You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

75 lines
2.2 KiB

var SetCache = require('./_SetCache'),
arrayIncludes = require('./_arrayIncludes'),
arrayIncludesWith = require('./_arrayIncludesWith'),
arrayMap = require('./_arrayMap'),
baseUnary = require('./_baseUnary'),
cacheHas = require('./_cacheHas');
/* Built-in method references for those with the same name as other `lodash` methods. */
var nativeMin = Math.min;
/**
* The base implementation of methods like `_.intersection`, without support
* for iteratee shorthands, that accepts an array of arrays to inspect.
*
* @private
* @param {Array} arrays The arrays to inspect.
* @param {Function} [iteratee] The iteratee invoked per element.
* @param {Function} [comparator] The comparator invoked per element.
* @returns {Array} Returns the new array of shared values.
*/
function baseIntersection(arrays, iteratee, comparator) {
var includes = comparator ? arrayIncludesWith : arrayIncludes,
length = arrays[0].length,
othLength = arrays.length,
othIndex = othLength,
caches = Array(othLength),
maxLength = Infinity,
result = [];
while (othIndex--) {
var array = arrays[othIndex];
if (othIndex && iteratee) {
array = arrayMap(array, baseUnary(iteratee));
}
maxLength = nativeMin(array.length, maxLength);
caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120))
? new SetCache(othIndex && array)
: undefined;
}
array = arrays[0];
var index = -1,
seen = caches[0];
outer:
while (++index < length && result.length < maxLength) {
var value = array[index],
computed = iteratee ? iteratee(value) : value;
value = (comparator || value !== 0) ? value : 0;
if (!(seen
? cacheHas(seen, computed)
: includes(result, computed, comparator)
)) {
othIndex = othLength;
while (--othIndex) {
var cache = caches[othIndex];
if (!(cache
? cacheHas(cache, computed)
: includes(arrays[othIndex], computed, comparator))
) {
continue outer;
}
}
if (seen) {
seen.push(computed);
}
result.push(value);
}
}
return result;
}
module.exports = baseIntersection;