fix: list files again when the real client takes over from the local copy

integration/tests/22-ent-offline.spec.ts

@@ -842,7 +842,9 @@ test('nothing of a kept message is readable on the device', async ({ browser })
   await enableOffline(page);
   await expect(async () => {
     const client = await jmapAs(ENT.alice);
-    const total = await client.request([['Email/query', { accountId: client.accountId, calculateTotal: true, limit: 0 }, '0']]);
+    // The default window: the old message of the cap test stays out.
+    const after = new Date(Date.now() - 90 * 86_400_000).toISOString().replace(/\.\d+Z$/, 'Z');
+    const total = await client.request([['Email/query', { accountId: client.accountId, filter: { after }, calculateTotal: true, limit: 0 }, '0']]);
     expect(await keptMessages(page)).toBeGreaterThanOrEqual(total.methodResponses[0][1].total);
   }).toPass({ timeout: 180_000, intervals: [2000] });
   await toMail(page);

stores/__tests__/file-store.test.ts

@@ -1,4 +1,4 @@
-import { describe, it, expect, beforeEach } from 'vitest';
+import { describe, it, expect, beforeEach, vi } from 'vitest';
 import { useFileStore, linkedPreviewResource, resourceServerRef, sharedFilesLocation } from '../file-store';
 import type { IJMAPClient } from '@/lib/jmap/client-interface';
 import type { FileNode } from '@/lib/jmap/types';
@@ -106,6 +106,24 @@ const file = (id: string, name: string, parentId: string | null): FileNode => ({
   id, parentId, name, type: 'text/plain', blobId: `b-${id}`, size: 10, created: '', modified: '',
 });
 
+describe('after a start from the local copy', () => {
+  it('lists again when the real client takes over, and the error of asking the device goes', async () => {
+    const local = makeMockClient([]);
+    (local as unknown as { isOfflineOnly: () => boolean }).isOfflineOnly = () => true;
+    local.listAllFileNodes = async () => { throw new Error('Not available offline'); };
+    useFileStore.setState({ client: null, supportsFiles: null, resources: [], error: null, currentParentId: null, pathStack: [{ id: null, name: '' }] } as never);
+    useFileStore.getState().initClient(local as unknown as IJMAPClient, 'acc');
+    useFileStore.setState({ supportsFiles: true });
+    await useFileStore.getState().navigate(null);
+    expect(useFileStore.getState().error).toBeTruthy();
+
+    const real = makeMockClient([{ id: 'f1', parentId: null, name: 'kept.txt', type: 'text/plain', blobId: 'b', size: 1, created: '', modified: '' }]);
+    useFileStore.getState().initClient(real as unknown as IJMAPClient, 'acc');
+    await vi.waitFor(() => expect(useFileStore.getState().resources.map((r) => r.name)).toEqual(['kept.txt']));
+    expect(useFileStore.getState().error).toBeFalsy();
+  });
+});
+
 describe('file-store hierarchy (issue #379)', () => {
   beforeEach(() => {
     useFileStore.setState({

stores/file-store.ts

@@ -649,9 +649,15 @@ export const useFileStore = create<FileState>((set, get) => ({
   })(),
 
   initClient: (client: IJMAPClient, accountId?: string | null) => {
+    const before = get().client as (IJMAPClient & { isOfflineOnly?: () => boolean }) | null;
     const patch: Partial<FileState> = { client };
     if (accountId !== undefined) patch.currentAccountId = accountId;
     set(patch);
+    // A start from the local copy: the real client just took over, and what's
+    // listed is what the device had, or the error of asking it.
+    const offlineBefore = before !== client && before?.isOfflineOnly?.();
+    const offlineNow = (client as IJMAPClient & { isOfflineOnly?: () => boolean }).isOfflineOnly?.();
+    if (offlineBefore && !offlineNow && get().supportsFiles) void get().refresh();
   },
 
   clearClient: () => {