Add hs.audiodevice

[cmsj]

• Checkpoint
• Fix some compiler warnings
• Fix channelCount property
• Fix docstrings issues and regenerate docs

[greptile-apps]

Greptile Summary

This PR introduces hs.audiodevice, a new Hammerspoon module that exposes CoreAudio device enumeration, property inspection, volume/mute/balance/sample-rate control, data-source selection, default-device assignment, and property-change watchers — both at the per-device level and at the system level — to JavaScript. The implementation follows the established module pattern (ModuleRoot registration, JSExport protocol, getOrCreate lifecycle) and includes a comprehensive integration test suite that gracefully degrades on CI runners with no audio hardware.

• HSAudioDevice.swift — core device object with CoreAudio helper layer and a per-device watcher that uses AudioObjectAddPropertyListenerBlock.
• HSAudioDeviceManager.swift — singleton weak-reference cache ensuring identity stability for the same AudioObjectID across JS calls.
• HSAudioDeviceModule.swift — module entry point with system-level watcher for device add/remove and default-device changes.
• One logic bug: in HSAudioDevice.startWatcher(), selfRetain = self is set unconditionally before the listener-registration loop. If every candidate property fails to register (e.g. on a device that exposes none of the watched selectors, or if all AudioObjectAddPropertyListenerBlock calls fail), watcherRegistrations stays empty, stopWatcher() short-circuits before clearing selfRetain, and the device leaks permanently.
• Two style issues: both HSAudioDevice.deinit and HSAudioDeviceModule.deinit use raw print() rather than the project-standard AKTrace.

Confidence Score: 4/5

• Safe to merge after fixing the selfRetain leak in startWatcher() and replacing the two debug print calls with AKTrace.
• The module is well-structured and comprehensive, with CI-resilient tests and clean CoreAudio wrappers. The selfRetain issue is a real memory leak but only manifests in the unlikely edge case where a device has none of the seven watched properties (or all listener registrations fail) — normal audio devices will always have at least one. The print calls are a minor polish issue. Everything else looks solid.
• Hammerspoon 2/Modules/hs.audiodevice/HSAudioDevice.swift — startWatcher() self-retain placement.

Important Files Changed

Filename	Overview
Hammerspoon 2/Modules/hs.audiodevice/HSAudioDevice.swift	New file implementing the per-device JS API. Two issues: a memory leak in startWatcher() where selfRetain = self is set before confirming any listener was registered (if none register, stopWatcher() never clears it), and a leftover print in deinit that should use AKTrace.
Hammerspoon 2/Modules/hs.audiodevice/HSAudioDeviceManager.swift	New file providing a shared weak-reference cache for HSAudioDevice instances. Clean implementation with correct weak-ref pattern, prune helper, and stopAllWatchers for module shutdown.
Hammerspoon 2/Modules/hs.audiodevice/HSAudioDeviceModule.swift	New module entry point with system-level watcher and device enumeration. Minor: leftover print in deinit should use AKTrace. System watcher's selfRetain pattern is not used here (module lifetime is managed externally), so no leak concern.
Hammerspoon 2/Engine/ModuleRoot.swift	Minimal change: adds audiodevice property to both the protocol and the implementation, consistent with the existing pattern.
Hammerspoon 2Tests/IntegrationTests/HSAudioDeviceIntegrationTests.swift	Comprehensive integration tests with CI-safe guards that skip device-dependent tests when no audio hardware is present. Good coverage of enumeration, identity, channels, volume, data sources, and watcher lifecycle.

Prompt To Fix All With AI

This is a comment left during a code review.
Path: Hammerspoon 2/Modules/hs.audiodevice/HSAudioDevice.swift
Line: 373-375

Comment:
**Debug `print` statement in `deinit`**

This `print(...)` call looks like a leftover debug trace. Other lifecycle logs in the module use `AKTrace`, and shipping production code with `print` to stdout is generally noisy. Consider replacing with `AKTrace` or removing it entirely.

```suggestion
    deinit {
        AKTrace("deinit of HSAudioDevice id=\(objectID)")
    }
```

How can I resolve this? If you propose a fix, please make it concise.

---

This is a comment left during a code review.
Path: Hammerspoon 2/Modules/hs.audiodevice/HSAudioDevice.swift
Line: 590-618

Comment:
**`selfRetain` set before confirming any listener was registered**

`selfRetain = self` is assigned unconditionally at the top of `startWatcher()`, before the loop that adds CoreAudio property listeners. If every candidate either lacks the property or fails `AudioObjectAddPropertyListenerBlock`, `watcherRegistrations` remains empty. At that point:

- `watcherIsActive()` returns `false` (correct)
- `stopWatcher()` early-returns immediately because `watcherRegistrations.isEmpty` is true — so it never clears `selfRetain`

The device therefore retains itself permanently, causing a memory leak. The fix is to move `selfRetain = self` to after the loop, gated on at least one successful registration:

```swift
@objc func startWatcher() {
    guard unsafe watcherRegistrations.isEmpty else { return }

    let candidates: [(AudioObjectPropertySelector, AudioObjectPropertyScope)] = [ ... ]
    for (selector, scope) in candidates {
        // ... same as before
    }

    guard !watcherRegistrations.isEmpty else { return }
    selfRetain = self  // prevent GC while watcher is active
    AKTrace(...)
}
```

How can I resolve this? If you propose a fix, please make it concise.

