WSL port 7/7: bind the quit chord that WSL actually sends

[jainal09]

Stacked on #12. Found by pressing the key — which is exactly what checkpoint 5
said would be needed, because nothing automated can reach this.

What was wrong

Ctrl+Shift+Q did nothing on WSL.

Windows Terminal 1.24 is new enough to speak CSI-u and does not negotiate it
with nvim. So the chord arrives as the legacy 0x11 — plain <C-q> — and the
<C-S-q> mapping is never reached. The documented way out of the editor did not
exist on WSL, leaving :qa! — the one thing that whole section of the config
was written to stop being necessary.

Why no test caught it

• suite_quit.sh writes ESC[113;6u straight onto the pty, so it passes on
  a terminal where the chord could never arrive.
• demo.sh --check cannot send CSI-u over --remote-send at all (checkpoint 4).
• vim.g.termfeatures is nil even in a real TUI on nvim 0.12, so there is no
  runtime signal to detect CSI-u from Lua either.

This one genuinely required a human to press it.

The fix

Bind what actually arrives. This is not a second key to learn — you press
Ctrl+Shift+Q, exactly as documented, and <C-q> is what nvim is handed.

Insert only, and gated on WSL, because both halves cost something:

• normal mode keeps Ctrl+Q as visual block — it is the only way to ask for
  one, and drill's premise is that you are in insert anyway
• in insert, vanilla <C-q> is literal-insert, the twin of <C-v>. In a
  Python scratchpad where <C-v> is already paste that is close to unreachable,
  and a quit prompt defaulting to Cancel is the better use of the key. But it is
  a real vim behaviour, so nowhere but WSL loses it.

Verification — both branches, forced each way

On WSL:

insert  <C-q>   : -> quit_drill (callback)
normal  <C-q>   : <C-V>
insert  <C-S-q> : -> quit_drill (callback)
insert  <C-v>   : <C-R><C-O>+

Forced non-WSL — what a Mac sees:

insert  <C-q>   : UNMAPPED (vanilla literal-insert)
normal  <C-q>   : <C-V>
insert  <C-S-q> : -> quit_drill
insert  <C-v>   : <C-R><C-O>+

Byte-for-byte the old behaviour off WSL.

Suite: 556/556, ALL SUITES PASSED. Every <C-q> case in the suite is
normal-mode (suite_options.sh asserts it maps to <C-V>; suite_comment.sh's
visual-block case is --start normal), so none of them touch the new binding.

The WSL probe is hoisted to one IS_WSL near the top, since the clipboard
fallback asks the same question.

🤖 Generated with Claude Code

https://claude.ai/code/session_01WveBqAyhoM49p9gWfwBDBx

---

Summary by cubic

Make the quit chord work on WSL by binding what Windows Terminal actually sends. On WSL, insert- and terminal‑mode <C-q> opens the quit prompt; normal‑mode <C-q> stays visual block. Off WSL, behavior is unchanged.

• Bug Fixes

  • WSL: map insert- and terminal‑mode <C-q> to the quit prompt because Windows Terminal 1.24 doesn’t negotiate CSI‑u with nvim and sends 0x11; lets you quit from inside the REPL while keeping normal‑mode <C-q> for visual block.
  • Docs: clarify the IS_WSL gate (env, not protocol), the normal‑mode gap on non‑CSI‑u terminals, terminal‑mode quit, the insert‑mode literal‑insert trade‑off, and retract the earlier --remote-send collapse claim.

• Refactors

  • Hoisted a single IS_WSL probe and applied the fallback in insert and terminal modes.
  • Tests: add suite_options.sh checks to ensure the <C-q> fallback binds only on WSL (i/t) and does not leak to Linux CI.
  • Comments: note readline binds ^Q to quoted‑insert; the fallback trades it for quit, with ^V still providing quoted‑insert.

^{Written for commit 69b5867. Summary will update on new commits.}

Summary by CodeRabbit

• New Features
  • Added WSL support for terminals that send Ctrl+Shift+Q as Ctrl+Q.
  • In insert and terminal modes, the shortcut now opens the quit prompt; normal-mode Ctrl+Q retains visual-block selection.
  • Terminals supporting CSI-u continue to use the dedicated Ctrl+Shift+Q behavior.
• Documentation
  • Clarified terminal compatibility, WSL-specific key behavior, quit instructions, and automated testing limitations.

Greptile Summary

The PR makes the documented quit chord work when Windows Terminal sends its legacy <C-q> encoding under WSL.

• Adds a WSL-gated <C-q> fallback in insert and terminal modes while preserving normal-mode visual block.
• Documents the CSI-u limitation and intentional keybinding trade-offs.
• Adds platform-sensitive assertions that the fallback is present only on WSL.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains; the current WSL-gated mapping includes both insert and terminal modes, so the previously reported missing REPL fallback is fixed.

Important Files Changed

Filename	Overview
nvimrc.lua	Adds the missing terminal-mode fallback alongside insert mode, fully addressing the previous review thread while preserving normal-mode <C-q>.
tests/suite_options.sh	Verifies that callback mappings exist in insert and terminal modes exactly when the shared WSL detection is true.
KEYS.md	Documents the non-CSI-u normal-mode limitation and the WSL-specific fallback behavior.
docs/wsl.md	Explains the terminal encoding behavior, affected modes, and deliberate loss of literal insert on WSL.
TODO.md	Updates checkpoint evidence and records the manually verified WSL key-encoding behavior.

