bug symfony#45671 [FrameworkBundle] Ensure container is reset between tests (nicolas-grekas)

This PR was merged into the 4.4 branch.

Discussion
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[FrameworkBundle] Ensure container is reset between tests

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix symfony#45668
| License       | MIT
| Doc PR        | -

Calling boot() resets the container only is a request was handled before.
Since this is not always the case here, we need to reset the container explicitly.

Commits
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608b1dd [FrameworkBundle] Ensure container is reset between tests

Author: nicolas-grekas

src/Symfony/Bundle/FrameworkBundle/Test/KernelTestCase.php

@@ -14,6 +14,7 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpKernel\KernelInterface;
+use Symfony\Contracts\Service\ResetInterface;
 
 /**
  * KernelTestCase is the base class for tests needing a Kernel.
@@ -131,8 +132,13 @@ protected static function ensureKernelShutdown()
     {
         if (null !== static::$kernel) {
             static::$kernel->boot();
+            $container = static::$kernel->getContainer();
             static::$kernel->shutdown();
             static::$booted = false;
+
+            if ($container instanceof ResetInterface) {
+                $container->reset();
+            }
         }
 
         static::$container = null;