[AndyTWF]

Why

Inside ably interactive, pressing Ctrl+C at a [y/n] confirmation (for example push devices remove dev1) exited the whole shell with code 0. It should cancel that one command and return to ably>, the way Ctrl+C at a running command already does.

Root cause

The original suspicion was the shell's readline close handler. It isn't that:

• In wrapper mode that handler exits 42, but the shell exited 0.
• --trace-exit shows no process.exit call.

What actually happens:

1. promptForConfirmation creates its own readline on stdin with no SIGINT listener.
2. With no listener, readline handles Ctrl+C by silently closing the interface, so the rl.question promise never settles.
3. The shell's readline is paused while a command runs, and handleCommand is fire-and-forget. Nothing keeps the event loop alive, so Node drains it and exits with code 0.

Fix

On Ctrl+C, promptForConfirmation now closes its interface and rejects with an InterruptError ("Interrupted by user"). Callers already send rejections through fail(), and the interactive shell's catch block prints the message and redraws the prompt. interactive.ts needed no change.

Rejected alternative: resolving false (treating Ctrl+C as "no"). Several callers carry on when the answer is no: login's "create your first app?", "running the control plane locally?" and "use a different alias?", base-command's "remove invalid key?", and init's global install. For those, Ctrl+C would have meant "no, keep going".

Outside interactive mode, Ctrl+C at a confirm now exits 1 with "Interrupted by user". Before this change it exited 0 silently, for the same drain reason.

Interaction with #474 (DX-1967)

#474 adds forwardSigintToProcess(rl) to this prompt: on Ctrl+C it closes the prompt and re-raises the signal as a process SIGINT. That alone doesn't settle the promise, which is why this bug reproduced with it applied. Whichever PR merges second needs to combine the two:

• Settle the promise (this PR) and still forward the signal (Make Ctrl+C cancel ably accounts login reliably #474).
• Have the prompt reject with Make Ctrl+C cancel ably accounts login reliably #474's InterruptError from sigint-cancellation.ts rather than the class added here.

If two separate classes survive the merge, the prompt's rejection reaches withSigintCancellation's race before the re-raised signal does. Login's instanceof InterruptError check would then miss it, and login would exit 1 instead of 130.

Tests

• New TTY test test/tty/commands/interactive-confirm-sigint.test.ts:
  • runs under node-pty with test mode off;
  • presses Ctrl+C at the push devices remove confirm;
  • asserts "Interrupted by user" followed by ably>;
  • checks the shell then still runs version and exits 42 on exit.
  • It fails on main (the shell exits 0).
• New unit test: the prompt rejects with InterruptError and closes its interface on SIGINT.

Not fixed here

Answering n + Enter at the same prompt in interactive mode echoes nn, and the shell then runs n as a command ("Command n not found"). The paused shell readline still has its line listener attached. That is a separate bug, to be fixed in its own PR.

🤖 Generated with Claude Code

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated
cli-web-cli	Ready	Preview	Oct 21, 2026 9:38am UTC

[claude-code-ably-assistant]

Walkthrough

This PR fixes a bug in ably interactive where pressing Ctrl+C at a [y/n] confirmation prompt (e.g. push devices remove) exits the entire shell with code 0 instead of cancelling the one command and returning to the ably> prompt. The fix adds a SIGINT listener to promptForConfirmation's internal readline interface that closes it and rejects with a new InterruptError, propagating cleanly through the existing error-handling path in the interactive shell. No changes to interactive.ts were required.

Changes

Area	Files	Summary
Utils	src/utils/prompt-confirmation.ts	Added InterruptError class and SIGINT listener that rejects the prompt promise instead of leaving it unsettled
Tests	test/tty/commands/interactive-confirm-sigint.test.ts	New TTY test (node-pty) verifying shell survives Ctrl+C at confirmation and returns to ably>
Tests	test/unit/utils/prompt-confirmation.test.ts	New unit test verifying InterruptError is thrown and readline is closed on SIGINT
Docs	docs/Exit-Codes.md	Documents that Ctrl+C at a y/n prompt cancels the command and returns to prompt
Docs	docs/Project-Structure.md	Updated directory comment for test/tty/commands/ to reflect the new test

Review Notes

• Merge interaction with PR Make Ctrl+C cancel ably accounts login reliably #474: The PR description explicitly calls out that whichever of Make Ctrl+C cancel ably accounts login reliably #474 and this PR merges second must combine both approaches — this PR's promise rejection and Make Ctrl+C cancel ably accounts login reliably #474's forwardSigintToProcess(rl). The merged result should use Make Ctrl+C cancel ably accounts login reliably #474's InterruptError from sigint-cancellation.ts rather than the one introduced here. This coordination is required to avoid conflicts.
• Exported InterruptError: The class is exported from prompt-confirmation.ts. If Make Ctrl+C cancel ably accounts login reliably #474 is merged first and provides its own canonical InterruptError, callers will need to import from the new location and this PR's class should be removed.
• Known unrelated bug: Answering n + Enter at the same prompt echoes nn and runs n as a command — explicitly noted as out of scope for this PR.
• TTY test coverage: The confirmation-SIGINT path is covered by a TTY test (requires node-pty) plus a unit test. CI environments that skip test:tty will not run the end-to-end scenario.