fix(assets-controller): handle empty accounts on startup by listening to AccountTreeController state

Author: salimtb

eslint-suppressions.json

@@ -170,7 +170,7 @@
   },
   "packages/assets-controller/src/AssetsController.ts": {
     "no-restricted-syntax": {
-      "count": 7
+      "count": 8
     }
   },
   "packages/assets-controller/src/__fixtures__/MockAssetControllerMessenger.ts": {

packages/assets-controller/src/AssetsController.test.ts

@@ -1789,4 +1789,85 @@ describe('AssetsController', () => {
       });
     });
   });
+
+  describe('account tree state change', () => {
+    it('triggers start when tree initializes after unlock with empty accounts', async () => {
+      const getAccountsMock = jest.fn().mockReturnValue([]);
+
+      const messenger: RootMessenger = new Messenger({
+        namespace: MOCK_ANY_NAMESPACE,
+      });
+      messenger.registerActionHandler(
+        'AccountTreeController:getAccountsFromSelectedAccountGroup',
+        getAccountsMock,
+      );
+      messenger.registerActionHandler(
+        'NetworkEnablementController:getState',
+        () => ({
+          enabledNetworkMap: { eip155: { '1': true } },
+          nativeAssetIdentifiers: {
+            'eip155:1': 'eip155:1/slip44:60' as `${string}:${string}/slip44:${number}`,
+          },
+        }),
+      );
+      (
+        messenger as {
+          registerActionHandler: (a: string, h: () => unknown) => void;
+        }
+      ).registerActionHandler('NetworkController:getState', () => ({
+        networkConfigurationsByChainId: {},
+        networksMetadata: {},
+      }));
+      (
+        messenger as {
+          registerActionHandler: (a: string, h: () => unknown) => void;
+        }
+      ).registerActionHandler('NetworkController:getNetworkClientById', () => ({
+        provider: {},
+      }));
+      (
+        messenger as {
+          registerActionHandler: (a: string, h: () => unknown) => void;
+        }
+      ).registerActionHandler('ClientController:getState', () => ({
+        isUiOpen: true,
+      }));
+
+      const controller = new AssetsController({
+        messenger: messenger as unknown as AssetsControllerMessenger,
+        queryApiClient: createMockQueryApiClient(),
+        subscribeToBasicFunctionalityChange: (): void => {
+          /* no-op */
+        },
+      });
+
+      const getAssetsSpy = jest.spyOn(controller, 'getAssets');
+
+      // Step 1: UI open + unlock — accounts empty, #start() is a no-op
+      (
+        messenger as unknown as {
+          publish: (topic: string, payload?: unknown) => void;
+        }
+      ).publish('ClientController:stateChange', { isUiOpen: true });
+      messenger.publish('KeyringController:unlock');
+      await new Promise((resolve) => setTimeout(resolve, 100));
+
+      expect(getAssetsSpy).not.toHaveBeenCalled();
+
+      // Step 2: AccountTreeController.init() completes — accounts now available
+      getAccountsMock.mockReturnValue([createMockInternalAccount()]);
+      (messenger.publish as CallableFunction)(
+        'AccountTreeController:stateChange',
+        {},
+        [],
+      );
+      await new Promise((resolve) => setTimeout(resolve, 100));
+
+      expect(getAssetsSpy).toHaveBeenCalledTimes(1);
+      expect(getAssetsSpy).toHaveBeenCalledWith(
+        [expect.objectContaining({ id: MOCK_ACCOUNT_ID })],
+        expect.objectContaining({ forceUpdate: true }),
+      );
+    });
+  });
 });

packages/assets-controller/src/AssetsController.ts

@@ -1,6 +1,7 @@
 import type {
   AccountTreeControllerGetAccountsFromSelectedAccountGroupAction,
   AccountTreeControllerSelectedAccountGroupChangeEvent,
+  AccountTreeControllerStateChangeEvent,
 } from '@metamask/account-tree-controller';
 import { BaseController } from '@metamask/base-controller';
 import type {
@@ -282,6 +283,7 @@ type AllowedActions =
 type AllowedEvents =
   // AssetsController
   | AccountTreeControllerSelectedAccountGroupChangeEvent
+  | AccountTreeControllerStateChangeEvent
   | ClientControllerStateChangeEvent
   | KeyringControllerLockEvent
   | KeyringControllerUnlockEvent
@@ -865,6 +867,18 @@ export class AssetsController extends BaseController<
       },
     );
 
+    // Catch the initial tree build. On returning users,
+    // `selectedAccountGroupChange` does NOT fire when the persisted group
+    // is unchanged, and `accountTreeChange` doesn't fire either (init()
+    // rebuilds from persisted accounts without publishing it).
+    // The base-controller `:stateChange` event is guaranteed to fire
+    // when init() calls this.update(). #start() is idempotent so
+    // repeated fires are safe.
+    this.messenger.subscribe('AccountTreeController:stateChange', () => {
+      console.log('AccountTreeController:stateChanged +++++++++++');
+      this.#updateActive();
+    });
+
     // Subscribe to network enablement changes (only enabledNetworkMap)
     this.messenger.subscribe(
       'NetworkEnablementController:stateChange',
@@ -2047,18 +2061,30 @@ export class AssetsController extends BaseController<
 
   /**
    * Start asset tracking: subscribe to updates and fetch current balances.
-   * Called when app opens, account changes, or keyring unlocks.
+   * Idempotent — returns early if accounts/chains are not yet available or
+   * subscriptions are already active.
    */
   #start(): void {
+    const accounts = this.#selectedAccounts;
+    const chainIds = [...this.#enabledChains];
+
+    if (accounts.length === 0 || chainIds.length === 0) {
+      return;
+    }
+
+    if (this.#activeSubscriptions.size > 0) {
+      return;
+    }
+
     log('Starting asset tracking', {
-      selectedAccountCount: this.#selectedAccounts.length,
-      enabledChainCount: this.#enabledChains.size,
+      selectedAccountCount: accounts.length,
+      enabledChainCount: chainIds.length,
     });
 
     this.#subscribeAssets();
     this.#ensureNativeBalancesDefaultZero();
-    this.getAssets(this.#selectedAccounts, {
-      chainIds: [...this.#enabledChains],
+    this.getAssets(accounts, {
+      chainIds,
       forceUpdate: true,
     }).catch((error) => {
       log('Failed to fetch assets', error);