MDVA-31363 Magento patch: Cart price rule does not apply (GraphQL)

A new patch called MDVA-33975 fixes GraphQL price calculation issues. MDVA-31363 is depreciated and it is recommended that you apply the patch MDVA-33975. To access this patch, refer to MDVA-33975 Magento patch: GraphQL price calculations.

The MDVA-31363 Magento patch fixes the issue where the cart price rule with coupon does not apply via GraphQL when the 'Fixed amount discount for whole cart' action is used. This patch is available when the Magento Quality Patch (MQP) tool 1.0.9 is installed. The issue is scheduled to be fixed in Magento version 2.4.2.

Affected products and versions

The patch is created for Magento version:
Magento Commerce Cloud 2.4.0

Compatible with Magento versions:
Magento Commerce and Magento Commerce Cloud 2.3.2-2.4.1

Note: the patch might become applicable to other versions with new MQP tool releases. To check if the patch is compatible with your Magento version, run ./vendor/bin/magento-patches status.

Issue 

Recalculating quote totals before giving a response about quote prices causes applied rules to be lost.

Steps to reproduce

1. Create a simple product. 
2. Create a cart price rule with a fixed amount discount for the whole cart. 
3. Create a new shopping cart using GraphQL.
4. Save the card_id from the response and add the product from step 1 to the cart using GraphQL.
5. Activate the cart price rule by adding the coupon code to cart using GraphQL.
6. Check price in response.

Actual result:

Discount is not applied.

Expected result:
Discount is applied.

Apply the patch

For instructions on how to apply an MQP patch, use the following links depending on your Magento product:

• Magento Commerce: DevDocs Apply patches using Magento Quality Patches Tool.
• Magento Commerce Cloud: DevDocs Upgrades and Patches > Apply patches.

Related reading

To learn more about Magento Quality Patches, refer to:

•  Magento Quality Patches released: a new tool to self-serve quality patches.
•  Check if patch is available for your Magento issue using Magento Quality Patches.

For info about other patches available in MQP tool, refer to the Patches available in MQP tool section.