feat(controller): Phase 1d-1 — state machine + reaper + pickup guard
The deterministic spine of the master controller. State machine is
pure data with 6 load-bearing invariants enforced via property tests.
Reaper resets stale-heartbeat workflow_attempts to pending. Pickup
guard transitions workflows to STUCK when an attempt has been
re-pended too many times without success.
tools/controller/state_machine.py:
- KNOWN_STATES = 12; TERMINAL_STATES = {MERGED, ABANDONED, STUCK,
CREATED_PR}. STUCK's only allowed exit is the operator-driven
operator_unstick event (back to DISCOVERED).
- 32 TRANSITIONS entries covering DISCOVERED → ANALYZING →
IMPLEMENTING ↔ AWAITING_CI / CONFLICT_RESOLVING / ESCALATING →
REVIEWING → MERGING → MERGED. Plus pickup_exhausted exits from
IMPLEMENTING/CONFLICT_RESOLVING/REVIEWING.
- 27 named events with descriptions. apply_event() lookup raises
IllegalTransitionError (lists legal events from current state)
or ValueError on unknown state (per v6 unknown-state guard).
- 6 LOAD-BEARING invariants for v1 (per v9 simplification):
1. no_path_implementing_to_reviewing_skips_ci (Hard Rule #1
constructional fix for the no-mans-land race)
2. terminal_states_have_no_exits (only STUCK→operator_unstick OK)
3. tier_monotonic_non_decreasing
4. every_pr_workflow_includes_reviewing
5. conflict_resolving_bounded (1st→IMPLEMENTING, 2nd→ESCALATING,
3rd→STUCK; structurally encoded)
6. escalation_deterministic
- reachable_from() honors cycles (DISCOVERED ∈ reachable(DISCOVERED)
via STUCK→operator_unstick path; AWAITING_CI self-loops via
ci_flake_retry).
tools/controller/reaper.py:
- reap_stale_attempts(): SELECT in_progress attempts whose
lock_heartbeat_at + lock_ttl_seconds < NOW (per-row TTL respects
per-role differences — estimator 180s, reviewer 720s, tier-2
implementer 2160s). UPDATEs status='pending', clears lock columns,
preserves pickup_count (the pickup guard handles that). Inserts
controller_events row with reason='lock-ttl-expired' per reap.
- Dialect-portable: Postgres uses interval arithmetic; SQLite uses
julianday(). Same logic either way.
tools/controller/pickup_guard.py:
- transition_exhausted_to_stuck(): finds attempts with status='pending'
AND pickup_count >= MAX_PICKUPS (default 3 per v6 blocker fix)
AND workflow not already terminal. Transitions workflow → STUCK,
marks attempt as 'reaped', inserts controller_events with
reason='attempt-pickup-exhausted' + pickup_count + max_pickups.
45 new tests:
- state_machine: basic shape (states partition, every transition uses
known states + defined events), apply_event success/error paths,
events_from + reachable_from helpers (including cycle awareness),
per-invariant zero-violations against the live table, per-invariant
monkeypatch-violations to prove the checks catch the bug class they
claim to, parametrised sanity check "every non-terminal can reach
some terminal".
- reaper: empty DB / fresh heartbeat / stale heartbeat reaped /
per-row TTL respected / event row created / only-in-progress
reaped / multiple stale attempts.
- pickup guard: empty DB / below limit / at limit / in-progress not
checked / terminal workflow skipped / event payload content /
default max_pickups matches v6.
Total: 229 controller tests; full auto_agents suite 2591 pass.
drew
976817fa22