Use patchSession to avoid race conditions in review flag updates

The load-modify-save pattern could overwrite concurrent state changes.
patchSession does an atomic read-patch-write, and the list command now
re-checks activity before clearing stale flags to avoid racing with a
review that just started.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/commands/list.ts

@@ -59,15 +59,11 @@ export async function action(opts: { json?: boolean }) {
   )
   const statuses = Object.fromEntries(statusEntries)
 
-  // Batch self-heal stale in_review flags — reload fresh state to avoid overwriting concurrent changes
-  if (staleReviewSessions.length > 0) {
-    for (const s of staleReviewSessions) s.in_review = false
-    const fresh = await state.load(root).catch(() => null)
-    if (fresh) {
+  // Self-heal stale in_review flags — re-check activity to avoid racing with a concurrent review start
   for (const s of staleReviewSessions) {
-        if (fresh.sessions[s.branch]) fresh.sessions[s.branch].in_review = false
-      }
-      await state.save(root, fresh).catch(() => {})
+    const stillActive = await vm.isClaudeActive(s.worktree, s.branch)
+    if (!stillActive) {
+      await state.patchSession(root, s.branch, { in_review: false }).catch(() => {})
     }
   }
 

src/commands/review.ts

@@ -68,14 +68,12 @@ Your thoughts, in brief.
 `
   if (extra) prompt += "\n\n" + extra
 
-  session.in_review = true
-  await state.setSession(root, session)
+  await state.patchSession(root, session.branch, { in_review: true })
 
   try {
     if (opts.print) {
       spin.text = "Running review…"
       const result = await vm.claude(session.worktree, { print: prompt })
-      spin.stop()
       if (result.output) process.stdout.write(result.output + "\n")
     } else {
       spin.succeed("Session ready")
@@ -83,13 +81,9 @@ Your thoughts, in brief.
     }
   } finally {
     spin.stop()
+    // Clear review flag before saveChanges to minimize the race window
+    await state.patchSession(root, session.branch, { in_review: false }).catch(() => {})
     // Save worktree changes only in interactive mode
-    if (!opts.print) await saveChanges(session.worktree, session.branch).catch(() => {})
-    // Patch only in_review on fresh state to avoid overwriting concurrent changes
-    const current = await state.load(root).catch(() => null)
-    if (current?.sessions[session.branch]) {
-      current.sessions[session.branch].in_review = false
-      await state.save(root, current).catch(() => {})
-    }
+    if (!opts.print) await saveChanges(session.worktree, session.branch)
   }
 }

src/state.ts

@@ -47,6 +47,14 @@ export async function setSession(repoRoot: string, session: Session): Promise<vo
   await save(repoRoot, state)
 }
 
+export async function patchSession(repoRoot: string, branch: string, patch: Partial<Session>): Promise<void> {
+  const state = await load(repoRoot)
+  if (state.sessions[branch]) {
+    Object.assign(state.sessions[branch], patch)
+    await save(repoRoot, state)
+  }
+}
+
 export async function removeSession(repoRoot: string, branch: string): Promise<void> {
   const state = await load(repoRoot)
   delete state.sessions[branch]