Add WooCommerce cart link to primary menu when cart is not empty

functions.php

<?php

/*
*
*  Wordpress and WooCommerce
*  Add a "Cart" link to the menu when the cart is not empty
*
*  When a customer adds an item to their woocommerce cart, a cart
*  link will be added to the primary menu.
*
*/

add_filter( 'wp_nav_menu_items', 'pilgrim_add_cart_link', 10, 2 );

function pilgrim_add_cart_link( $items, $args ) {
   if ($args->theme_location == 'primary') {
      if (sizeof(WC()->cart->get_cart()) != 0) {
         $items .= '<li><a href="/cart/">My Cart</a></li>';
      }
   }
   return $items;
}