class MediaKernelTestBase

abstract class MediaKernelTestBase extends KernelTestBase {
    use MediaTypeCreationTrait;
    
    /**
     * Modules to install.
     *
     * @var array
     */
    protected static $modules = [
        'media',
        'media_test_source',
        'image',
        'user',
        'field',
        'system',
        'file',
    ];
    
    /**
     * The test media type.
     *
     * @var \Drupal\media\MediaTypeInterface
     */
    protected $testMediaType;
    
    /**
     * The test media type with constraints.
     *
     * @var \Drupal\media\MediaTypeInterface
     */
    protected $testConstraintsMediaType;
    
    /**
     * A user.
     *
     * @var \Drupal\user\UserInterface
     */
    protected $user;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() {
        parent::setUp();
        $this->installEntitySchema('user');
        $this->installEntitySchema('file');
        $this->installSchema('file', 'file_usage');
        $this->installSchema('system', 'sequences');
        $this->installEntitySchema('media');
        $this->installConfig([
            'field',
            'system',
            'image',
            'file',
            'media',
        ]);
        // Create a test media type.
        $this->testMediaType = $this->createMediaType('test');
        // Create a test media type with constraints.
        $this->testConstraintsMediaType = $this->createMediaType('test_constraints');
        $this->user = User::create([
            'name' => 'username',
            'status' => 1,
        ]);
        $this->user
            ->save();
        $this->container
            ->get('current_user')
            ->setAccount($this->user);
    }
    
    /**
     * Helper to generate a media item.
     *
     * @param string $filename
     *   String filename with extension.
     * @param \Drupal\media\MediaTypeInterface $media_type
     *   The media type.
     *
     * @return \Drupal\media\Entity\Media
     *   A media item.
     */
    protected function generateMedia($filename, MediaTypeInterface $media_type) {
        vfsStream::setup('drupal_root');
        vfsStream::create([
            'sites' => [
                'default' => [
                    'files' => [
                        $filename => str_repeat('a', 3000),
                    ],
                ],
            ],
        ]);
        $file = File::create([
            'uri' => 'vfs://drupal_root/sites/default/files/' . $filename,
            'uid' => $this->user
                ->id(),
        ]);
        $file->setPermanent();
        $file->save();
        return Media::create([
            'bundle' => $media_type->id(),
            'name' => 'Mr. Jones',
            'field_media_file' => [
                'target_id' => $file->id(),
            ],
        ]);
    }

}