lib/parse.js
function clone(obj) {
  var key;
  var copy = {};
  for (key in obj) {
    /* istanbul ignore else */
    if (hop.call(obj, key)) {
      copy[key] = obj[key];
    }
  }
  return copy;
}
function clone(obj) {
  var key;
  var copy = {};
  for (key in obj) {
    /* istanbul ignore else */
    if (hop.call(obj, key)) {
      copy[key] = obj[key];
    }
  }
  return copy;
}
function clone ( obj ) { var key ; var copy = { } ; for ( key in obj ) { /* istanbul ignore else */ if ( hop . call ( obj , key ) ) { copy [ key ] = obj [ key ] ; } } return copy ; }
Shallow-clone an object.
Shallow - clone an object .