Perf test on various methods to extract unique elements out of an array of objects

uniques.js

const f = require('faker');

let dup = (a) => a.map((el) => Object.assign({}, el));

// https://stackoverflow.com/questions/6274339/how-can-i-shuffle-an-array
const shuffle = (a) => {
    for (let i = a.length - 1; i > 0; i--) {
        const j = Math.floor(Math.random() * (i + 1));
        [a[i], a[j]] = [a[j], a[i]];
    }
    return a;
}


console.time('seed');
let a = Array.from(Array(20000)).map(() => ({
  id: f.random.uuid(),
  name: f.name.findName(),
  about: f.lorem.paragraphs(1),
  tags: [f.lorem.word(), f.lorem.word(), f.lorem.word()]
}));

a = shuffle([...a, ...dup(a), ...dup(a)]);
console.timeEnd('seed');

let u = [];
console.time('reduce');
u = a.reduce((acc, el) => acc.find(it => it.id === el.id) ? acc : acc.concat(el), []);
console.timeEnd('reduce');

u = [];
console.time('for-of');
for (let el of a) {
  if (!u.find(it => it.id === el.id)) u.push(el);
}
console.timeEnd('for-of');

u = []; 
console.time('set');
const s = new Set();
for (let el of a) {
  if (!s.has(el.id)) {
    u.push(el);
    s.add(el.id);
  }
}
console.timeEnd('set');

u = []; 
console.time('map');
const m = new Map();
for (let el of a) m.set(el.id, el);
u = m.values();
console.timeEnd('map');

console.time('object');
const o = {};
for (let el of a) o[el.id] = el;
u = Object.values(o);
console.timeEnd('object');

// can only check whether the weak set contains the object or not but actually iterate over
console.time('weakSet');
const ws = new WeakSet();
for (let el of a) ws.add(el);
console.timeEnd('weakSet');