and repeat step 2.
  
  @param {String} editorFile
  @param {String} fileName
  @return {String} Returns null if <code>fileName</code> cannot be located