Function createDate

packages/common/src/i18n/format_date.ts:180–200

* Create a new Date object with the given date value, and the time set to midnight. * * We cannot use `new Date(year, month, date)` because it maps years between 0 and 99 to 1900-1999. * See: https://github.com/angular/angular/issues/40377 * * Note that this function returns a Date object whose

(year: number, month: number, date: number)

 * considerable breaking change.
 */
function createDate(year: number, month: number, date: number): Date {
  // The `newDate` is set to midnight (UTC) on January 1st 1970.
  // - In PST this will be December 31st 1969 at 4pm.
  // - In GMT this will be January 1st 1970 at 1am.
  // Note that they even have different years, dates and months!
  const newDate = new Date(0);

  // `setFullYear()` allows years like 0001 to be set correctly. This function does not
  // change the internal time of the date.
  // Consider calling `setFullYear(2019, 8, 20)` (September 20, 2019).
  // - In PST this will now be September 20, 2019 at 4pm
  // - In GMT this will now be September 20, 2019 at 1am

  newDate.setFullYear(year, month, date);
  // We want the final date to be at local midnight, so we reset the time.
  // - In PST this will now be September 20, 2019 at 12am
  // - In GMT this will now be September 20, 2019 at 12am
  newDate.setHours(0, 0, 0);

  return newDate;
}

function getNamedFormat(locale: string, format: string): string {
  const localeId = getLocaleId(locale);