Run results for: immer push vs spread

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:142.0) Gecko/20100101 Firefox/142.0

Browser: Firefox 142

Operating system: Windows

Device Platform: Desktop

Date tested: 8 months ago

spread

2.1M/s

immer

92K/s

View exact numbers

Test name	Executions per second
✓ spread	2,063,002 Ops/sec
immer	92,433 Ops/sec

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/immer@9.0.13/dist/immer.umd.production.min.js"></script>

Script Preparation code:

const createList = () => 
  Array.from({ length: 100 }, (_, i) => ({ id: i, value: `Item ${i}` }));

const list = createList();
const nextItem = { id: "x", value: "I'm next" };

Tests:

immer
const updatedList = immer.produce(list, (draft) => { draft.push(nextItem); });
spread
const updatedList = [...list, nextItem];