Use correct key for 'quantity' in add-item API call (#3875)

* Use correct key for 'quantity' in add-item API call

* Add changelog and readme entries

Author: annemirasol

changelog.txt

@@ -1,6 +1,7 @@
 *** Changelog ***
 
 = 9.2.0 - xxxx-xx-xx =
+* Fix - Fix the quantity parameter for the express checkout add-to-cart API call.
 * Dev - Replaces part of the StoreAPI call code for the cart endpoints to use the newly introduced filter.
 * Fix - Clear cart first when using express checkout inside the product page.
 * Fix - Avoid Stripe timeouts for the express checkout click event.

client/api/index.js

@@ -524,9 +524,17 @@ export default class WCStripeAPI {
 	 * @return {Promise} Promise for the request to the server.
 	 */
 	expressCheckoutAddToCart( productData ) {
+		// Rename qty to quantity to match StoreAPI expected parameter.
+		const { qty, ...rest } = productData;
+		const quantity = qty ?? 1;
+		const blocksApiProductData = {
+			...rest,
+			quantity,
+		};
+
 		const data = applyFilters(
 			'wcstripe.express-checkout.cart-add-item',
-			productData
+			blocksApiProductData
 		);
 		return this.postToBlocksAPI( '/wc/store/v1/cart/add-item', data );
 	}

readme.txt

@@ -111,6 +111,7 @@ If you get stuck, you can ask for help in the [Plugin Forum](https://wordpress.o
 == Changelog ==
 
 = 9.2.0 - xxxx-xx-xx =
+* Fix - Fix the quantity parameter for the express checkout add-to-cart API call.
 * Dev - Replaces part of the StoreAPI call code for the cart endpoints to use the newly introduced filter.
 * Fix - Clear cart first when using express checkout inside the product page.
 * Fix - Avoid Stripe timeouts for the express checkout click event.