fix(cli): exit cleanly on terminal hangup (read EIO) during interactive prompts

[rayhanadev]

Why

Catches the Error: read EIO crash reported in Sentry (REACT-DOCTOR-S).

The only thing that reads stdin is the interactive prompts UI (e.g. the multiselect "Select projects" prompt in a monorepo), which opens the TTY in raw mode and never attaches an 'error' listener. When the terminal/PTY backing that prompt goes away mid-read — closing the tab, the parent shell exiting, a dropped SSH/tmux/screen session, or the machine sleeping/waking — the next read() returns EIO. With no listener on process.stdin, Node escalates that stream error into a fatal uncaught exception, which the Sentry onuncaughtexception integration reports as a crash (level: fatal, handled: no). The stack is pure Node internals (TTY.onStreamRead), confirming an environmental terminal teardown rather than a logic bug.

Before (no stdin error listener — an environmental hangup crashes and is reported to Sentry):

process.on("SIGINT", exitGracefully);
process.on("SIGTERM", exitGracefully);
unrefStdin();
// stdout EPIPE is guarded, but stdin has no 'error' handler →
// `read EIO` becomes a fatal uncaught exception.

After (stdin is guarded; a hangup exits cleanly, genuine errors still report):

unrefStdin();
guardStdin(); // process.stdin.on("error", …): exit 129 on EIO/ENXIO, re-throw otherwise

What changed

• Added guardStdin() (src/cli/utils/guard-stdin.ts), armed at startup in cli/index.ts next to unrefStdin() and the existing stdout EPIPE guard it mirrors.
• On a terminal-hangup errno (EIO/ENXIO) the CLI exits cleanly with code 129 (POSIX 128 + SIGHUP), so the run ends like an interruption instead of a crash.
• Re-throws any other stdin error, so genuine stdin failures keep funneling to the crash reporter exactly as before.
• Added TERMINAL_HANGUP_EXIT_CODE = 129 to constants.ts, alongside the existing SIGINT_EXIT_CODE.
• Adds tests for: exits with 129 on EIO/ENXIO, re-throws (never exits) on EPIPE/EACCES/no-code, and that guardStdin() registers the handler.

Eval results

RDE not run — this is a CLI stdin/teardown fix, not a lint rule, so the rule-eval harness doesn't apply.

Test plan

• pnpm test (react-doctor) — 170 passed, incl. new tests/guard-stdin.test.ts
• pnpm typecheck — clean
• pnpm format:check — clean; pnpm lint — clean (only pre-existing fixture warnings)

Made with Cursor

---

Note

Low Risk
Small, startup-only stdin listener with narrow errno handling; non-hangup errors unchanged; covered by unit tests.

Overview
Adds a startup stdin error guard (parallel to the existing stdout EPIPE handler) so losing the TTY while an interactive prompts read is in progress no longer becomes a fatal uncaught read EIO / Sentry crash.

guardStdin() wires process.stdin 'error' to handleStdinError: EIO / ENXIO → process.exit(129) via new TERMINAL_HANGUP_EXIT_CODE; any other code is re-thrown so real stdin failures still hit the crash reporter. guardStdin() is invoked from cli/index.ts right after unrefStdin(), before commands run. Tests cover hangup vs non-hangup errno and listener registration; changeset documents the patch.

^{Reviewed by Cursor Bugbot for commit 134f305. Bugbot is set up for automated code reviews on this repo. Configure here.}

[react-doctor-evals]

✅ Parity OK — no diagnostic differences.

Baseline: main · This PR: ray/f762b202 (134f305)

ℹ️ Re-run this parity check by commenting /rde parity on this PR.

_{trace 12b4a050eaff6d27ba2967eb59c19135 · rde}

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

View in Devin Review to see 2 additional findings.

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/eslint-plugin-react-doctor@650

npm i https://pkg.pr.new/oxlint-plugin-react-doctor@650

npm i https://pkg.pr.new/react-doctor@650

commit: 134f305

[github-actions]

React Doctor found 5 files changed in this pull request, but none matched the files covered by its enabled checks.

Scope: 5 files changed on ray/f762b202 vs. main.

View workflow run

Generated by React Doctor. Questions? Contact founders@million.dev.