add more default Kernel class names to DefaultAnalyzedSymfonyApplicationContainer [closes #468]

src/Bridge/Symfony/DefaultAnalyzedSymfonyApplicationContainer.php

@@ -58,10 +58,26 @@ final class DefaultAnalyzedSymfonyApplicationContainer implements AnalyzedApplic
     private function getContainer(): Container
     {
         $kernelClass = $this->parameterProvider->provideParameter(Option::KERNEL_CLASS_PARAMETER);
+        if ($kernelClass === null) {
+            $kernelClass = $this->getDefaultKernelClass();
+        }
 
         $this->symfonyKernelParameterGuard->ensureKernelClassIsValid($kernelClass);
 
         /** @var string $kernelClass */
         return $this->containerFactory->createFromKernelClass($kernelClass);
     }
+
+    private function getDefaultKernelClass(): ?string
+    {
+        $possibleKernelClasses = ['App\Kernel', 'Kernel', 'AppKernel'];
+
+        foreach ($possibleKernelClasses as $possibleKernelClass) {
+            if (class_exists($possibleKernelClass)) {
+                return $possibleKernelClass;
+            }
+        }
+
+        return null;
+    }
 }

src/config/config.yml

@@ -1,7 +1,3 @@
-parameters:
-    # default Symfony Kernel class
-    kernel_class: 'App\Kernel'
-
 imports:
   - { resource: '../../packages/**/src/config/*services.yml' }
   - { resource: 'services.yml' }

tests/Rector/Contrib/Symfony/FrameworkBundle/GetToConstructorInjectionRector/InvalidConfigurationConstructorInjectionRectorTest.php

@@ -13,10 +13,7 @@ final class InvalidConfigurationConstructorInjectionRectorTest extends AbstractR
     public function test(): void
     {
         $this->expectException(InvalidConfigurationException::class);
-        $this->expectExceptionMessage(
-            'Kernel class "App\Kernel" provided in "parameters > kernel_class" is not autoloadable.'
-            . ' Make sure composer.json of your application is valid and rector is loading "vendor/autoload.php" of your application.'
-        );
+        $this->expectExceptionMessage('Make sure "kernel_class" parameters is set in rector.yml in "parameters:" section');
 
         $this->doTestFileMatchesExpectedContent(__DIR__ . '/Wrong/wrong.php.inc', __DIR__ . '/Correct/correct.php.inc');
     }