Ouzo\Utilities\Date::addInterval PHP Метод

    public static function addInterval($interval, $format = self::DEFAULT_TIME_FORMAT)
    {
        $date = Clock::now()->toDateTime();
        $date->add(new DateInterval($interval));
        return $date->format($format);
    }

 /**
  * @test
  */
 public function shouldAddIntervalToCurrentDate()
 {
     //when
     $date = Date::addInterval('P2Y');
     //then
     $this->assertGreaterThan(Clock::nowAsString(), $date);
 }