fix: keep shared folders from other servers when they reuse an account id #1108

lib/__tests__/unified-mailbox-dedupe.test.ts

@@ -54,4 +54,24 @@ describe('dedupeUnifiedAccounts', () => {
     const group = sharedEntry('G', 'login-a', [mb('G:inbox', 'inbox', 1, 'inbox')]);
     expect(dedupeUnifiedAccounts([a, b, group])).toEqual([a, b, group]);
   });
+  it('does not merge equal JMAP ids that live on different servers', () => {
+    // Stalwart hands out the same short account and mailbox ids on every
+    // server, so login A's own folder and a folder shared to login B on
+    // another server can both be account "c", mailbox "f1".
+    const server = (url: string) => ({ getServerUrl: () => url } as unknown as IJMAPClient);
+    const own = makeAccount({ accountId: 'login-a', jmapAccountId: 'c', client: server('https://one.example'), mailboxes: [mb('f1', undefined, 1)] });
+    const sharedElsewhere = sharedEntry('c', 'login-b', [mb('c:f1', undefined, 2, 'f1')]);
+    sharedElsewhere.client = server('https://two.example');
+    const out = dedupeUnifiedAccounts([own, sharedElsewhere]);
+    expect(out).toEqual([own, sharedElsewhere]);
+    expect(getCrossUnreadTotal(out)).toBe(3);
+  });
+
+  it('still merges the same folder reached through two logins of one server', () => {
+    const server = (url: string) => ({ getServerUrl: () => url } as unknown as IJMAPClient);
+    const own = makeAccount({ accountId: 'login-a', jmapAccountId: 'c', client: server('https://one.example'), mailboxes: [mb('f1', undefined, 1)] });
+    const viaGrantee = sharedEntry('c', 'login-b', [mb('c:f1', undefined, 1, 'f1')]);
+    viaGrantee.client = server('https://ONE.example/');
+    expect(dedupeUnifiedAccounts([viaGrantee, own])).toEqual([own]);
+  });
 });

lib/unified-mailbox.ts

@@ -768,6 +768,11 @@ export function connectedAccountsGrew(previous: string | null, current: string):
   return current.split(',').some((id) => id !== '' && !before.has(id));
 }
 
+/** The server a client talks to, compared without case or a trailing slash. */
+export function unifiedServerKey(client: Pick<IJMAPClient, 'getServerUrl'> | undefined): string {
+  return (client?.getServerUrl?.() ?? '').trim().replace(/\/+$/, '').toLowerCase();
+}
+
 /**
  * How far the unified scope has got while logins are still reconnecting:
  * `{ loaded, total }` while some logins expected in it are not there yet,
@@ -795,18 +800,22 @@ export function unifiedLoadProgress(input: {
  * shared with two logins at once, otherwise yields one entry per reaching
  * login: its messages list twice and its unread count is summed twice.
  *
- * A mailbox is identified by its owning JMAP account + server-side id (a shared
- * entry's `originalId`). Personal entries always win and are never trimmed, so
+ * A mailbox is identified by its server, its owning JMAP account and its
+ * server-side id (a shared entry's `originalId`). JMAP account and mailbox ids
+ * are only unique on one server (Stalwart hands out short ids like "b" or "c"
+ * everywhere), so logins on different servers never cover each other's
+ * folders. Personal entries always win and are never trimmed, so
  * an owner's folder is read through the owner's own login and honors their
  * folder selection. Shared entries keep only mailboxes not already covered and
  * are dropped when none remain. Order is preserved.
  */
 export function dedupeUnifiedAccounts(accounts: UnifiedAccountClient[]): UnifiedAccountClient[] {
   const seen = new Set<string>();
-  const key = (jmapAccountId: string, mailboxId: string) => `${jmapAccountId}\u0000${mailboxId}`;
+  const key = (account: UnifiedAccountClient, mailboxId: string) =>
+    `${unifiedServerKey(account.client)}\u0000${account.jmapAccountId}\u0000${mailboxId}`;
   for (const account of accounts) {
     if (account.isShared) continue;
-    for (const m of account.mailboxes) seen.add(key(account.jmapAccountId, m.id));
+    for (const m of account.mailboxes) seen.add(key(account, m.id));
   }
   const out: UnifiedAccountClient[] = [];
   for (const account of accounts) {
@@ -815,7 +824,7 @@ export function dedupeUnifiedAccounts(accounts: UnifiedAccountClient[]): Unified
       continue;
     }
     const mailboxes = account.mailboxes.filter((m) => {
-      const k = key(account.jmapAccountId, m.originalId ?? m.id);
+      const k = key(account, m.originalId ?? m.id);
       if (seen.has(k)) return false;
       seen.add(k);
       return true;

