Run results for: Intl.DateTimeFormat vs ReduceReplace Date Format 2

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36

Browser: Chrome 81

Operating system: Linux

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Intl.DateTimeFormat	12801.2 Ops/sec
Reduce/Replace Format	312137.7 Ops/sec
Reduce/Replace Format multiple new Date calls	15433920.0 Ops/sec

Script Preparation code:

var date = 'Mar 24, 2021'

var formatDateByIntlDateTimeFormat = (dateOrString) => {
  return new Intl.DateTimeFormat('pt-BR').format(new Date(dateOrString))
}

var tokens = {
  // Padded day       = 01, 02, ..., 31
  DD: (date) => date.getDate().toString().padStart(2, '0'),
  // Padded month     = 01, 02, ..., 12
  MM: (date) => (date.getMonth() + 1).toString().padStart(2, '0'),
  // Padded year      = 0001, 0002, ..., 1995, ..., 2020, 2021
  YYYY: (date) => date.getFullYear().toString().padStart(4, '0'),
};

var formatDateByReduceReplace = (dateOrString, format = 'DD/MM/YYYY') => {
  const date = new Date(dateOrString)
  return Object.entries(tokens).reduce(
    (result, [pattern, fn]) => result.replace(new RegExp(pattern, 'g'), fn(date)),
    format
  );
};

var formatDateByReduceReplaceMultipleNewDate = (dateOrString, format = 'DD/MM/YYYY') => {
  return Object.entries(tokens).reduce(
    (result, [pattern, fn]) => result.replace(new RegExp(pattern, 'g'), fn(new Date(dateOrString))),
    format
  );
};

Tests:

Intl.DateTimeFormat
formatDateByIntlDateTimeFormat(date)
Reduce/Replace Format
formatDateByReduceReplace(date, 'DD/MM/YYYY')
Reduce/Replace Format multiple new Date calls
formatDateByReduceReplaceMultipleNewDate(date)

Run results for: Intl.DateTimeFormat vs ReduceReplace Date Format 2

Intl.DateTimeFormat

Reduce/Replace Format

Reduce/Replace Format multiple new Date calls