Merge branch '4.4' into 5.4

* 4.4:
  [FrameworkBundle] Fix resetting container between tests

Author: nicolas-grekas

KernelBrowser.php

@@ -22,7 +22,6 @@
 use Symfony\Component\HttpKernel\KernelInterface;
 use Symfony\Component\HttpKernel\Profiler\Profile as HttpProfile;
 use Symfony\Component\Security\Core\User\UserInterface;
-use Symfony\Contracts\Service\ResetInterface;
 
 /**
  * Simulates a browser and makes requests to a Kernel object.
@@ -168,12 +167,8 @@ protected function doRequest(object $request)
         // avoid shutting down the Kernel if no request has been performed yet
         // WebTestCase::createClient() boots the Kernel but do not handle a request
         if ($this->hasPerformedRequest && $this->reboot) {
-            $container = $this->kernel->getContainer();
+            $this->kernel->boot();
             $this->kernel->shutdown();
-
-            if ($container instanceof ResetInterface) {
-                $container->reset();
-            }
         } else {
             $this->hasPerformedRequest = true;
         }

Test/KernelTestCase.php

@@ -15,7 +15,6 @@
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException;
 use Symfony\Component\HttpKernel\KernelInterface;
-use Symfony\Contracts\Service\ResetInterface;
 
 /**
  * KernelTestCase is the base class for tests needing a Kernel.
@@ -42,8 +41,6 @@ abstract class KernelTestCase extends TestCase
 
     protected static $booted = false;
 
-    private static $kernelContainer;
-
     protected function tearDown(): void
     {
         static::ensureKernelShutdown();
@@ -80,11 +77,12 @@ protected static function bootKernel(array $options = [])
     {
         static::ensureKernelShutdown();
 
-        static::$kernel = static::createKernel($options);
-        static::$kernel->boot();
+        $kernel = static::createKernel($options);
+        $kernel->boot();
+        self::$kernel = $kernel;
         static::$booted = true;
 
-        self::$kernelContainer = $container = static::$kernel->getContainer();
+        $container = static::$kernel->getContainer();
         static::$container = $container->has('test.service_container') ? $container->get('test.service_container') : $container;
 
         return static::$kernel;
@@ -156,14 +154,11 @@ protected static function createKernel(array $options = [])
     protected static function ensureKernelShutdown()
     {
         if (null !== static::$kernel) {
+            static::$kernel->boot();
             static::$kernel->shutdown();
             static::$booted = false;
         }
 
-        if (self::$kernelContainer instanceof ResetInterface) {
-            self::$kernelContainer->reset();
-        }
-
-        static::$container = self::$kernelContainer = null;
+        static::$container = null;
     }
 }

Tests/KernelBrowserTest.php

@@ -51,6 +51,16 @@ public function testEnableRebootKernel()
         $client->request('GET', '/');
     }
 
+    public function testRequestAfterKernelShutdownAndPerformedRequest()
+    {
+        $this->expectNotToPerformAssertions();
+
+        $client = static::createClient(['test_case' => 'TestServiceContainer']);
+        $client->request('GET', '/');
+        static::ensureKernelShutdown();
+        $client->request('GET', '/');
+    }
+
     private function getKernelMock()
     {
         $mock = $this->getMockBuilder($this->getKernelClass())