[lawrencecchen]

Summary

Base red on feat-cmux-next: CmuxNextAppTests.UpdateInstallCheckTests crashes in theRelaunchRecordsTheInstallAndTheNextLaunchJudgesIt (UpdateRelaunchFocus.swift:99, "Unexpectedly found nil while implicitly unwrapping an Optional value").

Cause: the test calls updaterWillRelaunchApplication(), which reads UpdaterService.frontmost. Its default is AppKit's answer (UpdateFrontmostApp.current()), which reads NSApp.isActive. The package-test lane runs each suite in its own process, and this suite makes no NSApplication, so NSApp is nil and the read traps. The suite passed only when an earlier suite in the same process had made NSApplication.shared.

Fix: the seam exists for tests ("AppKit in the app, a fake in tests"); UpdateRelaunchFocusTests and UpdateRelaunchHandoffTests set it. The suite's helper now sets it too (this app frontmost, as for a clicked Restart to Update). No product change: the app always has NSApp.

Culprit: 6229004 (#31178) added the suite without the fake.

Owner: no OWNERS.md row covers CmuxNextUpdater.

Testing

Command: cmux-ci run --class light --display --script scripts/ci/package-test-lane.sh --ref SHA --arg=suite --arg=Packages/macOS/CmuxNext --arg=CmuxNextAppTests.UpdateInstallCheckTests (5 runs in one step).

• Base (feat 73eaec7 on cmuxs-Mac-mini and cmux11s): the suite crashes at UpdateRelaunchFocus.swift:99.
• Tip: job a554671b75a6b853405d5c5d at feat 11dfe91 (cmux8s) is red on the first two of five rounds for this suite.
• Head: job 563602e40b08edfe6ed6d384 (cmux-austin-mini-0) at b356d59: the suite passed 5 of 5, no crash.

Each job's lane summary is red for a reason outside this change: on these hosts the target's XCTest pass aborts (signal 6, after Contacts/AddressBook CoreData store errors) or hangs ~680-900 s with no test in flight, after the Swift Testing pass. The Swift Testing results below are the suite's own.

Observed / Not run

Observed: the fleet runs above. python3 scripts/cmux-next/prepush-gate.py passes.
Not run: no app build; test-only change.

Changelog

none

[blacksmith-sh]

Found 6 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmphs1rmo7t/summary-fail.json (live):/summary-fail.json (live):	View Logs
/tmp/tmpoe7u9_6w/summary-missing.json (live):/summary-missing.json (live):	View Logs
[new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows/ [new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows	View Logs
[new_workspaces] the window draws no frames/[new_workspaces] the window draws no frames	View Logs
[tabs] debug.tab_switch timed 0 of 40 switches/ [tabs] debug.tab_switch timed 0 of 40 switches	View Logs
[tabs] the window draws no frames/[tabs] the window draws no frames	View Logs

^{Need help on this PR? Tag @codesmith-bot with what you need.}

[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review b356d59: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr33093 -f ref=base-red-update-install-check -f platform=macos -f backend_mode=local

red: cmux-next checks (god files, concurrency, crash safety, l10n); no finished base run on 6b31a88 to compare; do not merge until green; see lane-rules

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4160373381601 (d485585f77)
• cmux NEXT nightly 1.0.0-nightly.4160614853601 (0e8eb9bf99)

[lawrencecchen]

Review (independent review subagent, Opus 5.5 claude-opus-5-5, read-only): SHIP at b356d59

• The cause is correct. UpdateFrontmostApp.current() reads NSApp.isActive with no nil check (UpdateRelaunchFocus.swift:99). Its only callers run inside Sparkle install callbacks, and AppServices.swift:572 is the only code that makes an UpdaterService. So NSApp is never nil on this path in the app. Only the test process has no NSApp.
• The test is not weakened. No assertion changes. The fake front-app hook is the same seam its sibling suites use (UpdateRelaunchFocusTests.swift:22,125, UpdateRelaunchHandoffTests.swift:19). Every test runs with automaticInstallInFlight == false, so the fake's answer changes no expected result.
• No global state is left behind, and the change opens no windows.
• Fleet: UpdateInstallCheckTests passed 5 of 5 in job 563602e40b08. The lane is red overall only because of the known fleet XCTest-stage AddressBook crash (STATUS 7919/7933).

[lawrencecchen]

Correction to my review receipt above: the lanes were red overall because of the test-bundle run-loop guard, which held the main thread in xctest. It was not the macOS AddressBook store; that was only a symptom. #33023 and #33013 fixed it on feat (ecfbb44). This head is older than that fix, so its lane still shows the XCTest stage red. The suite's own result (passes at this head, fails at the tip) is unchanged. No action is needed on this PR.