lodash/lodash.mixin/index.js

/**
 * lodash 3.0.4 (Custom Build) <https://lodash.com/>
 * Build: `lodash modern modularize exports="npm" -o ./`
 * Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 * Available under MIT license <https://lodash.com/license>
 */
var arrayCopy = require('lodash._arraycopy'),
    baseFunctions = require('lodash._basefunctions'),
    isFunction = require('lodash.isfunction'),
    keys = require('lodash.keys');

/**
 * Appends the elements of `values` to `array`.
 *
 * @private
 * @param {Array} array The array to modify.
 * @param {Array} values The values to append.
 * @returns {Array} Returns `array`.
 */
function arrayPush(array, values) {
  var index = -1,
      length = values.length,
      offset = array.length;

  while (++index < length) {
    array[offset + index] = values[index];
  }
  return array;
}

/**
 * Checks if `value` is the [language type](https://es5.github.io/#x8) of `Object`.
 * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
 *
 * @static
 * @memberOf _
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is an object, else `false`.
 * @example
 *
 * _.isObject({});
 * // => true
 *
 * _.isObject([1, 2, 3]);
 * // => true
 *
 * _.isObject(1);
 * // => false
 */
function isObject(value) {
  // Avoid a V8 JIT bug in Chrome 19-20.
  // See https://code.google.com/p/v8/issues/detail?id=2291 for more details.
  var type = typeof value;
  return !!value && (type == 'object' || type == 'function');
}

/**
 * Adds all own enumerable function properties of a source object to the
 * destination object. If `object` is a function then methods are added to
 * its prototype as well.
 *
 * **Note:** Use `_.runInContext` to create a pristine `lodash` function to
 * avoid conflicts caused by modifying the original.
 *
 * @static
 * @memberOf _
 * @category Utility
 * @param {Function|Object} [object=lodash] The destination object.
 * @param {Object} source The object of functions to add.
 * @param {Object} [options] The options object.
 * @param {boolean} [options.chain=true] Specify whether the functions added
 *  are chainable.
 * @returns {Function|Object} Returns `object`.
 * @example
 *
 * function vowels(string) {
 *   return _.filter(string, function(v) {
 *     return /[aeiou]/i.test(v);
 *   });
 * }
 *
 * _.mixin({ 'vowels': vowels });
 * _.vowels('fred');
 * // => ['e']
 *
 * _('fred').vowels().value();
 * // => ['e']
 *
 * _.mixin({ 'vowels': vowels }, { 'chain': false });
 * _('fred').vowels();
 * // => ['e']
 */
function mixin(object, source, options) {
  var methodNames = baseFunctions(source, keys(source));

  var chain = true,
      index = -1,
      isFunc = isFunction(object),
      length = methodNames.length;

  if (options === false) {
    chain = false;
  } else if (isObject(options) && 'chain' in options) {
    chain = options.chain;
  }
  while (++index < length) {
    var methodName = methodNames[index],
        func = source[methodName];

    object[methodName] = func;
    if (isFunc) {
      object.prototype[methodName] = (function(func) {
        return function() {
          var chainAll = this.__chain__;
          if (chain || chainAll) {
            var result = object(this.__wrapped__),
                actions = result.__actions__ = arrayCopy(this.__actions__);

            actions.push({ 'func': func, 'args': arguments, 'thisArg': object });
            result.__chain__ = chainAll;
            return result;
          }
          return func.apply(object, arrayPush([this.value()], arguments));
        };
      }(func));
    }
  }
  return object;
}

module.exports = mixin;