単一属性商品の WooCommerce バリエーション ドロップダウンで在庫状況を表示するにはどうすればよいですか?

<code class="php">add_filter( 'woocommerce_dropdown_variation_attribute_options_html', 'show_stock_status_in_dropdown', 10, 2);
function show_stock_status_in_dropdown( $html, $args ) {
    // Ensure there's only one variation attribute
    if( sizeof($args['product']->get_variation_attributes()) == 1 ) {
        $options = $args['options'];
        $product = $args['product'];
        $attribute = $args['attribute'];
        $name = $args['name'] ? $args['name'] : 'attribute_' . sanitize_title( $attribute );
        $show_option_none = $args['show_option_none'] ? true : false;

        if ( ! empty( $options ) ) {
            $html = '<select id="' . esc_attr( $id ) . '" class="' . esc_attr( $class ) . '" name="' . esc_attr( $name ) . '" data-attribute_name="attribute_' . esc_attr( sanitize_title( $attribute ) ) . '" data-show_option_none="' . ( $show_option_none ? 'yes' : 'no' ) . '">';
            $html .= '<option value="">' . esc_html( $show_option_none_text ) . '</option>';

            foreach ( $options as $option ) {
                $stock_status = get_stock_status_text( $product, $name, $option );
                $html .= '<option value="' . esc_attr( $option ) . '" ' . selected( sanitize_title( $args['selected'] ), $option, false ) . '>' . esc_html( apply_filters( 'woocommerce_variation_option_name', $option ) . $stock_status ) . '</option>';
            }
            $html .= '</select>';
        }
    }
    return $html;
}</code>

<code class="php">function get_stock_status_text( $product, $name, $term_slug ) {
    foreach ( $product->get_available_variations() as $variation ){
        if($variation['attributes'][$name] == $term_slug ) {
            $stock = $variation['is_in_stock'];
            break;
        }
    }
    return $stock == 1 ? ' - (In Stock)' : ' - (Out of Stock)';
}</code>