---

This is a comment left during a code review.
Path: Hammerspoon 2/Modules/hs.audiodevice/HSAudioDeviceModule.swift
Line: 110-112

Comment:
**Debug `print` statement in `deinit`**

Same pattern as in `HSAudioDevice` — this `print(...)` should use `AKTrace` (consistent with the rest of the module) or be removed before merge.

```suggestion
    deinit {
        AKTrace("Deinit of \(name)")
    }
```

How can I resolve this? If you propose a fix, please make it concise.

_{Reviews (1): Last reviewed commit: "Fix docstrings issues and regenerate doc..." | Re-trigger Greptile}

[greptile-apps]

Debug print statement in deinit

This print(...) call looks like a leftover debug trace. Other lifecycle logs in the module use AKTrace, and shipping production code with print to stdout is generally noisy. Consider replacing with AKTrace or removing it entirely.

Suggested change

	// MARK: - Capabilities
	deinit {
	AKTrace("deinit of HSAudioDevice id=\(objectID)")
	}

Prompt To Fix With AI

This is a comment left during a code review.
Path: Hammerspoon 2/Modules/hs.audiodevice/HSAudioDevice.swift
Line: 373-375

Comment:
**Debug `print` statement in `deinit`**

This `print(...)` call looks like a leftover debug trace. Other lifecycle logs in the module use `AKTrace`, and shipping production code with `print` to stdout is generally noisy. Consider replacing with `AKTrace` or removing it entirely.

```suggestion
    deinit {
        AKTrace("deinit of HSAudioDevice id=\(objectID)")
    }
```

How can I resolve this? If you propose a fix, please make it concise.

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}

[greptile-apps]

selfRetain set before confirming any listener was registered

selfRetain = self is assigned unconditionally at the top of startWatcher(), before the loop that adds CoreAudio property listeners. If every candidate either lacks the property or fails AudioObjectAddPropertyListenerBlock, watcherRegistrations remains empty. At that point:

• watcherIsActive() returns false (correct)
• stopWatcher() early-returns immediately because watcherRegistrations.isEmpty is true — so it never clears selfRetain

The device therefore retains itself permanently, causing a memory leak. The fix is to move selfRetain = self to after the loop, gated on at least one successful registration:

@objc func startWatcher() {
    guard unsafe watcherRegistrations.isEmpty else { return }

    let candidates: [(AudioObjectPropertySelector, AudioObjectPropertyScope)] = [ ... ]
    for (selector, scope) in candidates {
        // ... same as before
    }

    guard !watcherRegistrations.isEmpty else { return }
    selfRetain = self  // prevent GC while watcher is active
    AKTrace(...)
}

Prompt To Fix With AI

This is a comment left during a code review.
Path: Hammerspoon 2/Modules/hs.audiodevice/HSAudioDevice.swift
Line: 590-618

Comment:
**`selfRetain` set before confirming any listener was registered**

`selfRetain = self` is assigned unconditionally at the top of `startWatcher()`, before the loop that adds CoreAudio property listeners. If every candidate either lacks the property or fails `AudioObjectAddPropertyListenerBlock`, `watcherRegistrations` remains empty. At that point:

- `watcherIsActive()` returns `false` (correct)
- `stopWatcher()` early-returns immediately because `watcherRegistrations.isEmpty` is true — so it never clears `selfRetain`

The device therefore retains itself permanently, causing a memory leak. The fix is to move `selfRetain = self` to after the loop, gated on at least one successful registration:

```swift
@objc func startWatcher() {
    guard unsafe watcherRegistrations.isEmpty else { return }

    let candidates: [(AudioObjectPropertySelector, AudioObjectPropertyScope)] = [ ... ]
    for (selector, scope) in candidates {
        // ... same as before
    }

    guard !watcherRegistrations.isEmpty else { return }
    selfRetain = self  // prevent GC while watcher is active
    AKTrace(...)
}
```

How can I resolve this? If you propose a fix, please make it concise.

[greptile-apps]

Debug print statement in deinit

Same pattern as in HSAudioDevice — this print(...) should use AKTrace (consistent with the rest of the module) or be removed before merge.

Suggested change

	deinit {
	print("Deinit of \(name)")
	deinit {
	AKTrace("Deinit of \(name)")
	}

Prompt To Fix With AI

This is a comment left during a code review.
Path: Hammerspoon 2/Modules/hs.audiodevice/HSAudioDeviceModule.swift
Line: 110-112

Comment:
**Debug `print` statement in `deinit`**

Same pattern as in `HSAudioDevice` — this `print(...)` should use `AKTrace` (consistent with the rest of the module) or be removed before merge.

```suggestion
    deinit {
        AKTrace("Deinit of \(name)")
    }
```

How can I resolve this? If you propose a fix, please make it concise.

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}