addParticipant + updateParticipant used sortParticipantsByInitiative (stable
sort, tie-break = original array index). That destroyed manually-dragged tie
order when a drag moved a same-init pair — violated the slot-not-sort design
(docs/INITIATIVE_ORDERING.md: 'Re-slotting on add/edit must preserve
drag-established tie order').
Fix: new slotIndexForInit(list, init) returns splice index into the CURRENT
list (initiative-descending). addParticipant inserts there; updateParticipant
re-inserts only when initiative changed (unrelated edits keep slot — avoids
mid-round rotation dupes surfaced by the 100-round combat test).
Tests:
- turn.slot-not-sort.test.js: drag tie order survives add/edit (4 cases).
- static.no-sort.test.js: errs if .sort( added outside allowlist
(sortParticipantsByInitiative only). Verified by injecting a stray sort —
guard caught it.
Move activeDisplay lifecycle to shared (one path, not duplicated in App):
- activateDisplay({campaignId, encounterId})
- clearDisplay()
- toggleHidePlayerHp(current)
All 6 App sites wired (start/end/2×delete-encounter/delete-campaign/hp-toggle).
Existing {patch,log} return shape preserved. No interface changes.
Combat.scenario.test.js rewritten to call shared directly, no React:
- Same actions as old UI version (roster chars, monsters, addAll, hp-toggle×2,
start, 100 rounds of damage/heal/conditions/toggle/edit/deathsave/pause/
resume/add/remove, end). Same funcs, same order, same data.
- Models two firestore docs (encounter + activeDisplay) via shared patches.
- Run time: 72s -> 4ms.
Both suites green: shared 91/91, App 77/77.
Extract shared nextActiveAfter() advance core. Both nextTurn and
computeTurnOrderAfterRemoval delegate to it — single source of truth,
eliminates drift risk where one path changes and the other doesn't.
Previously two separate advance implementations computed the same
target, but any future edit to one would silently desync deact-current
advance from normal nextTurn advance.
Replay (scripts/replay-combat.js):
- Move turn-line print before mutations (event order = reality)
- Emit [pointer X→Y] lines when a mutation advances currentTurnParticipantId
- Emit [pointer X→Y wrap] when round bumps (removal-wrap case)
- Skip pointer emission for nextTurn (label=null) — already logged via turn line
Parser (scripts/analyze-turns.js):
- Parse [pointer X→Y wrap] events
- Credit pointer-target as acted (deact-current advance = turn pointer)
- Wrap pointer credits NEXT round (not current) — fixes cross-round false skip
- Drop currentRemoved special-case — pointer lines make skip check precise
Tests:
- shared/tests/turn.dry.test.js: 3 tests lock deact-current advance ==
nextTurn advance (mid-round, inactive-skipper, wrap+round-bump). RED
catches future drift.
Results: 500-round replay now 0 real skips, 0 double-acts (was 5+3).
Shared suite: 79 green + 1 RED (BUG-6 reorder, intentional).
Removal of current participant when no active after → advance to order[0]
+ bump round. Without bump, nextTurn replays whole round (BUG-5 pattern).
Parser 500-40b: 24 skips/1 double (was 46/64). Down not zero. Remaining
skips = replay async stale read (getDoc between turns), not turn.js.
Root cause: addParticipant appended participant to participants[] without
checking id uniqueness. Two participants with same id in array. On
togglePause resume, turnOrderIds rebuilt via sort → dup id appears twice.
nextTurn then stuck repeating that id (rotation breaks).
This was the enabling step for BUG-1's full corruption (audit chain):
pause blocks advance → totalTurns frozen → addParticipant re-adds
same r${totalTurns} id → resume dup → nextTurn stuck.
Fix: throw on duplicate id in addParticipant. Caller must use fresh id
(crypto.randomUUID in App, replay already does).
Evidence:
- Test: 'addParticipant rejects duplicate id' (was test.skip, now live).
- Pre-fix: 1 RED (Received function did not throw).
- Post-fix: 50 green (shared), 23 green (server), 62 green (FE).
- Reachability in normal app: low (App uses crypto.randomUUID) but no
guard existed before. Defensive + unblocks BUG-1 isolation.
No other behavior changed.
david raistrick