Run results for: Object.keys + map vs for...in + push

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0

Browser: Chrome 126

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Object.keys + map	372467.9 Ops/sec
for...in + push	245995.8 Ops/sec

Script Preparation code:

var data = [
  {
    "SDGHDJJ": "FDSFSDF",
    "FDSDS": "GFDGFDG",
    "5SDFFD": "GFDGDFG",
    "353G": "THFGJGFGF",
    "6BDFSD": "GFDDWERT",
    "53523FV": "HGFHGFHFGHF",
    "FSDGSDGS4": "FDSFDTYF",
    "532523GSV": "SADAHHDFG",
    "253GSG": "GFDGDFHDF",
    "ADFGJKU5": "GDFJKTRRW",
    "354GFG": "DSFSDHRRR"
  }
];
var result = [];

Tests:

Object.keys + map
result = Object.keys(data[0]).map(prop => ( { wch: Math.max(prop.toString().length, ...data.map(obj => obj[prop] ? obj[prop].toString().length : 0)) } ));
for...in + push
for (const prop in data[0]) { const maxWidth = Math.max(prop.toString().length, ...data.map(obj => obj[prop] ? obj[prop].toString().length : 0)); result.push({ wch: maxWidth }); }