PHPMailer::sanitiseDate( DateTime|DateTimeImmutable|string $date ): string

4477    private static function sanitiseDate($date)4478    {4479        try {4480            //Ensure the default timezone is set properly4481            date_default_timezone_set(@date_default_timezone_get());4482 4483            if ($date instanceof \DateTimeInterface) {4484                $dt = $date;4485            } elseif (is_string($date) && $date !== '') {4486                $dt = new \DateTime($date);4487            } else {4488                //Empty string, null, or any unsupported type4489                return self::rfcDate();4490            }4491 4492            //Reject future dates — they are invalid for outgoing message headers4493            if ($dt->getTimestamp() > time()) {4494                return self::rfcDate();4495            }4496 4497            return $dt->format(self::RFC822_DATE_FORMAT);4498        } catch (\Exception $e) {4499            return self::rfcDate();4500        }4501    }