prodio-mongo-store/lib/utils.js

A MongoDB adapter for prodio-stores

var extend = function() {
  // copy reference to target object
  var target = arguments[0] || {}, i = 1, length = arguments.length, deep = false, options, name, src, copy;

  // Handle a deep copy situation
  if (typeof target === 'boolean') {
    deep = target;
    target = arguments[1] || {};
    // skip the boolean and the target
    i = 2;
  }

  // Handle case when target is a string or something (possible in deep copy)
  if (typeof target !== 'object' && !typeof target === 'function')
    target = {};

  var isPlainObject = function(obj) {
    // Must be an Object.
    // Because of IE, we also have to check the presence of the constructor property.
    // Make sure that DOM nodes and window objects don't pass through, as well
    if (!obj || toString.call(obj) !== '[object Object]' || obj.nodeType || obj.setInterval)
      return false;

    var has_own_constructor = hasOwnProperty.call(obj, 'constructor');
    var has_is_property_of_method = obj.constructor&&hasOwnProperty.call(obj.constructor.prototype, 'isPrototypeOf');
    // Not own constructor property must be Object
    if (obj.constructor && !has_own_constructor && !has_is_property_of_method)
      return false;

    // Own properties are enumerated firstly, so to speed up,
    // if last one is own, then all properties are own.

    var last_key;
    for (key in obj)
      last_key = key;

    return typeof last_key === 'undefined' || hasOwnProperty.call(obj, last_key);
  };

  for (; i < length; i++) {
    // Only deal with non-null/undefined values
    if ((options = arguments[i]) !== null) {
      // Extend the base object
      for (name in options) {
        src = target[name];
        copy = options[name];

        // Prevent never-ending loop
        if (target === copy)
            continue;

        // Recurse if we're merging object literal values or arrays
        if (deep && copy && (isPlainObject(copy) || Array.isArray(copy))) {
          var clone = src && (isPlainObject(src) || Array.isArray(src)) ? src : Array.isArray(copy) ? [] : {};

          // Never move original objects, clone them
          target[name] = extend(deep, clone, copy);

        // Don't bring in undefined values
        } else if (typeof copy !== 'undefined')
          target[name] = copy;
      }
    }
  }

  // Return the modified object
  return target;
};

module.exports = {
  extend: function(){
    if(!arguments.length) return {};
    var args = Array.apply(null, arguments);
    if(typeof(args[0]) === 'boolean'){
      var deep = args.shift();
      args.unshift(deep, {});
    }else args.unshift(true, {});
    return extend.apply(null, args);
  }
};