Cake\Localized\Validation\NoValidation::postal PHP Method

    public static function postal($check)
    {
        $pattern = '/^\\d{4}$/';
        return (bool) preg_match($pattern, $check);
    }

 /**
  * test the postal method of NoValidation
  *
  * @return void
  */
 public function testPostal()
 {
     $this->assertTrue(NoValidation::postal('0123'));
     $this->assertFalse(NoValidation::postal('90210'));
 }