odin-javascript-exercises/node_modules/lodash/_baseUniq.js

73 lines
1.9 KiB
JavaScript
Raw Normal View History

2017-12-15 10:56:14 -08:00
var SetCache = require('./_SetCache'),
arrayIncludes = require('./_arrayIncludes'),
arrayIncludesWith = require('./_arrayIncludesWith'),
cacheHas = require('./_cacheHas'),
createSet = require('./_createSet'),
setToArray = require('./_setToArray');
/** Used as the size to enable large array optimizations. */
var LARGE_ARRAY_SIZE = 200;
/**
* The base implementation of `_.uniqBy` without support for iteratee shorthands.
*
* @private
* @param {Array} array The array to inspect.
* @param {Function} [iteratee] The iteratee invoked per element.
* @param {Function} [comparator] The comparator invoked per element.
* @returns {Array} Returns the new duplicate free array.
*/
function baseUniq(array, iteratee, comparator) {
var index = -1,
includes = arrayIncludes,
length = array.length,
isCommon = true,
result = [],
seen = result;
if (comparator) {
isCommon = false;
includes = arrayIncludesWith;
}
else if (length >= LARGE_ARRAY_SIZE) {
var set = iteratee ? null : createSet(array);
if (set) {
return setToArray(set);
}
isCommon = false;
includes = cacheHas;
seen = new SetCache;
}
else {
seen = iteratee ? [] : result;
}
outer:
while (++index < length) {
var value = array[index],
computed = iteratee ? iteratee(value) : value;
value = (comparator || value !== 0) ? value : 0;
if (isCommon && computed === computed) {
var seenIndex = seen.length;
while (seenIndex--) {
if (seen[seenIndex] === computed) {
continue outer;
}
}
if (iteratee) {
seen.push(computed);
}
result.push(value);
}
else if (!includes(seen, computed, comparator)) {
if (seen !== result) {
seen.push(computed);
}
result.push(value);
}
}
return result;
}
module.exports = baseUniq;