jQuery form error checking

I'm doing a simple jQuery form checker for a website. I have two forms on the website: a login form and a signup form. My code is as followed:

$('.btn').click(function(e) {
     e.preventDefault();
     // DOES SOME ERROR CHECKING HERE
     if { hasError $('div.error').fadeIn() }
 
     else { $(this).parents('form').submit() }
 });
 

So my question is, both the login button and the signup button has a class called btn, how can I have the them check their own form instead of checking all the forms on the page since $(this).parents('form') will get both the signup and login form?

Thank you!

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