onSubmit submits form if handler function has error

I have <form #signInForm="ngForm" (ngSubmit)="onSubmit($event)"> whish is just basic sign in form, when error occurs in onSubmit method it just submits the form. There’s no possibility of preventing default action at first as $event is just null

[DzmitryShylovich]

http://prntscr.com/cpg2tl

[angular-automatic-lock-bot[bot]]

This issue has been automatically locked due to inactivity. Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}