TwigExtensionTestController.php

<?php

namespace Drupal\twig_extension_test;

use Drupal\Core\StringTranslation\StringTranslationTrait;

/**
 * Controller routines for Twig extension test routes.
 */
class TwigExtensionTestController {
    use StringTranslationTrait;
    
    /**
     * Menu callback for testing Twig filters in a Twig template.
     */
    public function testFilterRender() {
        return [
            '#theme' => 'twig_extension_test_filter',
            '#message' => 'Every animal is not a mineral.',
            '#safe_join_items' => [
                '<em>will be escaped</em>',
                $this->t('<em>will be markup</em>'),
                [
                    '#markup' => '<strong>will be rendered</strong>',
                ],
            ],
        ];
    }
    
    /**
     * Menu callback for testing Twig functions in a Twig template.
     */
    public function testFunctionRender() {
        return [
            '#theme' => 'twig_extension_test_function',
        ];
    }

}