Lumotia/docs/issues/power-assertion-macos-objc2.md

RB-08 MAJOR: PowerAssertion is a non-functional stub on macOS

Severity: MAJOR (macOS only) Path: src-tauri/src/commands/power.rs:41-121 Source: 2026-04-22 code review, originally deferred during A.1 #9 Labels: release-blocker, major, macos, platform

Current state (2026-04-23): objc2/objc2-foundation have been added behind cfg(target_os = "macos"), and the NSProcessInfo bridge now calls beginActivityWithOptions:reason: / endActivity: with the retained activity handle. Isolated cargo check validation passes for both x86_64-apple-darwin and aarch64-apple-darwin. Remaining acceptance gap: manual runtime verification on a real macOS machine (pmset -g assertions, background live session). Diagnostic reports now also include a ## Power assertions section that lists any currently active Kon assertion guards (reason, backend, acquired) at report time, which gives the tester an in-app breadcrumb alongside pmset.

Problem

begin_activity always returns Err on macOS, so PowerAssertion::begin converts to None and the guard never acquires an NSProcessInfo beginActivityWithOptions:reason: assertion. Live recording and LLM cleanup therefore run without App Nap protection on the one platform where it matters.

The stub was deliberate (A.1 #9 acceptance concession — untestable on Linux without a macOS build host). Re-flagged here so it is not forgotten before the first macOS ship.

Acceptance

• objc2 + objc2-foundation deps added to the kon crate, gated cfg(target_os = "macos").
• begin_activity calls [NSProcessInfo processInfo] beginActivityWithOptions:(NSActivityUserInitiated | NSActivityLatencyCritical) reason:reason] and retains the returned activity handle.
• end_activity calls endActivity: on the retained handle.
• Manual-test on a real macOS box: 10-minute background live session completes without throttling; pmset -g assertions shows Kon's activity during capture.

Manual verification checklist

1. Launch Kon on a real macOS machine and start a live transcription session.
2. While capture is running, background the app for at least several minutes.
3. In Terminal, run pmset -g assertions and confirm Kon appears with a user-initiated / no-idle-style assertion while the session is active.
4. While the session is still running, generate a Kon diagnostic report and confirm the ## Power assertions section lists an active entry such as reason=kon live dictation session, backend=macos, acquired=true.
5. Stop the session and rerun pmset -g assertions or regenerate the diagnostic report to confirm the assertion disappears.
6. Repeat once for the LLM cleanup path if desired (reason=kon LLM cleanup).

Fix scope

Medium. Dep addition + FFI glue + manual verification. Can be done from Linux with cargo check --target=aarch64-apple-darwin for compile validation, but runtime behaviour needs a macOS machine.

Dependencies

• Hard blocker: before first macOS build/ship.