NodeEntityViewModeAlterTest.php

<?php

namespace Drupal\Tests\node\Functional;

use Drupal\Core\Cache\Cache;
use Drupal\Tests\EntityViewTrait;

/**
 * Tests changing view modes for nodes.
 *
 * @group node
 */
class NodeEntityViewModeAlterTest extends NodeTestBase {
    use EntityViewTrait;
    
    /**
     * Enable dummy module that implements hook_ENTITY_TYPE_view() for nodes.
     */
    protected static $modules = [
        'node_test',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * Create a "Basic page" node and verify its consistency in the database.
     */
    public function testNodeViewModeChange() {
        $web_user = $this->drupalCreateUser([
            'create page content',
            'edit own page content',
        ]);
        $this->drupalLogin($web_user);
        // Create a node.
        $edit = [];
        $edit['title[0][value]'] = $this->randomMachineName(8);
        $edit['body[0][value]'] = 'Data that should appear only in the body for the node.';
        $edit['body[0][summary]'] = 'Extra data that should appear only in the teaser for the node.';
        $this->drupalGet('node/add/page');
        $this->submitForm($edit, 'Save');
        $node = $this->drupalGetNodeByTitle($edit['title[0][value]']);
        // Set the flag to alter the view mode and view the node.
        \Drupal::state()->set('node_test_change_view_mode', 'teaser');
        Cache::invalidateTags([
            'rendered',
        ]);
        $this->drupalGet('node/' . $node->id());
        // Check that teaser mode is viewed.
        $this->assertSession()
            ->pageTextContains('Extra data that should appear only in the teaser for the node.');
        // Make sure body text is not present.
        $this->assertSession()
            ->pageTextNotContains('Data that should appear only in the body for the node.');
        // Test that the correct build mode has been set.
        $build = $this->buildEntityView($node);
        $this->assertEquals('teaser', $build['#view_mode'], 'The view mode has correctly been set to teaser.');
    }

}