Benchmark: Concatenation - MeasureThat.net

Script Preparation code:

var str = "";
var i;
var sArr = [];

Tests:

Join
for (i = 1000; i > 0; i--) { sArr[i] = "String concatenation. "; } str = sArr.join("");
Push & Join
for (i = 1000; i > 0; i--) { sArr.push("String concatenation. "); } str = sArr.join("");
Reduce
for (i = 1000; i > 0; i--) { sArr.push("String concatenation. "); } str = sArr.reduce((a, v) => a += `${v} `, '');
Reduce & Trim
for (i = 1000; i > 0; i--) { sArr.push("String concatenation. "); } str = sArr.reduce((a, v) => a += `${v} `, '').trim();
Array expression & Reduce
for (i = 1000; i > 0; i--) { sArr = [ ...sArr, "String concatenation. " ]; } str = sArr.reduce((a, v) => a += `${v} `, '');

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1.2 Safari/605.1.15

Browser/OS: Safari 13 on Mac OS X 10.15.6

Concatenation (version: 0)