feat: add a canSync check for account syncing (#4690)

## Explanation

This PR ensures we don't fire account syncing if the conditions are not
entirely met.

## References

## Changelog

### `@metamask/profile-sync-controller`

- **ADDED**: Add a `canSync` check to account syncing

## 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 highlighted breaking changes using the "BREAKING" category
above as appropriate

packages/profile-sync-controller/src/controllers/user-storage/UserStorageController.test.ts

@@ -388,7 +388,7 @@ describe('user-storage/user-storage-controller - enableProfileSyncing() tests',
 });
 
 describe('user-storage/user-storage-controller - syncInternalAccountsWithUserStorage() tests', () => {
-  it('rejects if UserStorage is not enabled', async () => {
+  it('returns void if UserStorage is not enabled', async () => {
     const arrangeMocks = async () => {
       return {
         messengerMocks: mockUserStorageMessenger(),
@@ -409,9 +409,9 @@ describe('user-storage/user-storage-controller - syncInternalAccountsWithUserSto
       },
     });
 
-    await expect(
-      controller.syncInternalAccountsWithUserStorage(),
-    ).rejects.toThrow(expect.any(Error));
+    await controller.syncInternalAccountsWithUserStorage();
+
+    expect(messengerMocks.mockAccountsListAccounts).not.toHaveBeenCalled();
   });
 
   it('returns void if account syncing feature flag is disabled', async () => {
@@ -1083,7 +1083,7 @@ describe('user-storage/user-storage-controller - syncInternalAccountsWithUserSto
 });
 
 describe('user-storage/user-storage-controller - saveInternalAccountToUserStorage() tests', () => {
-  it('rejects if UserStorage is not enabled', async () => {
+  it('returns void if UserStorage is not enabled', async () => {
     const arrangeMocks = async () => {
       return {
         messengerMocks: mockUserStorageMessenger(),
@@ -1103,11 +1103,13 @@ describe('user-storage/user-storage-controller - saveInternalAccountToUserStorag
       },
     });
 
-    await expect(
-      controller.saveInternalAccountToUserStorage(
-        MOCK_INTERNAL_ACCOUNTS.ONE[0].address,
-      ),
-    ).rejects.toThrow(expect.any(Error));
+    await controller.saveInternalAccountToUserStorage(
+      MOCK_INTERNAL_ACCOUNTS.ONE[0].address,
+    );
+
+    expect(
+      messengerMocks.mockAccountsGetAccountByAddress,
+    ).not.toHaveBeenCalled();
   });
 
   it('returns void if account syncing feature flag is disabled', async () => {

packages/profile-sync-controller/src/controllers/user-storage/UserStorageController.ts

@@ -266,6 +266,17 @@ export default class UserStorageController extends BaseController<
     // We will remove this once the feature will be released
     isAccountSyncingEnabled: false,
     isAccountSyncingInProgress: false,
+    canSync: () => {
+      try {
+        this.#assertProfileSyncingEnabled();
+
+        return (
+          this.#accounts.isAccountSyncingEnabled && this.#auth.isAuthEnabled()
+        );
+      } catch {
+        return false;
+      }
+    },
     setupAccountSyncingSubscriptions: () => {
       this.messagingSystem.subscribe(
         'AccountsController:accountAdded',
@@ -718,13 +729,11 @@ export default class UserStorageController extends BaseController<
    * It will add new accounts to the internal accounts list, update/merge conflicting names and re-upload the results in some cases to the user storage.
    */
   async syncInternalAccountsWithUserStorage(): Promise<void> {
-    if (!this.#accounts.isAccountSyncingEnabled) {
+    if (!this.#accounts.canSync()) {
       return;
     }
 
     try {
-      this.#assertProfileSyncingEnabled();
-
       this.#accounts.isAccountSyncingInProgress = true;
 
       const userStorageAccountsList =
@@ -858,7 +867,7 @@ export default class UserStorageController extends BaseController<
    * @param address - The address of the internal account to save
    */
   async saveInternalAccountToUserStorage(address: string): Promise<void> {
-    if (!this.#accounts.isAccountSyncingEnabled) {
+    if (!this.#accounts.canSync()) {
       return;
     }