Make stopRecording() async to avoid reading incomplete WAV

[eherrerosj]

Summary

• Recorder.stopRecording() was fire-and-forget: it dispatched the stop to a serial audio queue and returned right away
• The transcription pipeline could then try to read the WAV file before CoreAudioRecorder had finished closing it
• Now async, using withCheckedContinuation to actually wait for the stop to finish

Test plan

• Record a transcription, check it processes correctly
• Rapid start/stop cycles — no deadlocks
• Cancel mid-recording, confirm it still works

🤖 Generated with Claude Code

---

Summary by cubic

Make Recorder.stopRecording() async and wait for the hardware queue to finish so WAV files are fully closed before reading. Also fixes race conditions during cancel and rapid start/stop.

• Bug Fixes

  • Made stopRecording() async with withCheckedContinuation and wait on audioSetupQueue; capture and clear recorder/onAudioChunk before awaiting to avoid reentrancy and stale cleanup.
  • Updated call sites to await the stop in Recorder and VoiceInkEngine; capture recordedFile before awaiting and only nil it if unchanged to keep cancel paths safe.

• Migration

  • Callers must await recorder.stopRecording().

^{Written for commit 0478469. Summary will update on new commits.}

[cubic-dev-ai]

2 issues found across 2 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="VoiceInk/Recorder.swift">

<violation number="1" location="VoiceInk/Recorder.swift:167">
P1: `stopRecording()` became reentrancy-unsafe: it awaits before clearing shared state, so interleaved `startRecording()` can be overwritten by stale cleanup.</violation>
</file>

<file name="VoiceInk/Whisper/VoiceInkEngine.swift">

<violation number="1" location="VoiceInk/Whisper/VoiceInkEngine.swift:144">
P1: Awaiting stop before clearing `recordedFile` creates a re-entrancy race that can wipe a newer recording URL during rapid cancel/restart.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

1 issue found across 2 files (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="VoiceInk/Recorder.swift">

<violation number="1" location="VoiceInk/Recorder.swift:166">
P1: `stopRecording()` applies unconditional post-await cleanup that can run after a new recording starts, causing incorrect recording state and media restoration mid-recording.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P1: stopRecording() applies unconditional post-await cleanup that can run after a new recording starts, causing incorrect recording state and media restoration mid-recording.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At VoiceInk/Recorder.swift, line 166:

<comment>`stopRecording()` applies unconditional post-await cleanup that can run after a new recording starts, causing incorrect recording state and media restoration mid-recording.</comment>

<file context>
@@ -160,9 +160,14 @@ class Recorder: NSObject, ObservableObject {
+        // Capture and clear shared state before awaiting so a concurrent
+        // startRecording() won't have its new state overwritten when we resume.
         let currentRecorder = self.recorder
+        recorder = nil
+        onAudioChunk = nil
+
</file context>