Files
lodash/lodash.intersection/index.js
John-David Dalton 0847978784 Bump to v3.2.0.
2018-02-03 19:13:28 -08:00

121 lines
3.6 KiB
JavaScript

/**
* lodash 3.2.0 (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 baseIndexOf = require('lodash._baseindexof'),
cacheIndexOf = require('lodash._cacheindexof'),
createCache = require('lodash._createcache'),
restParam = require('lodash.restparam');
/**
* Used as the [maximum length](http://ecma-international.org/ecma-262/6.0/#sec-number.max_safe_integer)
* of an array-like value.
*/
var MAX_SAFE_INTEGER = 9007199254740991;
/**
* The base implementation of `_.property` without support for deep paths.
*
* @private
* @param {string} key The key of the property to get.
* @returns {Function} Returns the new function.
*/
function baseProperty(key) {
return function(object) {
return object == null ? undefined : object[key];
};
}
/**
* Gets the "length" property value of `object`.
*
* **Note:** This function is used to avoid a [JIT bug](https://bugs.webkit.org/show_bug.cgi?id=142792)
* that affects Safari on at least iOS 8.1-8.3 ARM64.
*
* @private
* @param {Object} object The object to query.
* @returns {*} Returns the "length" value.
*/
var getLength = baseProperty('length');
/**
* Checks if `value` is array-like.
*
* @private
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is array-like, else `false`.
*/
function isArrayLike(value) {
return value != null && isLength(getLength(value));
}
/**
* Checks if `value` is a valid array-like length.
*
* **Note:** This function is based on [`ToLength`](http://ecma-international.org/ecma-262/6.0/#sec-tolength).
*
* @private
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
*/
function isLength(value) {
return typeof value == 'number' && value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
}
/**
* Creates an array of unique values that are included in all of the provided
* arrays using [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero)
* for equality comparisons.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to inspect.
* @returns {Array} Returns the new array of shared values.
* @example
* _.intersection([1, 2], [4, 2], [2, 1]);
* // => [2]
*/
var intersection = restParam(function(arrays) {
var othLength = arrays.length,
othIndex = othLength,
caches = Array(length),
indexOf = baseIndexOf,
isCommon = true,
result = [];
while (othIndex--) {
var value = arrays[othIndex] = isArrayLike(value = arrays[othIndex]) ? value : [];
caches[othIndex] = (isCommon && value.length >= 120) ? createCache(othIndex && value) : null;
}
var array = arrays[0],
index = -1,
length = array ? array.length : 0,
seen = caches[0];
outer:
while (++index < length) {
value = array[index];
if ((seen ? cacheIndexOf(seen, value) : indexOf(result, value, 0)) < 0) {
var othIndex = othLength;
while (--othIndex) {
var cache = caches[othIndex];
if ((cache ? cacheIndexOf(cache, value) : indexOf(arrays[othIndex], value, 0)) < 0) {
continue outer;
}
}
if (seen) {
seen.push(value);
}
result.push(value);
}
}
return result;
});
module.exports = intersection;