bug symfony#50813 [DoctrineBridge] Load refreshed user proxy (MatTheCat)

This PR was merged into the 5.4 branch.

Discussion
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[DoctrineBridge] Load refreshed user proxy

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix symfony#50758
| License       | MIT
| Doc PR        | N/A

When [exiting impersonation](https://github.com/symfony/symfony/blob/529973b88db84aee4e962b2ba8bb1838bbbe6a38/src/Symfony/Component/Security/Http/Firewall/SwitchUserListener.php#L210), the impersonator get refreshed in the original token. Problem is, the refreshed user can be a proxy if it is referenced by the impersonated. In that case, all its properties (except identifiers) will be `null` when it is unserialised by the `ContextListener`.

The refreshed user data will be needed anyways, so loading proxies in `EntityUserProvider::refreshUser` should not impact performance.

Commits
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6f53d54 [DoctrineBridge] Load refreshed user proxy

Author: nicolas-grekas

src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php

@@ -15,6 +15,7 @@
 use Doctrine\Persistence\Mapping\ClassMetadata;
 use Doctrine\Persistence\ObjectManager;
 use Doctrine\Persistence\ObjectRepository;
+use Doctrine\Persistence\Proxy;
 use Symfony\Component\Security\Core\Exception\UnsupportedUserException;
 use Symfony\Component\Security\Core\Exception\UserNotFoundException;
 use Symfony\Component\Security\Core\User\PasswordAuthenticatedUserInterface;
@@ -117,6 +118,10 @@ public function refreshUser(UserInterface $user)
             }
         }
 
+        if ($refreshedUser instanceof Proxy && !$refreshedUser->__isInitialized()) {
+            $refreshedUser->__load();
+        }
+
         return $refreshedUser;
     }
 

src/Symfony/Bridge/Doctrine/Tests/Security/User/EntityUserProviderTest.php

@@ -16,6 +16,7 @@
 use Doctrine\Persistence\ManagerRegistry;
 use Doctrine\Persistence\ObjectManager;
 use Doctrine\Persistence\ObjectRepository;
+use Doctrine\Persistence\Proxy;
 use PHPUnit\Framework\TestCase;
 use Symfony\Bridge\Doctrine\Security\User\EntityUserProvider;
 use Symfony\Bridge\Doctrine\Security\User\UserLoaderInterface;
@@ -197,6 +198,27 @@ public function testPasswordUpgrades()
         $provider->upgradePassword($user, 'foobar');
     }
 
+    public function testRefreshedUserProxyIsLoaded()
+    {
+        $em = DoctrineTestHelper::createTestEntityManager();
+        $this->createSchema($em);
+
+        $user = new User(1, 1, 'user1');
+
+        $em->persist($user);
+        $em->flush();
+        $em->clear();
+
+        // store a proxy in the identity map
+        $em->getReference(User::class, ['id1' => 1, 'id2' => 1]);
+
+        $provider = new EntityUserProvider($this->getManager($em), User::class);
+        $refreshedUser = $provider->refreshUser($user);
+
+        $this->assertInstanceOf(Proxy::class, $refreshedUser);
+        $this->assertTrue($refreshedUser->__isInitialized());
+    }
+
     private function getManager($em, $name = null)
     {
         $manager = $this->createMock(ManagerRegistry::class);