e ) ] );
				}
			} elseif ( is_shop() && $shop_page === $menu_id && 'page' === $menu_item->object ) {
				// Set active state if this is the shop page link.
				$menu_items[ $key ]->current = true;
				$classes[]                   = 'current-menu-item';
				$classes[]                   = 'current_page_item';

			} elseif ( is_singular( 'product' ) && $shop_page === $menu_id ) {
				// Set parent state if this is a product page.
				$classes[] = 'current_page_parent';
			}

			$menu_items[ $key ]->classes = array_unique( $classes );
		}
	}

	return $menu_items;
}
add_filter( 'wp_nav_menu_objects', 'wc_nav_menu_item_classes', 2 );


/**
 * Fix active class in wp_list_pages for shop page.
 *
 * See details in https://github.com/woocommerce/woocommerce/issues/177.
 *
 * @param string $pages Pages list.
 * @return string
 */
function wc_list_pages( $pages ) {
	if ( ! is_woocommerce() ) {
		return $pages;
	}

	// Remove current_page_parent class from any item.
	$pages = str_replace( 'current_page_parent', '', $pages );
	// Find shop_page_id through woocommerce options.
	$shop_page = 'page-item-' . wc_get_page_id( 'shop' );

	if ( is_shop() ) {
		// Add current_page_item class to shop page.
		return str_replace( $shop_page, $shop_page . ' current_page_item', $pages );
	}

	// Add current_page_parent class to shop page.
	return str_replace( $shop_page, $shop_page . ' current_page_parent', $pages );
}
add_filter( 'wp_list_pages', 'wc_list_pages' );