Code-Snippets-Functions/Execute a function on a child site/WooCommerce/display-regular-price-before-sales-price-in-cart.txt

add_filter( 'woocommerce_cart_total', 'custom_cart_total_html', 10, 2 );

function custom_cart_total_html( $total_html, $cart ) {
    $regular_price_total = 0;
    foreach ( $cart->get_cart() as $cart_item_key => $cart_item ) {
        $product = $cart_item['data'];
        if ( $product->is_on_sale() ) {
            $regular_price = wc_get_price_to_display( $product, array( 'price' => $product->get_regular_price() ) );
            $regular_price_total += $regular_price * $cart_item['quantity'];
        }
    }
    if ( $regular_price_total > 0 ) {
        $total_html = '<del>' . wc_price( $regular_price_total ) . '</del> ' . $total_html;
    }
    return $total_html;
}