Benchmark: spread vs concat vs unshift (fair) to join arrays

Script Preparation code:

var a = [1,2,3];
var b = [4,5,6];

Tests:

spread
b=[...a,...b];
concat
b=a.concat(b);
unshift (forEach)
var c = []; a.forEach(el => c.unshift(el)) b.forEach(el => c.unshift(el))
unshift (spread)
var c = []; c.unshift(...a); c.unshift(...b);
push (forEach)
var c = []; a.forEach(el => c.push(el)) b.forEach(el => c.push(el))
push (spread)
var c = []; c.push(...a); c.push(...b);

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:100.0) Gecko/20100101 Firefox/100.0

Browser/OS: Firefox 100 on Linux

spread vs concat vs unshift (fair) to join arrays (version: 2)