jsondiffpatch/src/clone.js

Diff & Patch for Javascript objects

var isArray = (typeof Array.isArray === 'function') ?
  // use native function
  Array.isArray :
  // use instanceof operator
  function(a) {
    return a instanceof Array;
  };

function cloneRegExp(re) {
  var regexMatch = /^\/(.*)\/([gimyu]*)$/.exec(re.toString());
  return new RegExp(regexMatch[1], regexMatch[2]);
}

function clone(arg) {
  if (typeof arg !== 'object') {
    return arg;
  }
  if (arg === null) {
    return null;
  }
  if (isArray(arg)) {
    return arg.map(clone);
  }
  if (arg instanceof Date) {
    return new Date(arg.getTime());
  }
  if (arg instanceof RegExp) {
    return cloneRegExp(arg);
  }
  var cloned = {};
  for (var name in arg) {
    if (Object.prototype.hasOwnProperty.call(arg, name)) {
      cloned[name] = clone(arg[name]);
    }
  }
  return cloned;
}

module.exports = clone;