From 8d04ec19fdfed195d7c6d85cd1f2900f42f5d309 Mon Sep 17 00:00:00 2001
From: Tom Boucher <trekkie@nomorestars.com>
Date: Wed, 18 Mar 2026 12:07:22 -0400
Subject: [PATCH] fix: add defensive guards against undefined .filter() in
 auto-mode dispatch/recovery (#1180)
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Auto-mode crashed with 'Cannot read properties of undefined (reading
filter)' during partial execute-task recovery when derived state was
structurally incomplete.

Added ?? [] fallback guards on all .filter()/.find()/.map() calls
that access state.registry, roadmap.slices, or similar derived arrays
in the dispatch and recovery paths:

- auto.ts: 3 state.registry.filter() calls
- auto-recovery.ts: 1 roadmap.slices.find() call
- auto-start.ts: 1 state.registry.filter() call

These are belt-and-suspenders guards — the parsers always return arrays,
but crash recovery can encounter partially written or corrupt state files
where the parsers return unexpected shapes.

Fixes #1176
---
 src/resources/extensions/gsd/auto-recovery.ts | 2 +-
 src/resources/extensions/gsd/auto-start.ts    | 2 +-
 src/resources/extensions/gsd/auto.ts          | 6 +++---
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/resources/extensions/gsd/auto-recovery.ts b/src/resources/extensions/gsd/auto-recovery.ts
index e2615b5d2..4b2155921 100644
--- a/src/resources/extensions/gsd/auto-recovery.ts
+++ b/src/resources/extensions/gsd/auto-recovery.ts
@@ -227,7 +227,7 @@ export function verifyExpectedArtifact(unitType: string, unitId: string, base: s
         try {
           const roadmapContent = readFileSync(roadmapFile, "utf-8");
           const roadmap = parseRoadmap(roadmapContent);
-          const slice = roadmap.slices.find(s => s.id === sid);
+          const slice = (roadmap.slices ?? []).find(s => s.id === sid);
           if (slice && !slice.done) return false;
         } catch {
           // Corrupt/unparseable roadmap — fail verification so the unit
diff --git a/src/resources/extensions/gsd/auto-start.ts b/src/resources/extensions/gsd/auto-start.ts
index 6d7570175..1386ba7c1 100644
--- a/src/resources/extensions/gsd/auto-start.ts
+++ b/src/resources/extensions/gsd/auto-start.ts
@@ -415,7 +415,7 @@ export async function bootstrapAutoSession(
   ctx.ui.setStatus("gsd-auto", s.stepMode ? "next" : "auto");
   ctx.ui.setFooter(hideFooter);
   const modeLabel = s.stepMode ? "Step-mode" : "Auto-mode";
-  const pendingCount = state.registry.filter(m => m.status !== 'complete' && m.status !== 'parked').length;
+  const pendingCount = (state.registry ?? []).filter(m => m.status !== 'complete' && m.status !== 'parked').length;
   const scopeMsg = pendingCount > 1
     ? `Will loop through ${pendingCount} milestones.`
     : "Will loop until milestone complete.";
diff --git a/src/resources/extensions/gsd/auto.ts b/src/resources/extensions/gsd/auto.ts
index 4afa7370f..acdcbba22 100644
--- a/src/resources/extensions/gsd/auto.ts
+++ b/src/resources/extensions/gsd/auto.ts
@@ -877,7 +877,7 @@ async function showStepWizard(
     : "previous unit";
 
   if (!mid || state.phase === "complete") {
-    const incomplete = state.registry.filter(m => m.status !== "complete" && m.status !== "parked");
+    const incomplete = (state.registry ?? []).filter(m => m.status !== "complete" && m.status !== "parked");
     if (incomplete.length > 0 && state.phase !== "complete" && state.phase !== "blocked" && state.phase !== "pre-planning") {
       const ids = incomplete.map(m => m.id).join(", ");
       const diag = `basePath=${s.basePath}, milestones=[${state.registry.map(m => `${m.id}:${m.status}`).join(", ")}], phase=${state.phase}`;
@@ -1171,7 +1171,7 @@ async function dispatchNextUnit(
       }
     }
 
-    const pendingIds = state.registry
+    const pendingIds = (state.registry ?? [])
       .filter(m => m.status !== "complete")
       .map(m => m.id);
     pruneQueueOrder(s.basePath, pendingIds);
@@ -1186,7 +1186,7 @@ async function dispatchNextUnit(
       await closeoutUnit(ctx, s.basePath, s.currentUnit.type, s.currentUnit.id, s.currentUnit.startedAt, buildSnapshotOpts(s.currentUnit.type, s.currentUnit.id));
     }
 
-    const incomplete = state.registry.filter(m => m.status !== "complete" && m.status !== "parked");
+    const incomplete = (state.registry ?? []).filter(m => m.status !== "complete" && m.status !== "parked");
     if (incomplete.length === 0) {
       // Genuinely all complete (parked milestones excluded) — merge milestone branch to main before stopping (#962)
       if (s.currentMilestoneId && isInAutoWorktree(s.basePath) && s.originalBasePath) {