stores/email-store.ts

@@ -18,7 +18,7 @@ import { emailSummary, emailToReadView } from "@/lib/plugin-projection";
 import { resolveThreadRoute } from "@/lib/thread-routing";
 import { emailKeyFor, threadKeyFor, threadIdFromKey, KEYWORD_PREFIX, KEYWORD_PREFIX_LEGACY } from "@/lib/thread-utils";
 import type { ExternalSearchResult } from "@/lib/plugin-types";
-import { positionsByAccount, fetchUnifiedEmails, fetchUnifiedMailboxCounts, searchUnifiedEmails, advancedSearchUnifiedEmails, fetchCrossViewEmails, searchCrossViewEmails, advancedSearchCrossViewEmails, fetchTagEmails, trashAndJunkIds, searchAcrossAccounts, advancedSearchAcrossAccounts, getCrossUnreadTotal, dedupeUnifiedAccounts, type AcrossAccountsSearchOptions, type UnifiedAccountClient, type UnifiedMailboxCounts } from "@/lib/unified-mailbox";
+import { positionsByAccount, fetchUnifiedEmails, fetchUnifiedMailboxCounts, searchUnifiedEmails, advancedSearchUnifiedEmails, fetchCrossViewEmails, searchCrossViewEmails, advancedSearchCrossViewEmails, fetchTagEmails, trashAndJunkIds, searchAcrossAccounts, advancedSearchAcrossAccounts, getCrossUnreadTotal, dedupeUnifiedAccounts, unifiedServerKey, type AcrossAccountsSearchOptions, type UnifiedAccountClient, type UnifiedMailboxCounts } from "@/lib/unified-mailbox";
 import { defaultSearchScopeFor, isAllFoldersSearchScope, SEARCH_SCOPE_ALL_FOLDERS } from "@/lib/search-scope-folders";
 import { useAuthStore } from "@/stores/auth-store";
 import { pathNamesMailFolder } from "@/lib/deep-links";
@@ -1492,7 +1492,7 @@ export async function buildUnifiedAccountClients(
   const ownLoginJmapIds = new Set<string>();
   for (const a of authAccounts) {
     const c = allClients.get(a.id);
-    if (c) ownLoginJmapIds.add(c.getAccountId());
+    if (c) ownLoginJmapIds.add(`${unifiedServerKey(c)} ${c.getAccountId()}`);
   }
   // Every login at once rather than one after the other: the slowest login,
   // not the sum of all of them, bounds how long the scope takes.
@@ -1548,7 +1548,7 @@ export async function buildUnifiedAccountClients(
           // in the owner account instead of falling back to the active account.
           // When the owner is logged in too, its own (un-namespaced) list wins:
           // dedupeUnifiedAccounts routes that folder through the owner's login.
-          if (!ownLoginJmapIds.has(ownerId)) publish(ownerId, ownerMailboxes);
+          if (!ownLoginJmapIds.has(`${unifiedServerKey(c)} ${ownerId}`)) publish(ownerId, ownerMailboxes);
         }
       }
     } catch {