symfony 授权时出错

在命令的帮助下make:auth创建了授权。用用户填满表格。当我尝试登录时，我收到一条错误消息：

There is no user provider for user "App\Entity\User". Shouldn't the "supportsClass()" method of your user provider return true for this classname?

怎么了？似乎我按照文档https://symfony.com/doc/current/security/form_login_setup.html中的指示做了所有事情

我的安全.yaml

    encoders:
        App\Entity\User:
            algorithm: bcrypt
            cost: 12
    # https://symfony.com/doc/current/security.html#where-do-users-come-from-user-providers
    providers:
        in_memory: { memory: null }
    firewalls:
        dev:
            pattern: ^/(_(profiler|wdt)|css|images|js)/
            security: false
        main:
            anonymous: lazy
            guard:
                authenticators:
                    - App\Security\LoginFormAuthenticator
            logout:
                path: app_logout
                # where to redirect after logout
                # target: app_any_route

            # activate different ways to authenticate
            # https://symfony.com/doc/current/security.html#firewalls-authentication

            # https://symfony.com/doc/current/security/impersonating_user.html
            # switch_user: true

    # Easy way to control access for large sections of your site
    # Note: Only the *first* access control that matches will be used
    access_control:
        # - { path: ^/admin, roles: ROLE_ADMIN }
        # - { path: ^/profile, roles: ROLE_USER }

Guard（表单处理）

namespace App\Security;

use App\Entity\User;
use Doctrine\ORM\EntityManagerInterface;
use Symfony\Component\HttpFoundation\RedirectResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
use Symfony\Component\Security\Core\Encoder\UserPasswordEncoderInterface;
use Symfony\Component\Security\Core\Exception\CustomUserMessageAuthenticationException;
use Symfony\Component\Security\Core\Exception\InvalidCsrfTokenException;
use Symfony\Component\Security\Core\Security;
use Symfony\Component\Security\Core\User\UserInterface;
use Symfony\Component\Security\Core\User\UserProviderInterface;
use Symfony\Component\Security\Csrf\CsrfToken;
use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
use Symfony\Component\Security\Guard\Authenticator\AbstractFormLoginAuthenticator;
use Symfony\Component\Security\Guard\PasswordAuthenticatedInterface;
use Symfony\Component\Security\Http\Util\TargetPathTrait;

class LoginFormAuthenticator extends AbstractFormLoginAuthenticator implements PasswordAuthenticatedInterface
{
    use TargetPathTrait;

    private $entityManager;
    private $urlGenerator;
    private $csrfTokenManager;
    private $passwordEncoder;

    public function __construct(EntityManagerInterface $entityManager, UrlGeneratorInterface $urlGenerator, CsrfTokenManagerInterface $csrfTokenManager, UserPasswordEncoderInterface $passwordEncoder)
    {
        $this->entityManager = $entityManager;
        $this->urlGenerator = $urlGenerator;
        $this->csrfTokenManager = $csrfTokenManager;
        $this->passwordEncoder = $passwordEncoder;
    }

    public function supports(Request $request)
    {
        return 'app_login' === $request->attributes->get('_route')
            && $request->isMethod('POST');
    }

    public function getCredentials(Request $request)
    {
        $credentials = [
            'email' => $request->request->get('email'),
            'password' => $request->request->get('password'),
            'csrf_token' => $request->request->get('_csrf_token'),
        ];
        $request->getSession()->set(
            Security::LAST_USERNAME,
            $credentials['email']
        );

        return $credentials;
    }

    public function getUser($credentials, UserProviderInterface $userProvider)
    {
        $token = new CsrfToken('authenticate', $credentials['csrf_token']);
        if (!$this->csrfTokenManager->isTokenValid($token)) {
            throw new InvalidCsrfTokenException();
        }

        $user = $this->entityManager->getRepository(User::class)->findOneBy(['email' => $credentials['email']]);

        if (!$user) {
            // fail authentication with a custom error
            throw new CustomUserMessageAuthenticationException('Email could not be found.');
        }

        return $user;
    }

    public function checkCredentials($credentials, UserInterface $user)
    {
        return $this->passwordEncoder->isPasswordValid($user, $credentials['password']);
    }

    /**
     * Used to upgrade (rehash) the user's password automatically over time.
     */
    public function getPassword($credentials): ?string
    {
        return $credentials['password'];
    }

    public function onAuthenticationSuccess(Request $request, TokenInterface $token, $providerKey)
    {
        if ($targetPath = $this->getTargetPath($request->getSession(), $providerKey)) {
            return new RedirectResponse($targetPath);
        }

        // For example : return new RedirectResponse($this->urlGenerator->generate('some_route'));
        //throw new \Exception('TODO: provide a valid redirect inside '.__FILE__);

        return new RedirectResponse($this->urlGenerator->generate('app_homepage'));


    }

    protected function getLoginUrl()
    {
        return $this->urlGenerator->generate('app_login');
    }
}

PS在此之前，我在 UserProvider 中编辑了supportsClass，使其不返回false：

{
    return $class === UserIdentity::class;
}