Function defaultTimezone

packages/utils/defaultTimezone.ts:37–58

(
  locales?: DTFParameters[0],
  options?: Pick<Intl.DateTimeFormatOptions, 'timeZoneName'>
)

 * @returns default timezone for the system
 */
export function defaultTimezone(
  locales?: DTFParameters[0],
  options?: Pick<Intl.DateTimeFormatOptions, 'timeZoneName'>
): string {
  const timeZoneName = options?.timeZoneName
  try {
    const dtf = getDateTimeFormat(locales, {
      timeZoneName: options?.timeZoneName,
    })
    // If there's no `timeZoneName` specified, return the IANA timezone name
    if (!timeZoneName) {
      return dtf.resolvedOptions().timeZone
    }
    // If `timeZoneName` is specified, return the localized timezone name
    return (
      dtf.formatToParts(now).find(p => p.type === 'timeZoneName')?.value ||
      'UTC'
    )
  } catch {
    return 'UTC'
  }
}