How to display discount in OpenCart 2.3 cart?

Question

opencart

Hey! Such a question, how can you display a variable $specialin the basket, so that, provided that the product has a discount, the price is displayed in the same way as in the product card. In general, so that the goods in the basket have the old and new prices.
Tried to add the following in cart.php controller:
'special' => $special,
But it doesn't work.

Answer 1

'special' => $special

Well, it's understandable why it doesn't work.
In general, with a basket, everything is not so simple. It uses the price already taking into account the selected options, discounts, etc. and it is considered in system/library/cart, and not taken directly from the database