Benchmarking JavaScript Arrays and Sets

js-array-vs-set.js

let arr = [], set = new Set(), n = 1000000;

for (let i = 0; i < n; i++) {
    arr.push(i);
    set.add(i);
}

function checkArr(arr, value) {
    return arr.indexOf(value);
}

function checkSet(set, value) {
    return set.has(value);
}

console.log('\nFind a value:')
console.time('Array');
result = checkArr(arr, 123123);
console.timeEnd('Array');
console.time('Set');
result = checkSet(set, 123123);
console.timeEnd('Set');

console.log('\nAdd values:')
const numbersToAdd = n + 1001;
console.time('Array');
for (let i = n + 1; i < numbersToAdd; i++) {
    arr.push(i);
}
console.timeEnd('Array');
console.time('Set');
for (let i = n + 1; i < numbersToAdd; i++) {
    set.add(i);
}
console.timeEnd('Set');

console.log('\nRemove a value:')
const deleteFromArr = (arr, item) => {
    let index = arr.indexOf(item);
    return index !== -1 && arr.splice(index, 1);
};

console.time('Array');
deleteFromArr(arr, n);
console.timeEnd('Array');
console.time('Set');
set.delete(n);
console.timeEnd('Set');

console.log('\nDedupe collection:')
const duplicateCollection = ['A', 'B', 'B', 'C', 'D', 'B', 'C'];
// If you want to turn the array into a Set
console.time('Set dedupe');
let uniqueCollection = new Set(duplicateCollection);
console.timeEnd('Set dedupe');
console.log(uniqueCollection) // Result: Set(4) {"A", "B", "C", "D"}
// If you want to keep your values in an array
console.time('Set dedupe into array');
uniqueCollection = [...new Set(duplicateCollection)];
console.timeEnd('Set dedupe into array');
console.log(uniqueCollection) // Result: ["A", "B", "C", "D"]