fix(cursor): catch EOF terminal budget overflow

[luvs01]

Summary

• route exceptions thrown by Cursor clean-EOF finalization through the same terminal failure handler used for drain failures
• prevent a translator-budget exception raised inside the fulfilled continuation from becoming an unhandled rejection that can leave the turn unsettled
• preserve the existing EOF classification, single-shot settler, and idempotent backlog-lease cleanup contracts

Exact base: 03735eca62398c55056d4595145561aecc444e91
Exact head: deacd53f79e1ff4eaea6baa28a4d849809e8d673

Verification

• Bun 1.4 Cursor hardening — 41/41 passed
• Bun 1.4 adjacent EOF terminal and live transport — 23/23 passed
• Bun 1.4 typecheck — passed
• privacy scan and git diff --check — passed
• independent current-diff review — no findings

The full repository suite was not duplicated locally; maintained cross-platform CI remains the merge gate. No GUI, configuration, credential, or protocol surface is changed.

Checklist

• Scope stays focused and avoids unrelated cleanup.
• Docs or release notes were updated when needed; this internal error-routing fix adds no user-facing workflow or configuration.
• Failure, terminal-settlement, and retained-budget cleanup behavior were reviewed for unsafe defaults and residual ownership.

Review readiness checklist

• All CI tests are green on my local testing.
• I pushed my PR to the latest dev commit.
• I resolved all correct Codex and CodeRabbit findings.
• My PR is ready for review.

[github-actions]

✅ Deterministic PR hygiene checks passed.

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ℹ️ Recent review info

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Run ID: 950c935d-a575-4917-80c3-053ff9c03a90

📥 Commits

Reviewing files that changed from the base of the PR and between 03735ec and deacd53.

📒 Files selected for processing (2)

• src/adapters/cursor/live-transport.ts
• tests/cursor-hardening.test.ts

Included review availability: Your plan provides up to 10 included reviews per hour; 8 remain after this review.

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📝 Walkthrough

Walkthrough

Changes

Cursor stream hardening

Layer / File(s)	Summary
Stream finalization and budget regression src/adapters/cursor/live-transport.ts, tests/cursor-hardening.test.ts	The stream-end promise routes failures through chained .catch(...) handling and failAndClear at line 1132. The new test sends repeated text frames through clean EOF synthesis, verifies TranslatorBudgetExceededError with translation_buffer_limit, and confirms that no buffered bytes remain at lines 626–678.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to deacd

This localized fix routes EOF finalization failures through the existing terminal failure path without changing user-facing configuration or protocol behavior. No actionable merge-blocking risk remains after normal checks and review.

Suggested reviewers: lidge-j

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 2 files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the fix for Cursor EOF terminal budget overflow, which is the main change in the pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[github-actions]

✅ READY

• all PR quality gates passed; the review readiness checklist is complete.

Review readiness checklist

• ✅ All CI tests are green on my local testing.
• ✅ I pushed my PR to the latest dev commit.
• ✅ I resolved all correct Codex and CodeRabbit findings.
• ✅ My PR is ready for review.

✅ 4/4 boxes ticked.

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Maintainers: @lidge-jun @Ingwannu

[lidge-jun]

리뷰 · 우선순위 63 / 80

구멍은 Promise 2인자임. 지금 dev src/adapters/cursor/live-transport.ts onStreamEnd가 drain 루프를 .then(성공, 실패)로 붙임. 프레임 체인은 이미 .catch로 failAndClear를 탐 (:1009-1011). EOF 최종화만 2인자라서 onFulfilled 안에서 터진 예외는 거기로 안 감. finalizeTurnEvents / push / settleFinish가 TranslatorBudgetExceededError 내면 언핸들드 리젝션이고 턴은 안 끝남. 백로그 리스도 안 풀릴 수 있음.

이 PR은 그 .then을 .catch로 바꿈. 한 줄. 성공 콜백에서 난 예외도 failAndClear로 감. failAndClear가 releaseBacklogLease 다음에 세틀러로 들어가니 아이덴포턴트 정산 계약은 그대로임. 분류/싱글샷 세틀러/리스 정리는 안 건드림. 방향 맞음.

테스트가 maxTurnBytes: 1_000에 텍스트 프레임 37개 + clean Connect EOF를 넣음. TranslatorBudgetExceededError / translation_buffer_limit 나오고 budget.snapshot().currentBytes가 0임. 예외만 잡고 바이트를 안 풀면 실패하는 케이스임. ㅋㅋ 그 어서션이 핵심임.

#2195 터미널 가드 델타랑 다른 선임. 그건 머지됨. 이건 EOF 합성 경로의 캐치 구멍임. #2210 스톨 워치독이랑도 다름. 브릿지 idle이 아니라 트랜스포트 버짓임. #2212 composer-2.5 continuation이랑 안 섞을 것. types.ts/config.ts 스플릿 안 씹힘. live-transport.ts랑 테스트만임. base가 지금 HEAD 03735eca6랑 같음. 리베이스 필요 없음. 닫을 중복 아님.

review-ready고 draft 아님. Cursor hardening 41, adjacent EOF 23, typecheck 그린이라 했음. 전체 스위트는 로컬에서 안 돌렸다 함. CI가 머지 게이트임. 2.28 블로커는 아님. 그래도 턴이 안 끝나는 구멍이라 점수는 높음.

해결방안: CI 그린이면 dev 머지. .then(ok, err)를 이 파일에 다시 넣지 말 것. 프레임 체인처럼 .catch만 쓸 것. 버짓 초과 실패 뒤에 currentBytes === 0 어서션 유지.

이 댓글은 grok-bot이 작성했습니다

[Ingwannu]

Reviewed exact head deacd53. The EOF finalization rejection now reaches the existing failAndClear path, and the regression covers both the translation_buffer_limit failure and released budget bytes. No unresolved threads remain and the exact-head CI rollup is green. Approved for dev.