fix(desktop): stream voice replies from live message deltas

apps/desktop/src/app/chat/composer/hooks/use-composer-voice-stream-subscription.test.tsx

@@ -0,0 +1,108 @@
+import { act, renderHook } from '@testing-library/react'
+import { beforeEach, expect, test, vi } from 'vitest'
+
+const mocks = vi.hoisted(() => {
+  let value: unknown[] = []
+  const listeners = new Set<(next: unknown[], old: unknown[]) => void>()
+
+  const messages = {
+    get: () => value,
+    listen: (listener: (next: unknown[], old: unknown[]) => void) => {
+      listeners.add(listener)
+
+      return () => listeners.delete(listener)
+    },
+    set: (next: unknown[]) => {
+      const old = value
+      value = next
+      listeners.forEach(listener => listener(next, old))
+    },
+    subscribe: (listener: (next: unknown[], old: unknown[]) => void) => {
+      listeners.add(listener)
+      listener(value, value)
+
+      return () => listeners.delete(listener)
+    }
+  }
+
+  const useVoiceConversation = vi.fn(() => ({
+    end: vi.fn(async () => undefined),
+    level: 0,
+    muted: false,
+    start: vi.fn(async () => undefined),
+    status: 'idle' as const,
+    stopTurn: vi.fn(),
+    toggleMute: vi.fn()
+  }))
+
+  return { messages, useVoiceConversation }
+})
+
+vi.mock('@/i18n', () => ({
+  useI18n: () => ({
+    t: {
+      assistant: { thread: { readAloudFailed: 'read aloud failed' } },
+      notifications: { voice: { sayStopToEnd: (phrase: string) => phrase } },
+      settings: { config: { autosaveFailed: 'autosave failed' } }
+    }
+  })
+}))
+vi.mock('../scope', () => ({
+  useComposerScope: () => ({ $messages: mocks.messages }),
+  useComposerSurfaceId: () => null
+}))
+vi.mock('./use-voice-conversation', () => ({ useVoiceConversation: mocks.useVoiceConversation }))
+vi.mock('./use-voice-recorder', () => ({
+  useVoiceRecorder: () => ({ dictate: vi.fn(), voiceActivityState: null, voiceStatus: 'idle' })
+}))
+vi.mock('./use-auto-speak-replies', () => ({ useAutoSpeakReplies: vi.fn() }))
+vi.mock('@/lib/haptics', () => ({ triggerHaptic: vi.fn() }))
+vi.mock('@/lib/wake-indicator', () => ({
+  clearWakeIndicator: vi.fn(),
+  syncWakeIndicatorWithVoice: vi.fn(() => false)
+}))
+vi.mock('@/store/ambient', () => ({ ownsAmbientCue: vi.fn(async () => true) }))
+vi.mock('@/store/notifications', () => ({ notify: vi.fn(), notifyError: vi.fn() }))
+vi.mock('@/store/wake-word', () => ({
+  resumeWakeAfterVoice: vi.fn(async () => undefined),
+  stopClientCapture: vi.fn(async () => undefined)
+}))
+
+import { useComposerVoice } from './use-composer-voice'
+
+beforeEach(() => {
+  mocks.messages.set([])
+  mocks.useVoiceConversation.mockClear()
+})
+
+test('re-renders the voice loop when an in-progress assistant delta lands', () => {
+  renderHook(() =>
+    useComposerVoice({
+      busy: true,
+      clearDraft: vi.fn(),
+      disabled: false,
+      focusInput: vi.fn(),
+      insertText: vi.fn(),
+      maxRecordingSeconds: 60,
+      onSubmit: vi.fn(async () => true),
+      onTranscribeAudio: vi.fn(async () => ''),
+      sessionId: 'voice-session',
+      target: 'main'
+    })
+  )
+
+  const callsBeforeDelta = mocks.useVoiceConversation.mock.calls.length
+
+  act(() => {
+    mocks.messages.set([
+      {
+        id: 'assistant-stream',
+        pending: true,
+        role: 'assistant',
+        parts: [{ type: 'text', text: 'Natural selection is' }]
+      }
+    ])
+  })
+
+  expect(mocks.useVoiceConversation.mock.calls.length).toBeGreaterThan(callsBeforeDelta)
+})

apps/desktop/src/app/chat/composer/hooks/use-composer-voice.ts

@@ -67,6 +67,11 @@ export function useComposerVoice({
   const { t } = useI18n()
   // A tile's composer speaks ITS transcript, not the primary chat's.
   const { $messages } = useComposerScope()
+  // Voice conversation speech is driven by in-progress assistant deltas. Keep
+  // this hook subscribed so its speech effect runs before busy flips false;
+  // pendingTurnResponse still reads $messages.get() so the 150 ms feeder sees
+  // every later delta instead of a stale render-time snapshot.
+  useStore($messages)
   const [voiceConversationActive, setVoiceConversationActive] = useState(false)
   // Engine selection is latched at conversation START (a Settings change
   // applies to the next conversation, never mid-call).