fix: guard note loading without active vault

src/hooks/useTabManagement.test.ts

@@ -160,6 +160,19 @@ describe('useTabManagement (single-note model)', () => {
       )
       warnSpy.mockRestore()
     })
+
+    it('returns to the empty state when no active vault is selected', async () => {
+      const { mockInvoke } = await import('../mock-tauri')
+      vi.mocked(mockInvoke).mockRejectedValueOnce(new Error('No active vault selected'))
+      const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
+
+      const { result } = renderHook(() => useTabManagement())
+      await selectNote(result, { path: '/vault/note/orphaned.md', title: 'Orphaned Note' })
+
+      expect(result.current.tabs).toEqual([])
+      expect(result.current.activeTabPath).toBeNull()
+      warnSpy.mockRestore()
+    })
   })
 
   describe('handleReplaceActiveTab', () => {
@@ -328,6 +341,24 @@ describe('useTabManagement (single-note model)', () => {
       await vi.waitFor(() => expect(vi.mocked(mockInvoke)).toHaveBeenCalledTimes(1))
     })
 
+    it('swallows no-active-vault prefetch failures and lets a later open recover', async () => {
+      const { mockInvoke } = await import('../mock-tauri')
+      vi.mocked(mockInvoke)
+        .mockRejectedValueOnce(new Error('No active vault selected'))
+        .mockResolvedValueOnce('# Recovered content')
+
+      prefetchNoteContent('/vault/note/recovered.md')
+      await vi.waitFor(() => expect(vi.mocked(mockInvoke)).toHaveBeenCalledTimes(1))
+      await Promise.resolve()
+      await Promise.resolve()
+
+      const { result } = renderHook(() => useTabManagement())
+      await selectNote(result, { path: '/vault/note/recovered.md', title: 'Recovered' })
+
+      expect(result.current.tabs[0].content).toBe('# Recovered content')
+      expect(vi.mocked(mockInvoke)).toHaveBeenCalledTimes(2)
+    })
+
     it('serves refreshed cached content after a save replaces stale prefetched data', async () => {
       const mockInvoke = await prefetchResolvedContent('/vault/note/saved.md', '# Stale prefetched content')
       vi.mocked(mockInvoke).mockResolvedValue('# Persisted content')

src/hooks/useTabManagement.ts

@@ -73,7 +73,10 @@ function requestNoteContent({ path }: Pick<NoteContentCacheEntry, 'path'>): Note
  *  Cache is short-lived: cleared on vault reload via clearPrefetchCache(). */
 export function prefetchNoteContent(path: string): void {
   if (prefetchCache.has(path)) return
-  requestNoteContent({ path })
+  void requestNoteContent({ path }).promise.catch((error) => {
+    if (isNoActiveVaultSelectedError(error)) return
+    console.warn('Failed to prefetch note content:', error)
+  })
 }
 
 export function cacheNoteContent(path: string, content: string): void {
@@ -189,6 +192,15 @@ function isMissingNotePathError(error: unknown): boolean {
   return /does not exist|not found|enoent/i.test(message)
 }
 
+function isNoActiveVaultSelectedError(error: unknown): boolean {
+  const message = error instanceof Error
+    ? error.message
+    : typeof error === 'string'
+      ? error
+      : String(error)
+  return /no active vault selected/i.test(message)
+}
+
 function shouldApplyLoadedEntry(options: {
   seq: number
   navSeqRef: React.MutableRefObject<number>
@@ -238,6 +250,13 @@ function handleEntryLoadFailure(options: {
 
   console.warn('Failed to load note content:', error)
   if (navSeqRef.current !== seq) return
+  if (isNoActiveVaultSelectedError(error)) {
+    clearPrefetchCache()
+    clearTabs(tabsRef, setTabs)
+    syncActiveTabPath(activeTabPathRef, setActiveTabPath, null)
+    failNoteOpenTrace(entry.path, 'missing-active-vault')
+    return
+  }
   if (isMissingNotePathError(error)) {
     clearTabs(tabsRef, setTabs)
     syncActiveTabPath(activeTabPathRef, setActiveTabPath, null)