fix: forget delegate names on sign-out and when their account is removed

lib/__tests__/sign-out-cleanup.test.ts

@@ -17,7 +17,7 @@ describe('purgeSignedOutData', () => {
   it("removes the accounts' leftovers and keeps device preferences", () => {
     for (const key of [
       'email-snapshot', 'pro-tabs', 'search-history-storage', 'calendar-storage',
-      'files-favorites', 'files-recent-files', 'files-path-stack',
+      'files-favorites', 'files-recent-files', 'files-path-stack', 'bulwark-delegate-names',
       'settings-storage', 'theme-storage', 'locale-storage', 'template-storage', 'files-view-mode',
     ]) localStorage.setItem(key, 'x');
 

lib/delegation/__tests__/known-principals.test.ts

@@ -0,0 +1,37 @@
+import { beforeEach, describe, expect, it } from 'vitest';
+import { forgetPrincipals, rememberPrincipals, rememberedPrincipals } from '../known-principals';
+import type { Principal } from '@/lib/jmap/types';
+
+const person = (id: string): Principal => ({ id, type: 'individual', name: `${id}@example.org`, email: `${id}@example.org` });
+
+beforeEach(() => localStorage.clear());
+
+describe('known principals', () => {
+  it('keeps names per account', () => {
+    rememberPrincipals('acc-1', [person('ck')]);
+    rememberPrincipals('acc-2', [person('cj')]);
+    expect([...rememberedPrincipals('acc-1').keys()]).toEqual(['ck']);
+    expect([...rememberedPrincipals('acc-2').keys()]).toEqual(['cj']);
+  });
+
+  it('forgets one account and leaves the others', () => {
+    rememberPrincipals('acc-1', [person('ck')]);
+    rememberPrincipals('acc-2', [person('cj')]);
+    forgetPrincipals('acc-1');
+    expect(rememberedPrincipals('acc-1').size).toBe(0);
+    expect([...rememberedPrincipals('acc-2').keys()]).toEqual(['cj']);
+  });
+
+  it('leaves no key behind when the last account goes', () => {
+    rememberPrincipals('acc-1', [person('ck')]);
+    forgetPrincipals('acc-1');
+    expect(localStorage.getItem('bulwark-delegate-names')).toBeNull();
+  });
+
+  it('keeps at most 200 per account, dropping the oldest', () => {
+    rememberPrincipals('acc-1', Array.from({ length: 205 }, (_, i) => person(`p${i}`)));
+    const ids = [...rememberedPrincipals('acc-1').keys()];
+    expect(ids).toHaveLength(200);
+    expect(ids[0]).toBe('p5');
+  });
+});

lib/delegation/known-principals.ts

@@ -3,14 +3,17 @@
  * browser. Stalwart 1.0 with directory queries off (its default) won't name
  * a principal the user shares with unless that principal also shares
  * something back, so the "Who has access" list would otherwise show bare
- * ids for the very people the user just picked by name. Per account, at
- * most MAX entries, and only a convenience: losing it costs names, not
- * access.
+ * ids for the very people the user just picked by name. Only the people
+ * who have access and the one just picked are kept, never the directory;
+ * per account, at most MAX entries, gone when the account is removed or
+ * everyone signs out. A convenience: losing it costs names, not access.
  */
 
 import type { Principal } from '@/lib/jmap/types';
 
-const STORAGE_KEY = 'bulwark-delegate-names';
+/** Purged when everyone signs out (lib/sign-out-cleanup.ts). */
+export const DELEGATE_NAMES_KEY = 'bulwark-delegate-names';
+const STORAGE_KEY = DELEGATE_NAMES_KEY;
 const MAX = 200;
 
 type Entry = Pick<Principal, 'id' | 'name' | 'email' | 'type'>;
@@ -50,3 +53,17 @@ export function rememberedPrincipals(accountKey: string): Map<string, Principal>
   const own = readStore()[accountKey] ?? {};
   return new Map(Object.values(own).map((entry) => [entry.id, entry as Principal]));
 }
+
+/** Forget the names kept for one account (it was removed from this browser). */
+export function forgetPrincipals(accountKey: string): void {
+  if (!accountKey) return;
+  try {
+    const store = readStore();
+    if (!(accountKey in store)) return;
+    delete store[accountKey];
+    if (Object.keys(store).length === 0) localStorage.removeItem(STORAGE_KEY);
+    else localStorage.setItem(STORAGE_KEY, JSON.stringify(store));
+  } catch {
+    // storage unavailable
+  }
+}

lib/sign-out-cleanup.ts

@@ -24,6 +24,8 @@ const SIGNED_OUT_STORAGE_KEYS = [
   'files-recent-files',
   'files-last-parent-id',
   'files-path-stack',
+  // Names of the people the user gave access to (Settings > Sharing).
+  'bulwark-delegate-names',
 ];
 
 const SIGNED_OUT_SIGNAL = 'bulwark:signed-out';

stores/__tests__/auth-store-remove-viewed-account.test.ts

@@ -59,6 +59,15 @@ describe('removing a login that is not the active one', () => {
     useEmailStore.setState(initialEmail);
   });
 
+  it("forgets the names of the people it gave access to, and keeps the other login's", () => {
+    localStorage.setItem('bulwark-delegate-names', JSON.stringify({
+      [a]: { ck: { id: 'ck', name: 'carol@example.org', email: 'carol@example.org', type: 'individual' } },
+      [b]: { cj: { id: 'cj', name: 'bob@example.org', email: 'bob@example.org', type: 'individual' } },
+    }));
+    useAuthStore.getState().removeAccount(b);
+    expect(Object.keys(JSON.parse(localStorage.getItem('bulwark-delegate-names')!))).toEqual([a]);
+  });
+
   it('leaves its folder open in the Pro sidebar, so deleting the rows shown deletes nothing in the active login', async () => {
     const row = message();
     useEmailStore.setState({

stores/auth-store.ts

@@ -20,6 +20,7 @@ import { isEmbedded, notifyParent } from '@/lib/iframe-bridge';
 import { snapshotAccount, restoreAccount, clearAllStores, evictAccount, evictAll, forgetAccountRows } from '@/lib/account-state-manager';
 import { clearAllPluginStorage, clearPluginStorageForAccount } from '@/lib/plugin-sandbox/storage-scope';
 import { broadcastSignOut, onSignedOutElsewhere, purgeSignedOutData } from '@/lib/sign-out-cleanup';
+import { forgetPrincipals } from '@/lib/delegation/known-principals';
 import { useSearchHistoryStore } from './search-history-store';
 import { useCalendarNotificationStore } from './calendar-notification-store';
 import { usePolicyStore } from './policy-store';
@@ -2230,6 +2231,7 @@ export const useAuthStore = create<AuthState>()(
           clients.delete(accountId);
           evictAccount(accountId);
           accountStore.removeAccount(accountId);
+          forgetPrincipals(accountId);
           if (!wasDemoMode) clearPluginStorageForAccount(accountId);
         }
 
@@ -2368,6 +2370,7 @@ export const useAuthStore = create<AuthState>()(
         evictAccount(accountId);
         forgetAccountRows(accountId, get().client);
         accountStore.removeAccount(accountId);
+        forgetPrincipals(accountId);
         clearPluginStorageForAccount(accountId);
       },