Be Concise II - I Need Squares.js

/*
Description:
Be Concise II - I Need Squares
You are given a program squaresOnly that accepts an array of natural numbers up to and including
100
(and including 0) of length >= 1, array, and returns a new array containing only square numbers that have appeared in the input array.

Refactor the solution to use as few characters as possible. There is a maximum character limit of 127. Here are a few hints:

There are a lot of handy built-in Array methods in Javascript that you may have never heard of even after completing a basic course in Javascript (e.g. those provided by Codecademy) - well, at least I haven't heard of until quite recently. You may also want to research any new built-in methods offered by ES6, the newest specification of Javascript at the time of writing.
Don't you think the array parameter is a bit wordy? ;)
Good luck! :D
*/

function squaresOnly(array) {
return array.filter(num=>Number.isInteger(Math.sqrt(num)))}