The two 'loaded but not currently running' branches in the stop step (launchd/systemd, reached
when $OLD_PID is empty) ran 'launchctl unload'/'systemctl --user stop' with '2>/dev/null || true'
and printed 'ok' unconditionally. That swallowed a real supervisor failure (e.g. launchd or the
systemd user bus unreachable) exactly like a harmless already-stopped answer, and let the script
proceed to start a new daemon believing nothing was loaded -- the two-daemons failure fleetd #492
exists to prevent.
Adds unload_launchd_if_loaded/stop_systemd_if_loaded, applying systemd_loaded's own pattern
(capture stderr separately; a non-zero exit WITH stderr is a real failure, a non-zero exit with
empty stderr is a clean already-stopped answer) to the write side. The two call sites now use
these functions instead of the bare '|| true'.
Adds 5 tests: dies-on-real-failure and tolerates-clean-negative for each function, plus a
source-text check that the main flow calls the new functions instead of the original bare
'2>/dev/null || true'. All 5 verified by mutation (reintroducing the swallow, and separately
over-correcting to die unconditionally) -- each goes red with its own message, restores
byte-identical (full sha256), and passes a green control.
Dai Ha