KernelTestCase resets internal state on tearDown

Author: core23

Test/KernelTestCase.php

@@ -44,6 +44,7 @@ abstract class KernelTestCase extends TestCase
     private function doTearDown()
     {
         static::ensureKernelShutdown();
+        static::$class = null;
         static::$kernel = null;
         static::$booted = false;
     }

Tests/Functional/TestServiceContainerTest.php

@@ -44,4 +44,22 @@ public function testThatPrivateServicesAreAvailableIfTestConfigIsEnabled()
         $this->assertTrue(static::$container->has('private_service'));
         $this->assertFalse(static::$container->has(UnusedPrivateService::class));
     }
+
+    /**
+     * @doesNotPerformAssertions
+     */
+    public function testBootKernel()
+    {
+        static::bootKernel(['test_case' => 'TestServiceContainer']);
+    }
+
+    /**
+     * @depends testBootKernel
+     */
+    public function testKernelIsNotInitialized()
+    {
+        self::assertNull(self::$class);
+        self::assertNull(self::$kernel);
+        self::assertFalse(self::$booted);
+    }
 }