code: function accept_file(filename, state) {
  	state = state || {};
  	debug.assert(filename).is('string');
  	debug.assert(state).is('object');
  	if(!state.file) { return; }
  	var ext = PATH.extname(filename);
  	return (ext === '.js') ? true : false;
  }
docs: Returns true if file should be ignored