diff --git a/tests/BiomeJsBinaryTest.php b/tests/BiomeJsBinaryTest.php
index 2558198..051f5c8 100644
--- a/tests/BiomeJsBinaryTest.php
+++ b/tests/BiomeJsBinaryTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace Kocal\BiomeJsBundle\Tests;
@@ -13,7 +14,7 @@ final class BiomeJsBinaryTest extends TestCase
 {
     public function testBinaryIsDownloadedIfNotExists(): void
     {
-        $binaryDownloadDir = __DIR__.'/fixtures/var/download';
+        $binaryDownloadDir = __DIR__ . '/fixtures/var/download';
         $fs = new Filesystem();
         if (file_exists($binaryDownloadDir)) {
             $fs->remove($binaryDownloadDir);
@@ -31,14 +32,14 @@ public function testBinaryIsDownloadedIfNotExists(): void
             $client
         );
         $process = $binary->createProcess(['check', '--apply', '*.{js,ts}']);
-        $this->assertFileExists($binaryDownloadDir.'/fake-version/'.BiomeJsBinary::getBinaryName());
+        $this->assertFileExists($binaryDownloadDir . '/fake-version/' . BiomeJsBinary::getBinaryName());
 
         // Windows doesn't wrap arguments in quotes
         $expectedTemplate = '\\' === \DIRECTORY_SEPARATOR ? '"%s" check --apply *.{js,ts}' : "'%s' 'check' '--apply' '*.{js,ts}'";
 
         $this->assertSame(
-            sprintf($expectedTemplate, $binaryDownloadDir.'/fake-version/'.BiomeJsBinary::getBinaryName()),
+            sprintf($expectedTemplate, $binaryDownloadDir . '/fake-version/' . BiomeJsBinary::getBinaryName()),
             $process->getCommandLine()
         );
     }
-}
\ No newline at end of file
+}
diff --git a/tests/FunctionalTest.php b/tests/FunctionalTest.php
index fa75942..0551822 100644
--- a/tests/FunctionalTest.php
+++ b/tests/FunctionalTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace Kocal\BiomeJsBundle\Tests;
@@ -14,7 +15,7 @@ final class FunctionalTest extends KernelTestCase
     protected function setUp(): void
     {
         $fs = new Filesystem();
-        if (is_dir($biomejsVarDir = __DIR__.'/fixtures/var/biomejs')) {
+        if (is_dir($biomejsVarDir = __DIR__ . '/fixtures/var/biomejs')) {
             $fs->remove($biomejsVarDir);
         }
     }
@@ -22,13 +23,14 @@ protected function setUp(): void
     public function testCommandCheck(): void
     {
         self::bootKernel();
+        self::assertNotNull(self::$kernel);
         $application = new Application(self::$kernel);
 
         $command = $application->find('biomejs:check');
         $commandTester = new CommandTester($command);
 
         $statusCode = $commandTester->execute([
-            'path' => [__DIR__.'/fixtures/'],
+            'path' => [__DIR__ . '/fixtures/'],
         ]);
         self::assertSame(Command::FAILURE, $statusCode, 'The command should return a non-zero exit code');
 
@@ -45,13 +47,14 @@ public function testCommandCheck(): void
     public function testCommandCi(): void
     {
         self::bootKernel();
+        self::assertNotNull(self::$kernel);
         $application = new Application(self::$kernel);
 
         $command = $application->find('biomejs:ci');
         $commandTester = new CommandTester($command);
 
         $statusCode = $commandTester->execute([
-            'path' => [__DIR__.'/fixtures/'],
+            'path' => [__DIR__ . '/fixtures/'],
         ]);
         self::assertSame(Command::FAILURE, $statusCode, 'The command should return a non-zero exit code');
 
@@ -64,4 +67,4 @@ public function testCommandCi(): void
         self::assertStringContainsString('BiomeJsBundle/tests/fixtures/bootstrap.js format', $output);
         self::assertStringContainsString('File content differs from formatting output', $output);
     }
-}
\ No newline at end of file
+}
diff --git a/tests/KocalBiomeJsBundleTest.php b/tests/KocalBiomeJsBundleTest.php
index 7634bec..b5ee51d 100644
--- a/tests/KocalBiomeJsBundleTest.php
+++ b/tests/KocalBiomeJsBundleTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace Kocal\BiomeJsBundle\Tests;
@@ -15,4 +16,4 @@ public function testContainerExtension(): void
 
         self::assertInstanceOf(BiomeJsExtension::class, $bundle->getContainerExtension());
     }
-}
\ No newline at end of file
+}
diff --git a/tests/fixtures/BiomeJsTestKernel.php b/tests/fixtures/BiomeJsTestKernel.php
index 71a3548..46656ff 100644
--- a/tests/fixtures/BiomeJsTestKernel.php
+++ b/tests/fixtures/BiomeJsTestKernel.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace Kocal\BiomeJsBundle\Tests\fixtures;
@@ -19,13 +20,12 @@ public function __construct()
         parent::__construct('test', true);
     }
 
-    public function registerBundles(): array
+    public function registerBundles(): iterable
     {
-        return [
-            new FrameworkBundle(),
-            new KocalBiomeJsBundle(),
-        ];
+        yield new FrameworkBundle();
+        yield new KocalBiomeJsBundle();
     }
+
     protected function configureContainer(ContainerBuilder $container, LoaderInterface $loader): void
     {
         $container->setParameter('biomejs.use_tty', false);
@@ -43,16 +43,16 @@ protected function configureContainer(ContainerBuilder $container, LoaderInterfa
 
     public function getCacheDir(): string
     {
-        return sys_get_temp_dir().'/cache'.spl_object_hash($this);
+        return sys_get_temp_dir() . '/cache' . spl_object_hash($this);
     }
 
     public function getLogDir(): string
     {
-        return sys_get_temp_dir().'/logs'.spl_object_hash($this);
+        return sys_get_temp_dir() . '/logs' . spl_object_hash($this);
     }
 
     public function getProjectDir(): string
     {
         return __DIR__;
     }
-}
\ No newline at end of file
+}