lodash/lodash.method/index.js

/**
 * lodash 4.1.0 (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o ./`
 * Copyright 2012-2016 The Dojo Foundation <http://dojofoundation.org/>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright 2009-2016 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 * Available under MIT license <https://lodash.com/license>
 */
var baseSlice = require('lodash._baseslice'),
    get = require('lodash.get'),
    rest = require('lodash.rest'),
    root = require('lodash._root');

/** Used as references for various `Number` constants. */
var INFINITY = 1 / 0;

/** `Object#toString` result references. */
var symbolTag = '[object Symbol]';

/** Used to match property names within property paths. */
var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/,
    reIsPlainProp = /^\w*$/,
    rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]/g;

/** Used to match backslashes in property paths. */
var reEscapeChar = /\\(\\)?/g;

/**
 * A faster alternative to `Function#apply`, this function invokes `func`
 * with the `this` binding of `thisArg` and the arguments of `args`.
 *
 * @private
 * @param {Function} func The function to invoke.
 * @param {*} thisArg The `this` binding of `func`.
 * @param {...*} args The arguments to invoke `func` with.
 * @returns {*} Returns the result of `func`.
 */
function apply(func, thisArg, args) {
  var length = args.length;
  switch (length) {
    case 0: return func.call(thisArg);
    case 1: return func.call(thisArg, args[0]);
    case 2: return func.call(thisArg, args[0], args[1]);
    case 3: return func.call(thisArg, args[0], args[1], args[2]);
  }
  return func.apply(thisArg, args);
}

/** Used for built-in method references. */
var objectProto = Object.prototype;

/**
 * Used to resolve the [`toStringTag`](http://ecma-international.org/ecma-262/6.0/#sec-object.prototype.tostring)
 * of values.
 */
var objectToString = objectProto.toString;

/** Built-in value references. */
var Symbol = root.Symbol;

/** Used to convert symbols to primitives and strings. */
var symbolProto = Symbol ? Symbol.prototype : undefined,
    symbolToString = Symbol ? symbolProto.toString : undefined;

/**
 * The base implementation of `_.invoke` without support for individual
 * method arguments.
 *
 * @private
 * @param {Object} object The object to query.
 * @param {Array|string} path The path of the method to invoke.
 * @param {Array} args The arguments to invoke the method with.
 * @returns {*} Returns the result of the invoked method.
 */
function baseInvoke(object, path, args) {
  if (!isKey(path, object)) {
    path = baseToPath(path);
    object = parent(object, path);
    path = last(path);
  }
  var func = object == null ? object : object[path];
  return func == null ? undefined : apply(func, object, args);
}

/**
 * The base implementation of `_.toPath` which only converts `value` to a
 * path if it's not one.
 *
 * @private
 * @param {*} value The value to process.
 * @returns {Array} Returns the property path array.
 */
function baseToPath(value) {
  return isArray(value) ? value : stringToPath(value);
}

/**
 * Checks if `value` is a property name and not a property path.
 *
 * @private
 * @param {*} value The value to check.
 * @param {Object} [object] The object to query keys on.
 * @returns {boolean} Returns `true` if `value` is a property name, else `false`.
 */
function isKey(value, object) {
  if (typeof value == 'number') {
    return true;
  }
  return !isArray(value) &&
    (reIsPlainProp.test(value) || !reIsDeepProp.test(value) ||
      (object != null && value in Object(object)));
}

/**
 * Gets the parent value at `path` of `object`.
 *
 * @private
 * @param {Object} object The object to query.
 * @param {Array} path The path to get the parent value of.
 * @returns {*} Returns the parent value.
 */
function parent(object, path) {
  return path.length == 1 ? object : get(object, baseSlice(path, 0, -1));
}

/**
 * Converts `string` to a property path array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the property path array.
 */
function stringToPath(string) {
  var result = [];
  toString(string).replace(rePropName, function(match, number, quote, string) {
    result.push(quote ? string.replace(reEscapeChar, '$1') : (number || match));
  });
  return result;
}

/**
 * Gets the last element of `array`.
 *
 * @static
 * @memberOf _
 * @category Array
 * @param {Array} array The array to query.
 * @returns {*} Returns the last element of `array`.
 * @example
 *
 * _.last([1, 2, 3]);
 * // => 3
 */
function last(array) {
  var length = array ? array.length : 0;
  return length ? array[length - 1] : undefined;
}

/**
 * Checks if `value` is classified as an `Array` object.
 *
 * @static
 * @memberOf _
 * @type Function
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
 * @example
 *
 * _.isArray([1, 2, 3]);
 * // => true
 *
 * _.isArray(document.body.children);
 * // => false
 *
 * _.isArray('abc');
 * // => false
 *
 * _.isArray(_.noop);
 * // => false
 */
var isArray = Array.isArray;

/**
 * Checks if `value` is object-like. A value is object-like if it's not `null`
 * and has a `typeof` result of "object".
 *
 * @static
 * @memberOf _
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
 * @example
 *
 * _.isObjectLike({});
 * // => true
 *
 * _.isObjectLike([1, 2, 3]);
 * // => true
 *
 * _.isObjectLike(_.noop);
 * // => false
 *
 * _.isObjectLike(null);
 * // => false
 */
function isObjectLike(value) {
  return !!value && typeof value == 'object';
}

/**
 * Checks if `value` is classified as a `Symbol` primitive or object.
 *
 * @static
 * @memberOf _
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
 * @example
 *
 * _.isSymbol(Symbol.iterator);
 * // => true
 *
 * _.isSymbol('abc');
 * // => false
 */
function isSymbol(value) {
  return typeof value == 'symbol' ||
    (isObjectLike(value) && objectToString.call(value) == symbolTag);
}

/**
 * Converts `value` to a string if it's not one. An empty string is returned
 * for `null` and `undefined` values. The sign of `-0` is preserved.
 *
 * @static
 * @memberOf _
 * @category Lang
 * @param {*} value The value to process.
 * @returns {string} Returns the string.
 * @example
 *
 * _.toString(null);
 * // => ''
 *
 * _.toString(-0);
 * // => '-0'
 *
 * _.toString([1, 2, 3]);
 * // => '1,2,3'
 */
function toString(value) {
  // Exit early for strings to avoid a performance hit in some environments.
  if (typeof value == 'string') {
    return value;
  }
  if (value == null) {
    return '';
  }
  if (isSymbol(value)) {
    return Symbol ? symbolToString.call(value) : '';
  }
  var result = (value + '');
  return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
}

/**
 * Creates a function that invokes the method at `path` of a given object.
 * Any additional arguments are provided to the invoked method.
 *
 * @static
 * @memberOf _
 * @category Util
 * @param {Array|string} path The path of the method to invoke.
 * @param {...*} [args] The arguments to invoke the method with.
 * @returns {Function} Returns the new function.
 * @example
 *
 * var objects = [
 *   { 'a': { 'b': { 'c': _.constant(2) } } },
 *   { 'a': { 'b': { 'c': _.constant(1) } } }
 * ];
 *
 * _.map(objects, _.method('a.b.c'));
 * // => [2, 1]
 *
 * _.invokeMap(_.sortBy(objects, _.method(['a', 'b', 'c'])), 'a.b.c');
 * // => [1, 2]
 */
var method = rest(function(path, args) {
  return function(object) {
    return baseInvoke(object, path, args);
  };
});

module.exports = method;