_{Reviews (25): Last reviewed commit: "Test the WSL quit fallback, and stop cal..." | Re-trigger Greptile}

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[jainal09]

@coderabbitai review

[coderabbitai]

⚠️ Action not completed

Review rate limited.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[coderabbitai]

📝 Walkthrough

Walkthrough

The change adds a WSL-only <C-q> fallback for insert and terminal modes, preserves normal-mode visual-block selection, and updates key documentation and validation gates for terminals without CSI-u support.

Changes

WSL Ctrl+Shift+Q fallback

Layer / File(s)	Summary
WSL fallback mapping nvimrc.lua, TODO.md	WSL maps legacy <C-q> input to quit_drill in insert and terminal modes. Normal mode remains unchanged.
Mode-specific behavior documentation KEYS.md, docs/wsl.md	The documentation describes Windows Terminal encoding, CSI-u conditions, prompt behavior, and normal-mode limitations.
Validation and process checks TODO.md	Validation gates cover installer, clipboard, timer, CI, demo, and measured WSL behavior. Timer matching now uses executable and argument checks.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Sequence Diagram(s)

sequenceDiagram
  participant WindowsTerminal
  participant Neovim
  participant quit_drill
  participant confirm
  WindowsTerminal->>Neovim: Send Ctrl+Shift+Q as legacy <C-q>
  Neovim->>quit_drill: Invoke mapping in insert or terminal mode
  quit_drill->>confirm: Show quit prompt
  confirm-->>Neovim: Return quit decision

Loading

🚥 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.
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 WSL-specific quit-chord binding added by the pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch wsl/07-quit-legacy

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[cubic-dev-ai]

All reported issues were addressed across 4 files

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[jainal09]

@greptileai review

[jainal09]

@coderabbitai review

[coderabbitai]

✅ Action performed

Review finished.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[coderabbitai]

Actionable comments posted: 2

🧹 Nitpick comments (2)

nvimrc.lua (2)

1274-1280: 📐 Maintainability & Code Quality | 🔵 Trivial | ⚡ Quick win

Change INSERT ONLY to match the terminal-mode mapping.

The mapping includes terminal mode t. Change the heading to INSERT AND TERMINAL ONLY so the comment matches the implementation.

Proposed fix

--- INSERT ONLY, and gated on WSL, because both halves cost something:
+-- INSERT AND TERMINAL ONLY, and gated on WSL, because both halves cost something:

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@nvimrc.lua` around lines 1274 - 1280, Update the comment heading above the
Ctrl+Q mapping from “INSERT ONLY” to “INSERT AND TERMINAL ONLY” so it accurately
reflects the terminal-mode mapping.

---

1289-1291: 📐 Maintainability & Code Quality | 🔵 Trivial | 🏗️ Heavy lift

Add PTY coverage for raw legacy 0x11.

The current PTY cases only send CSQ = "\x1b[113;6u", so they do not cover the WSL <C-q> fallback. Add insert and terminal-mode cases that send raw \x11 after disabling ixon, and assert the prompt plus Cancel/Quit behavior.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@nvimrc.lua` around lines 1289 - 1291, Add PTY coverage alongside the existing
CSQ cases for the WSL mapping in the <C-q> path: in both insert and terminal
modes, disable ixon, send raw 0x11, and assert the expected prompt followed by
the appropriate Cancel/Quit behavior.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@docs/wsl.md`:
- Around line 93-109: Update the WSL behavior documentation around the
nvimrc.lua keybinding description to include terminal mode alongside insert and
normal modes, and revise the consequences text so bare Ctrl+Q is documented as
quitting from both insert and terminal modes. Preserve the existing CSI-u and
non-WSL behavior details.

In `@TODO.md`:
- Around line 78-87: Rename the socket-check output and related gate wording
around the Ctrl+Shift+Q case to describe Neovim key-notation mapping or prompt
behavior, not CSI-u delivery. Keep the check unconditional and preserve the
existing test behavior; only remove the misleading “CSI-u” terminology from the
relevant labels.

---

Nitpick comments:
In `@nvimrc.lua`:
- Around line 1274-1280: Update the comment heading above the Ctrl+Q mapping
from “INSERT ONLY” to “INSERT AND TERMINAL ONLY” so it accurately reflects the
terminal-mode mapping.
- Around line 1289-1291: Add PTY coverage alongside the existing CSQ cases for
the WSL mapping in the <C-q> path: in both insert and terminal modes, disable
ixon, send raw 0x11, and assert the expected prompt followed by the appropriate
Cancel/Quit behavior.

🪄 Autofix

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 1c4dd2dc-145b-47e5-a62a-ea4a9c8b6528

📥 Commits

Reviewing files that changed from the base of the PR and between ee56816 and 0bcddf8.

📒 Files selected for processing (4)

• KEYS.md
• TODO.md
• docs/wsl.md
• nvimrc.lua

[cubic-dev-ai]

All reported issues were addressed across 4 files (changes from recent commits).

<sub>Tip: Review your code locally with the cubic CLI to iterate faster.

Re-trigger cubic</sub>

[codescene-access]

No application code in the PR — skipped Code Health checks.

See analysis details in CodeScene

Quality Gate Profile: Clean Code Collective
Install CodeScene MCP: safeguard and uplift AI-generated code. Catch issues early with our IDE extension and CLI tool.