title: Rails custom validation one after another
body: <p>I have a password field and that validates <code>presence</code> and <code>length</code> and both are working fine. But when I submit the form with blank password field, it displays error messages for both validations. </p>
  
  <p>What I want is if the password is blank then <code>length</code> validator must not checked and display error message for only <code>presence</code> validator. Length validator will only be checked if password is present.</p>