performance

index.js

// Diy Date
/**
 * @param {Date} date
 */
function getDiyDate(date) {
  const year = date.getFullYear();
  const month = date.getMonth() + 1;
  const monthString = month < 10 ? `0${month}` : month;
  const day = date.getDate();
  const dayString = day < 10 ? `0${day}` : day;
  const hours = date.getHours();
  const minutes = date.getMinutes();
  const hoursShort = hours % 12;
  const hoursString = hoursShort < 10 ? `0${hoursShort}` : hoursShort;
  const minutesString = minutes < 10 ? `0${minutes}` : minutes;
  const timeOfDay = hours < 12 ? "AM" : "PM";

  return `${monthString}/${dayString}/${year}, ${hoursString}:${minutesString} ${timeOfDay}`;
}
// /Diy Date

// Internationalization formatted date
const intlFormatter = new Intl.DateTimeFormat("en-US", {
  day: "2-digit",
  month: "2-digit",
  year: "numeric",
  hour: "2-digit",
  minute: "2-digit",
});
// /Internationalization formatted date

const iter = 100000;

// warmup
console.log("warmup starting");

for (let i = iter; i--; ) {
  getDiyDate(new Date("2023-11-21T00:00:00.000Z"));
}

for (let i = iter; i--; ) {
  intlFormatter.format(Date.parse("2023-11-21T00:00:00.000Z"));
}

console.log("warmup done");
// /warmup

// actual test
const startDiy = performance.now();
const diyDate = getDiyDate(new Date("2023-11-21T00:00:00.000Z"));
const endDiy = performance.now();

const startIntl = performance.now();
const intlDate = intlFormatter.format(Date.parse("2023-11-21T00:00:00.000Z"));
const endIntl = performance.now();
// /actual test

// results
console.log(
  `getDiyDates  took ${(endDiy - startDiy).toFixed(20)} milliseconds,`,
  diyDate
);
console.log(
  `getIntlDates took ${(endIntl - startIntl).toFixed(20)} milliseconds,`,
  intlDate
);

const date = new Date("2023-11-21T00:00:00.000Z");
const iter2 = 100000;

// warmup
console.log("warmup starting");

for (let i = iter2; i--; ) {
  getDiyDate(date);
}

for (let i = iter2; i--; ) {
  intlFormatter.format(date);
}

console.log("warmup done");
// /warmup

// actual test
const startDiy2 = performance.now();
const diyDate2 = getDiyDate(date);
const endDiy2 = performance.now();

const startIntl2 = performance.now();
const intlDate2 = intlFormatter.format(date);
const endIntl2 = performance.now();
// /actual test

// results
console.log(
  `getDiyDates  took ${(endDiy2 - startDiy2).toFixed(20)} milliseconds,`,
  diyDate2
);
console.log(
  `getIntlDates took ${(endIntl2 - startIntl2).toFixed(20)} milliseconds,`,
  intlDate2
);

/*
node ./index.js

warmup starting
warmup done
getDiyDates  took 0.01456000003963708878 milliseconds, 11/21/2023, 01:00 AM
getIntlDates took 0.00782100018113851547 milliseconds, 11/21/2023, 01:00 AM
warmup starting
warmup done
getDiyDates  took 0.00626999977976083755 milliseconds, 11/21/2023, 01:00 AM
getIntlDates took 0.00490000005811452866 milliseconds, 11/21/2023, 01:00 AM
*/