class BookUninstallTest

class BookUninstallTest extends KernelTestBase {
    
    /**
     * Modules to enable.
     *
     * @var array
     */
    protected static $modules = [
        'system',
        'user',
        'field',
        'filter',
        'text',
        'node',
        'book',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        parent::setUp();
        $this->installEntitySchema('user');
        $this->installEntitySchema('node');
        $this->installSchema('book', [
            'book',
        ]);
        $this->installSchema('node', [
            'node_access',
        ]);
        $this->installConfig([
            'node',
            'book',
            'field',
        ]);
        // For uninstall to work.
        $this->installSchema('user', [
            'users_data',
        ]);
    }
    
    /**
     * Tests the book_system_info_alter() method.
     */
    public function testBookUninstall() {
        // No nodes exist.
        $validation_reasons = \Drupal::service('module_installer')->validateUninstall([
            'book',
        ]);
        $this->assertEquals([], $validation_reasons, 'The book module is not required.');
        $content_type = NodeType::create([
            'type' => $this->randomMachineName(),
            'name' => $this->randomString(),
        ]);
        $content_type->save();
        $book_config = $this->config('book.settings');
        $allowed_types = $book_config->get('allowed_types');
        $allowed_types[] = $content_type->id();
        $book_config->set('allowed_types', $allowed_types)
            ->save();
        $node = Node::create([
            'title' => $this->randomString(),
            'type' => $content_type->id(),
        ]);
        $node->book['bid'] = 'new';
        $node->save();
        // One node in a book but not of type book.
        $validation_reasons = \Drupal::service('module_installer')->validateUninstall([
            'book',
        ]);
        $this->assertEquals([
            'To uninstall Book, delete all content that is part of a book',
        ], $validation_reasons['book']);
        $book_node = Node::create([
            'title' => $this->randomString(),
            'type' => 'book',
        ]);
        $book_node->book['bid'] = FALSE;
        $book_node->save();
        // Two nodes, one in a book but not of type book and one book node (which is
        // not in a book).
        $validation_reasons = \Drupal::service('module_installer')->validateUninstall([
            'book',
        ]);
        $this->assertEquals([
            'To uninstall Book, delete all content that is part of a book',
        ], $validation_reasons['book']);
        $node->delete();
        // One node of type book but not actually part of a book.
        $validation_reasons = \Drupal::service('module_installer')->validateUninstall([
            'book',
        ]);
        $this->assertEquals([
            'To uninstall Book, delete all content that has the Book content type',
        ], $validation_reasons['book']);
        $book_node->delete();
        // No nodes exist therefore the book module is not required.
        $module_data = \Drupal::service('extension.list.module')->getList();
        $this->assertFalse(isset($module_data['book']->info['required']), 'The book module is not required.');
        $node = Node::create([
            'title' => $this->randomString(),
            'type' => $content_type->id(),
        ]);
        $node->save();
        // One node exists but is not part of a book therefore the book module is
        // not required.
        $validation_reasons = \Drupal::service('module_installer')->validateUninstall([
            'book',
        ]);
        $this->assertEquals([], $validation_reasons, 'The book module is not required.');
        // Uninstall the Book module and check the node type is deleted.
        \Drupal::service('module_installer')->uninstall([
            'book',
        ]);
        $this->assertNull(NodeType::load('book'), "The book node type does not exist.");
    }

}