Run results for: Spread operator vs. Array.map and lodash.set

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 12_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/74.0.3729.121 Mobile/15E148 Safari/605.1

Browser: Chrome Mobile iOS 74

Operating system: iOS 12.2

Device Platform: Mobile

Date tested: 5 years ago

Test name	Executions per second
Spread operator	19636.5 Ops/sec
Spread operator v2	16564.1 Ops/sec

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

permutations = new Array(10000).map(() => ({ pagination: 'blah blah blah' }));
function updatePagination(action, prev) {
  return action;
}
action = 'something else';
state = { data: { permutations: [] } };
index = 5;

Tests:

Spread operator
const updated = Object.assign([...permutations], { [index]: Object.assign({}, permutations[index], { pagination: updatePagination(action, permutations[index]) }) }) return { ...state, data: { ...state.data, permutations: updated } };
Spread operator v2
const updated = Object.assign([...permutations], { [index]: { ...permutations[index], pagination: updatePagination(action, permutations[index]) } }) return { ...state, data: { ...state.data, permutations: updated } };

Run results for: Spread operator vs. Array.map and lodash.set

A comparison of the performance of the spread operator, [ ...array ], vs. Array.map(i => ...) and

Spread operator

Spread operator v2