StringLoader.php

<?php

namespace Drupal\Core\Template\Loader;

use Twig\Loader\LoaderInterface;
use Twig\Source;

/**
 * Loads string templates, also known as inline templates.
 *
 * This loader is intended to be used in a Twig loader chain and only loads
 * string templates that begin with the following comment:
 * @code
 * {# inline_template_start #}
 * @endcode
 *
 * This class override ensures that the string loader behaves as expected in
 * the loader chain. If Twig's string loader is used as is, any string (even a
 * reference to a file-based Twig template) is treated as a valid template and
 * is rendered instead of a \Twig\Error\LoaderError exception being thrown.
 *
 * @see \Drupal\Core\Template\TwigEnvironment::renderInline()
 * @see \Drupal\Core\Render\Element\InlineTemplate
 * @see twig_render_template()
 */
class StringLoader implements LoaderInterface {
    
    /**
     * {@inheritdoc}
     */
    public function exists($name) {
        if (str_starts_with($name, '{# inline_template_start #}')) {
            return TRUE;
        }
        else {
            return FALSE;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCacheKey(string $name) : string {
        return $name;
    }
    
    /**
     * {@inheritdoc}
     */
    public function isFresh(string $name, int $time) : bool {
        return TRUE;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getSourceContext(string $name) : Source {
        $name = (string) $name;
        return new Source($name, $name);
    }

}