protected function set_coupon_discount_amounts( $discounts ) {
		$coupons           = $this->get_items( 'coupon' );
		$coupon_code_to_id = wc_list_pluck( $coupons, 'get_id', 'get_code' );
		$all_discounts     = $discounts->get_discounts();
		$coupon_discounts  = $discounts->get_discounts_by_coupon();

		if ( $coupon_discounts ) {
			foreach ( $coupon_discounts as $coupon_code => $amount ) {
				$item_id = isset( $coupon_code_to_id[ $coupon_code ] ) ? $coupon_code_to_id[ $coupon_code ] : 0;

				if ( ! $item_id ) {
					$coupon_item = new WC_Order_Item_Coupon();
					$coupon_item->set_code( $coupon_code );
				} else {
					$coupon_item = $this->get_item( $item_id, false );
				}

				$discount_tax = 0;

				// Work out how much tax has been removed as a result of the discount from this coupon.
				foreach ( $all_discounts[ $coupon_code ] as $item_id => $item_discount_amount ) {
					$item = $this->get_item( $item_id, false );

					if ( 'taxable' !== $item->get_tax_status() || ! wc_tax_enabled() ) {
						continue;
					}

					$taxes = array_sum( WC_Tax::calc_tax( $item_discount_amount, WC_Tax::get_rates( $item->get_tax_class() ), $this->get_prices_include_tax() ) );
					if ( 'yes' !== get_option( 'woocommerce_tax_round_at_subtotal' ) ) {
						$taxes = wc_round_tax_total( $taxes );
					}

					$discount_tax += $taxes;

					if ( $this->get_prices_include_tax() ) {
						$amount = $amount - $taxes;
					}
				}

				$coupon_item->set_discount( $amount );
				$coupon_item->set_discount_tax( $discount_tax );

				$this->add_item( $coupon_item );
			}
		}
	}