CakePHP 3: Migrating from scope to finder (auth)

cake3auth_finder.php

<?php
// src/Controller/AppController.php
$this->loadComponent('Auth', [
  'authenticate' => [
      'Form' => [
          'fields' => [
              'username' => 'email',
              'password' => 'password'
          ],
          // Older "scope" / "contain"
          'finder' => 'auth'
      ]
    ]
  ]
);

// src/Model/Table/Users.php
public function findAuth(\Cake\ORM\Query $query, array $options)
{
    $query
        // ->select(['id', 'email', 'password'])
        ->where(['Users.active' => 1]);

    return $query;
}

<?php
<?php
public function login()
{
    if ($this->request->is('post')) {
        if (!$this->Users->findByUsername($this->request->data['username'])->count()) {
            $this->Flash->error(__('The username you provided does not belong to any registered account. Please correct the username.'), ['key' => 'auth']);
            // Redirect here
        }

        $user = $this->Auth->identify();
        if ($user) {
            if (!$user['verified']) {
                $this->Flash->error(__('Your account is not yet verified. Please check your email inbox to find the registration email we sent you.'), ['key' => 'auth']);
                // another redirect here
            }
            $this->Auth->setUser($user);
            return $this->redirect($this->Auth->redirectUrl());
        }
        $this->Flash->error(__('You have provided the wrong password. Please try again.'), ['key' => 'auth']);
    }
}