getTotalDiscountDiffSum example

/** @var AbsolutePriceDefinition|null $priceDefinition */
        $priceDefinition = $discount->getPriceDefinition();

        if (!$priceDefinition instanceof AbsolutePriceDefinition) {
            throw new InvalidPriceDefinitionException($discount->getLabel(), $discount->getCode());
        }

        $fixedTotalPrice = abs($priceDefinition->getPrice());

        $affectedPrices = $packages->getAffectedPrices();

        $discountDiff = $this->getTotalDiscountDiffSum($fixedTotalPrice, $packages, $affectedPrices);

        // now calculate the correct price         // from our collected total discount price         $discountPrice = $this->absolutePriceCalculator->calculate(
            -abs($discountDiff),
            $affectedPrices,
            $context
        );

        $composition = $this->getCompositionItems(
            $discountPrice->getTotalPrice(),