Symfony\Component\Security\Http\RememberMe\AbstractRememberMeServices::autoLogin PHP Method

    final public function autoLogin(Request $request)
    {
        if (null === $cookie = $request->cookies->get($this->options['name'])) {
            return;
        }

        if (null !== $this->logger) {
            $this->logger->debug('Remember-me cookie detected.');
        }

        $cookieParts = $this->decodeCookie($cookie);

        try {
            $user = $this->processAutoLoginCookie($cookieParts, $request);

            if (!$user instanceof UserInterface) {
                throw new \RuntimeException('processAutoLoginCookie() must return a UserInterface implementation.');
            }

            if (null !== $this->logger) {
                $this->logger->info('Remember-me cookie accepted.');
            }

            return new RememberMeToken($user, $this->providerKey, $this->key);
        } catch (CookieTheftException $theft) {
            $this->cancelCookie($request);

            throw $theft;
        } catch (UsernameNotFoundException $notFound) {
            if (null !== $this->logger) {
                $this->logger->info('User for remember-me cookie not found.');
            }
        } catch (UnsupportedUserException $unSupported) {
            if (null !== $this->logger) {
                $this->logger->warn('User class for remember-me cookie not supported.');
            }
        } catch (AuthenticationException $invalid) {
            if (null !== $this->logger) {
                $this->logger->debug('Remember-Me authentication failed: '.$invalid->getMessage());
            }
        }

        $this->cancelCookie($request);

        return null;
    }