Prevent e-Mails from being sent out

gistfile1.txt

function childtheme_no_emails( &$phpmailer ) {
    // Empty out the values that may be set
    $phpmailer->ClearAllRecipients();
    $phpmailer->ClearAttachments();
    $phpmailer->ClearCustomHeaders();
    $phpmailer->ClearReplyTos();
}
add_action( 'phpmailer_init', 'childtheme_no_emails', 99, 1 );