feat: add rewardAccountId to GetSubscriptionsResponse data (#7319)

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Subscription controller add `rewardAccountId` property to
`GetSubscriptionsResponse`

## References

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## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs)
- [x] I've introduced [breaking
changes](https://github.com/MetaMask/core/tree/main/docs/breaking-changes.md)
in this PR and have prepared draft pull requests for clients and
consumer packages to resolve them

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds `rewardAccountId` to `GetSubscriptionsResponse` and controller
state, updating `getSubscriptions` logic and tests.
> 
> - **Types**:
> - Extend `GetSubscriptionsResponse` with `rewardAccountId` and
propagate CAIP account type.
> - **Controller**:
> - Add `rewardAccountId` to `SubscriptionControllerState` and state
metadata.
> - Update `getSubscriptions` to read, compare, and persist
`rewardAccountId` alongside existing fields.
> - **Tests**:
> - Add tests verifying state update when `rewardAccountId` changes and
no-op when unchanged.
> - **Docs**:
>   - Update `CHANGELOG.md` to note inclusion of `rewardAccountId`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
8db5494. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: tuna1207

packages/subscription-controller/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- Updated `GetSubscriptionsResponse` and controller state to include `rewardAccountId` property ([#7319](https://github.com/MetaMask/core/pull/7319))
+
 ## [5.3.1]
 
 ### Changed

packages/subscription-controller/src/SubscriptionController.test.ts

@@ -594,6 +594,66 @@ describe('SubscriptionController', () => {
         },
       );
     });
+
+    it('should update state when rewardAccountId changes from undefined to defined', async () => {
+      await withController(
+        {
+          state: {
+            rewardAccountId: undefined,
+          },
+        },
+        async ({ controller, mockService }) => {
+          mockService.getSubscriptions.mockResolvedValue({
+            customerId: 'cus_1',
+            subscriptions: [],
+            trialedProducts: [],
+            rewardAccountId:
+              'eip155:1:0x1234567890123456789012345678901234567890',
+          });
+
+          await controller.getSubscriptions();
+
+          expect(controller.state.rewardAccountId).toBe(
+            'eip155:1:0x1234567890123456789012345678901234567890',
+          );
+        },
+      );
+    });
+
+    it('should not update state when rewardAccountId is the same', async () => {
+      const mockRewardAccountId =
+        'eip155:1:0x1234567890123456789012345678901234567890';
+
+      await withController(
+        {
+          state: {
+            customerId: 'cus_1',
+            subscriptions: [],
+            trialedProducts: [],
+            rewardAccountId: mockRewardAccountId,
+          },
+        },
+        async ({ controller, mockService, rootMessenger }) => {
+          mockService.getSubscriptions.mockResolvedValue({
+            customerId: 'cus_1',
+            subscriptions: [],
+            trialedProducts: [],
+            rewardAccountId: mockRewardAccountId,
+          });
+
+          const stateChangeListener = jest.fn();
+          rootMessenger.subscribe(
+            'SubscriptionController:stateChange',
+            stateChangeListener,
+          );
+
+          await controller.getSubscriptions();
+
+          // State should not have changed since rewardAccountId is the same
+          expect(stateChangeListener).not.toHaveBeenCalled();
+        },
+      );
+    });
   });
 
   describe('getSubscriptionByProduct', () => {

packages/subscription-controller/src/SubscriptionController.ts

@@ -52,6 +52,8 @@ export type SubscriptionControllerState = {
   pricing?: PricingResponse;
   /** The last subscription that user has subscribed to if any. */
   lastSubscription?: Subscription;
+  /** The reward account ID if user has linked rewards to the subscription. */
+  rewardAccountId?: CaipAccountId;
   /**
    * The last selected payment method for the user.
    * This is used to display the last selected payment method in the UI.
@@ -221,6 +223,12 @@ const subscriptionControllerMetadata: StateMetadata<SubscriptionControllerState>
       includeInDebugSnapshot: false,
       usedInUi: true,
     },
+    rewardAccountId: {
+      includeInStateLogs: true,
+      persist: true,
+      includeInDebugSnapshot: false,
+      usedInUi: true,
+    },
     trialedProducts: {
       includeInStateLogs: true,
       persist: true,
@@ -362,11 +370,14 @@ export class SubscriptionController extends StaticIntervalPollingController()<
     const currentTrialedProducts = this.state.trialedProducts;
     const currentCustomerId = this.state.customerId;
     const currentLastSubscription = this.state.lastSubscription;
+    const currentRewardAccountId = this.state.rewardAccountId;
+
     const {
       customerId: newCustomerId,
       subscriptions: newSubscriptions,
       trialedProducts: newTrialedProducts,
       lastSubscription: newLastSubscription,
+      rewardAccountId: newRewardAccountId,
     } = await this.#subscriptionService.getSubscriptions();
 
     // check if the new subscriptions are different from the current subscriptions
@@ -386,20 +397,23 @@ export class SubscriptionController extends StaticIntervalPollingController()<
     );
 
     const areCustomerIdsEqual = currentCustomerId === newCustomerId;
-
+    const areRewardAccountIdsEqual =
+      currentRewardAccountId === newRewardAccountId;
     // only update the state if the subscriptions or trialed products are different
     // this prevents unnecessary state updates events, easier for the clients to handle
     if (
       !areSubscriptionsEqual ||
       !isLastSubscriptionEqual ||
       !areTrialedProductsEqual ||
-      !areCustomerIdsEqual
+      !areCustomerIdsEqual ||
+      !areRewardAccountIdsEqual
     ) {
       this.update((state) => {
         state.subscriptions = newSubscriptions;
         state.customerId = newCustomerId;
         state.trialedProducts = newTrialedProducts;
         state.lastSubscription = newLastSubscription;
+        state.rewardAccountId = newRewardAccountId;
       });
       // trigger access token refresh to ensure the user has the latest access token if subscription state change
       this.triggerAccessTokenRefresh();

packages/subscription-controller/src/types.ts

@@ -125,6 +125,8 @@ export type GetSubscriptionsResponse = {
   trialedProducts: ProductType[];
   /** The last subscription that user has subscribed to if any. */
   lastSubscription?: Subscription;
+  /** The reward account ID if user has linked rewards to the subscription. */
+  rewardAccountId?: CaipAccountId;
 };
 
 export type StartSubscriptionRequest = {