class TaxonomyRelationshipTest

class TaxonomyRelationshipTest extends TaxonomyTestBase {
    
    /**
     * Stores the terms used in the tests.
     *
     * @var \Drupal\taxonomy\TermInterface[]
     */
    protected $terms = [];
    
    /**
     * Views used by this test.
     *
     * @var array
     */
    public static $testViews = [
        'test_taxonomy_term_relationship',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * {@inheritdoc}
     */
    protected function setUp($import_test_views = TRUE, $modules = []) : void {
        parent::setUp($import_test_views, $modules);
        // Make term2 parent of term1.
        $this->term1
            ->set('parent', $this->term2
            ->id());
        $this->term1
            ->save();
        // Store terms in an array for testing.
        $this->terms[] = $this->term1;
        $this->terms[] = $this->term2;
        // Only set term1 on node1 and term2 on node2 for testing.
        unset($this->nodes[0]->field_views_testing_tags[1]);
        $this->nodes[0]
            ->save();
        unset($this->nodes[1]->field_views_testing_tags[0]);
        $this->nodes[1]
            ->save();
        Views::viewsData()->clear();
    }
    
    /**
     * Tests the taxonomy parent plugin UI.
     */
    public function testTaxonomyRelationships() : void {
        // Check the generated views data of taxonomy_index.
        $views_data = Views::viewsData()->get('taxonomy_index');
        // Check the table join data.
        $this->assertEquals('tid', $views_data['table']['join']['taxonomy_term_field_data']['left_field']);
        $this->assertEquals('tid', $views_data['table']['join']['taxonomy_term_field_data']['field']);
        $this->assertEquals('nid', $views_data['table']['join']['node_field_data']['left_field']);
        $this->assertEquals('nid', $views_data['table']['join']['node_field_data']['field']);
        $this->assertEquals('entity_id', $views_data['table']['join']['taxonomy_term__parent']['left_field']);
        $this->assertEquals('tid', $views_data['table']['join']['taxonomy_term__parent']['field']);
        // Check the generated views data of taxonomy_term__parent.
        $views_data = Views::viewsData()->get('taxonomy_term__parent');
        // Check the table join data.
        $this->assertEquals('entity_id', $views_data['table']['join']['taxonomy_term__parent']['left_field']);
        $this->assertEquals('parent_target_id', $views_data['table']['join']['taxonomy_term__parent']['field']);
        $this->assertEquals('tid', $views_data['table']['join']['taxonomy_term_field_data']['left_field']);
        $this->assertEquals('entity_id', $views_data['table']['join']['taxonomy_term_field_data']['field']);
        // Check the parent relationship data.
        $this->assertEquals('taxonomy_term_field_data', $views_data['parent_target_id']['relationship']['base']);
        $this->assertEquals('tid', $views_data['parent_target_id']['relationship']['base field']);
        $this->assertEquals('Parent', $views_data['parent_target_id']['relationship']['label']);
        $this->assertEquals('standard', $views_data['parent_target_id']['relationship']['id']);
        // Check the parent filter and argument data.
        $this->assertEquals('numeric', $views_data['parent_target_id']['filter']['id']);
        $this->assertEquals('taxonomy', $views_data['parent_target_id']['argument']['id']);
        // Check an actual test view.
        $view = Views::getView('test_taxonomy_term_relationship');
        $this->executeView($view);
        
        /** @var \Drupal\views\ResultRow $row */
        foreach ($view->result as $index => $row) {
            // Check that the actual ID of the entity is the expected one.
            $this->assertEquals($this->terms[$index]
                ->id(), $row->tid);
            // Also check that we have the correct result entity.
            $this->assertEquals($this->terms[$index]
                ->id(), $row->_entity
                ->id());
            $this->assertInstanceOf(TermInterface::class, $row->_entity);
            if (!$index) {
                $this->assertInstanceOf(TermInterface::class, $row->_relationship_entities['parent']);
                $this->assertEquals($this->term2
                    ->id(), $row->_relationship_entities['parent']
                    ->id());
                $this->assertEquals($this->term2
                    ->id(), $row->taxonomy_term_field_data_taxonomy_term__parent_tid);
            }
            $this->assertInstanceOf(NodeInterface::class, $row->_relationship_entities['nid']);
            $this->assertEquals($this->nodes[$index]
                ->id(), $row->_relationship_entities['nid']
                ->id());
        }
        // Test node fields are available through relationship.
        \Drupal::service('module_installer')->install([
            'views_ui',
        ]);
        $this->drupalLogin($this->createUser([
            'administer views',
        ]));
        $this->drupalGet('admin/structure/views/view/test_taxonomy_term_relationship');
        $this->click('#views-add-field');
        $this->assertSession()
            ->pageTextContains('Body');
    }

}