Handle terminal exit writes and auto-close exited terminal drawer

[juliusmarminge]

Summary

• Ignore terminal write calls when a session has already exited, instead of throwing an error.
• Add a server test to verify trailing writes after process exit are safely ignored.
• Update terminal drawer behavior to auto-close an exited terminal session in the UI.
• Prevent duplicate exit handling in the terminal viewport by guarding and resetting exit state on restart.

Testing

• Added unit test: apps/server/src/terminal/Layers/Manager.test.ts (ignores trailing writes after terminal exit).
• Not run: full project lint script.
• Not run: full test suite.

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Note

Medium Risk
Medium risk because it changes terminal I/O error handling and introduces new UI side effects (auto-closing) on exited events; could mask legitimate client/server state bugs or close tabs unexpectedly if exit events are misfired/duplicated.

Overview
Prevents server-side terminal write calls from throwing after a session has already exited by returning early when status === "exited".

Adds a unit test ensuring post-exit writes are ignored, and updates the web ThreadTerminalDrawer/TerminalViewport to auto-close a terminal tab when it receives an exited event, with guards to avoid duplicate exit handling and to reset the exit guard on restart.

^{Written by Cursor Bugbot for commit e6fd90d. This will update automatically on new commits. Configure here.}

Note

Ignore writes after terminal exit in TerminalManagerRuntime.write and auto-close ThreadTerminalDrawer when a session exits

Update server write behavior to no-op on exited sessions and add client-side auto-close on terminal exited events. Add a test covering trailing writes after process exit in Manager.test.ts, adjust TerminalManagerRuntime.write in Manager.ts, and wire onSessionExited to close drawers in ThreadTerminalDrawer.tsx.

📍Where to Start

Start with TerminalManagerRuntime.write in Manager.ts, then review the exit handling flow in ThreadTerminalDrawer.tsx, and validate behavior via the new test in Manager.test.ts.

^{Macroscope summarized e6fd90d.}

Summary by CodeRabbit

• Bug Fixes

  • Terminal sessions now gracefully handle write attempts after exit, preventing errors and ensuring clean termination.

• New Features

  • Terminals automatically close when the session exits, improving cleanup and user experience.

[coderabbitai]

📝 Walkthrough

Walkthrough

These changes implement terminal session exit handling across frontend and backend. The backend prevents write errors when a session has exited, a new test validates this behavior, and the frontend threads an exit callback through terminal components to trigger drawer closure.

Changes

Cohort / File(s)	Summary
Backend Terminal Manager apps/server/src/terminal/Layers/Manager.ts, apps/server/src/terminal/Layers/Manager.test.ts	Added early return in Manager.write when session status is "exited" to silently ignore trailing writes post-termination. New test validates that write attempts after terminal exit resolve to undefined without side effects.
Frontend Session Exit Handling apps/web/src/components/ThreadTerminalDrawer.tsx	Introduced onSessionExited callback prop to TerminalViewport, threaded from ThreadTerminalDrawer. Coordinates single-time exit handling via hasHandledExitRef, resets on terminal restart events, and triggers drawer closure asynchronously when session exits.

Sequence Diagram(s)

sequenceDiagram
    participant Drawer as ThreadTerminalDrawer
    participant Viewport as TerminalViewport
    participant Terminal as Terminal Process
    participant Manager as Manager

    Terminal->>Manager: emit "exited" event
    Manager->>Viewport: terminal "exited" event
    Viewport->>Viewport: check hasHandledExitRef
    Note over Viewport: Set hasHandledExitRef = true
    Viewport->>Viewport: setTimeout(() => onSessionExited(), 0)
    Viewport->>Drawer: onSessionExited callback
    Drawer->>Drawer: onCloseTerminal(terminalId)

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Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the two main changes: handling terminal exit writes (in Manager.ts) and auto-closing the terminal drawer (in ThreadTerminalDrawer.tsx).
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

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✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch codething/0cbde587

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[coderabbitai]

🧹 Nitpick comments (1)

apps/web/src/components/ThreadTerminalDrawer.tsx (1)

347-353: Guard deferred close callback after unmount.

The zero-delay callback can still fire after cleanup. Add a disposed check before invoking onSessionExitedRef.current() to avoid stale close calls.

Suggested patch

         hasHandledExitRef.current = true;
         window.setTimeout(() => {
+          if (disposed) return;
           onSessionExitedRef.current();
         }, 0);

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@apps/web/src/components/ThreadTerminalDrawer.tsx` around lines 347 - 353, The
deferred zero-delay callback can run after the component unmounts; update the
timeout callback in ThreadTerminalDrawer so it checks a disposal flag before
calling onSessionExitedRef.current(): add or reuse a disposedRef (e.g., const
disposedRef = useRef(false) and set disposedRef.current = true in the
cleanup/unmount), then change the setTimeout handler to if (!disposedRef.current
&& !hasHandledExitRef.current) { hasHandledExitRef.current = true;
onSessionExitedRef.current(); } (or at minimum check disposedRef.current before
invoking onSessionExitedRef.current()) to avoid stale close calls.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@apps/web/src/components/ThreadTerminalDrawer.tsx`:
- Around line 347-353: The deferred zero-delay callback can run after the
component unmounts; update the timeout callback in ThreadTerminalDrawer so it
checks a disposal flag before calling onSessionExitedRef.current(): add or reuse
a disposedRef (e.g., const disposedRef = useRef(false) and set
disposedRef.current = true in the cleanup/unmount), then change the setTimeout
handler to if (!disposedRef.current && !hasHandledExitRef.current) {
hasHandledExitRef.current = true; onSessionExitedRef.current(); } (or at minimum
check disposedRef.current before invoking onSessionExitedRef.current()) to avoid
stale close calls.

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ℹ️ Review info

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between e6c5a4a and dd5b985.

📒 Files selected for processing (3)

• apps/server/src/terminal/Layers/Manager.test.ts
• apps/server/src/terminal/Layers/Manager.ts
• apps/web/src/components/ThreadTerminalDrawer.tsx