我在WordPress中有自己的twig插件实现，我的翻译正在工作。你可以检查我的代码。

在测试代码时，请记住以下几点：

确保您的WordPress已设置locale 请确保您mo 文件是从最新版本的po 文件请确保mo 文件存在并由加载load_plugin_textdomain 函数您可以使用下面的脚本调试WordPress正在加载的翻译文件。

function wpse_287988_debug_mofiles( $mofile, $domain ) {

    var_dump($mofile);

    return $mofile;
}

add_filter( \'load_textdomain_mofile\', \'wpse_287988_debug_mofiles\', 10, 2);

function wpse_287988_terminate() {
    die();
}

add_filter( \'wp_loaded\', \'wpse_287988_terminate\' );

/**
 * Load composer autloader
 */
require_once dirname(__FILE__) . \'/vendor/autoload.php\';

// Main class

class WPSE_287988_Twig {

    /**
     * Templates path
     */
    private $templates_path;

    /**
     * Templates path
     */
    private $options;

    /**
     * Twig instance
     */
    private $twig;

    /**
     * Twig class constructor
     */
    public function __construct() {

        $this->templates_path = array();
        $this->options = array();

        $this->initialize_twig_options();
        $this->initialize_twig();
        $this->initialize_twig_functions();

        $this->define_hooks();
    }

    /**
     * Render method
     */
    public function render( $template, $variables = array() ) {

        return $this->twig->render( $template, $variables );
    }

    /**
     * Initialize twig options
     */
    private function initialize_twig_options() {

        /**
         * Resolve twig templates path
         */
        $plugins_dir = plugin_dir_path( __FILE__ );

        $this->templates_path[] = $plugins_dir;
        $this->templates_path[] = $plugins_dir . \'templates\';

        foreach ($this->templates_path as $path) {

            if ( ! file_exists($path) ) {
                mkdir($path);
            }
        }

        /**
         * Resolve twig env options, disable cache
         */
        $this->options[\'cache\'] = false;
    }

    /**
     * Initialize twig 
     */
    private function initialize_twig() {

        $loader       = new Twig_Loader_Filesystem( $this->templates_path );
        $this->twig   = new Twig_Environment($loader, $this->options );
    }

    /**
     * Initialize additional twig funcitons
     */
    public function initialize_twig_functions() {

        /**
         * Add gettext __ functions to twig functions.
         */
        $function = new Twig_Function(\'__\', \'__\');

        $this->twig->addFunction($function);
    }

    /**
     * Load the plugin translations
     */
    public function load_plugins_textdomain() {

        $textdomain = \'wpse_287988\';

        load_plugin_textdomain( $textdomain, false, basename( dirname( __FILE__ ) ) . \'/languages\' );
    }

    /**
     * Define hooks required by twig class
     */
    private function define_hooks()  {

        add_action( \'plugins_loaded\', array( $this, \'load_plugins_textdomain\' ) );
    }
}

// End of main class

// Initialize class

function wpse_287988_twig() {

    static $plugin;

    if ( isset( $plugin ) && $plugin instanceof WPSE_287988_Twig ) {
        return $plugin;
    }

    $plugin = new WPSE_287988_Twig();

    return $plugin;
}

wpse_287988_twig();

// End of class initialization

// Testing code

function wpse_287988_test_render() {

    $twig = wpse_287988_twig();
    echo $twig->render(\'template.html.twig\');

    die();
}

add_action(\'init\', \'wpse_287988_test_render\');

// End of testing code

{% set text = "Foo" %}

{{ __(text, \'wpse_287988\') }}