Benchmark: forEach concat vs reduce push performance

Tests:

forEach concat
const a = [...Array(1000)].map(() => ({ nested: Array.from({length: 40}, () => Math.floor(Math.random() * 40)) })); let b = []; a.forEach((item) => { b = b.concat(item.nested); });
Reduce push
const a = [...Array(1000)].map(() => ({ nested: Array.from({length: 40}, () => Math.floor(Math.random() * 40)) })); const b = a.reduce((acc, item) => { acc.push(...item.nested); return acc }, []);

Rendered benchmark preparation results:

Previous results

Test case name	Result
forEach concat
Reduce push

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36 Edg/96.0.1054.62

Browser/OS: Chrome 96 on Windows

Test name	Executions per second
forEach concat	20.4 Ops/sec
Reduce push	54.3 Ops/sec

forEach concat vs reduce push performance (version: 0)