fix(wsl): preserve single-letter POSIX terminal cwd

[OrcaWin]

Summary

• Preserve exact absolute POSIX cwd paths, including /a and /c, when the selected Windows runtime is WSL.
• Fall back to the workspace root only after WSL proves the requested cwd is missing and the root exists.
• Keep native/MSYS launch semantics aligned, avoid probes for SSH and successful stable-pane adoption, and route fresh spawns through daemon protocol v33 while preserving older daemon-owned sessions.

This is the latest-main release audit follow-up for historical PR #13420.

Linear: STA-3925

Screenshots

No visual change.

Testing

• pnpm lint
• pnpm typecheck
• pnpm test
• pnpm build
• Added or updated high-quality tests that would catch regressions, or explained why tests were not needed

Completed proportional validation:

• Deterministic oracle on final origin/main: baseline RED, candidate GREEN, in-memory revert RED for both /a and /c.
• Physical Windows 2 / WSL2 (Ubuntu-24.04) proof: exact /a and /c; missing wsl.exe --cd /q warns, returns /, and exits 0; inode-guarded cleanup verified.
• Native Windows: /a -> C:\a, /c -> C:\c; Git Bash/MSYS: /a -> A:\, /c -> C:\.
• Focused IPC/provider/daemon/protocol tests, plus SSH and folder-workspace cwd tests.
• Node typecheck; Oxlint default/type-aware/React Doctor with denied warnings; formatting; max-lines ratchet; diff check.

AI Review Report

Fresh adversarial, performance, and internal reviews are clean. Review explicitly covered macOS, Linux, and Windows path/shell behavior; WSL vs native/MSYS authority; SSH and folder workspaces; stable-pane probe cost; daemon generation skew; test quality; and Electron main/daemon boundaries.

Review findings addressed:

• Removed caller-asserted daemon cwd prevalidation and retained daemon-side validation.
• Added daemon protocol v33 so a surviving v32 daemon cannot reinterpret fresh /a or /c spawns.
• Deferred WSL probes until stable-pane adoption fails and pinned SSH zero-probe behavior.
• Aligned non-WSL MSYS existence checks with native launch normalization.
• Added mismatch, daemon /a//c, timing attribution, and local-build compatibility coverage.

Security Audit

Reviewed cwd input handling, path normalization, WSL command construction/quoting, IPC/provider trust boundaries, SSH isolation, and daemon protocol skew. The exact-path prevalidation hint remains in-process only and must equal the provider’s independently resolved path; it is not sent over daemon or SSH RPC. No auth, secret, dependency, or new external-command surface was added.

Notes

• Daemon v1-v32 sessions remain attachable; fresh sessions route to v33.
• Full local pty.test.ts has three unchanged Windows host-coupling failures, and full pty-subprocess.test.ts has two unchanged default-distro expectation failures. Focused changed contracts pass.
• The local cross-version harness cannot extract its release checkout through Git Bash when given a native Windows staging path; the Linux CI cross-version lane is the authoritative run.
• Do not merge as part of this audit.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 20204f5c-44c5-4cea-acff-a223aaf1df05

📥 Commits

Reviewing files that changed from the base of the PR and between 97ebfd9 and 92d6d60.

📒 Files selected for processing (14)

• src/main/daemon/daemon-foreground-confirmation-protocol.test.ts
• src/main/daemon/daemon-protocol-version.test.ts
• src/main/daemon/daemon-protocol-version.ts
• src/main/daemon/daemon-pty-router.test.ts
• src/main/daemon/pty-subprocess.test.ts
• src/main/ipc/pty.test.ts
• src/main/ipc/pty.ts
• src/main/providers/local-pty-provider.test.ts
• src/main/providers/local-pty-provider.ts
• src/main/providers/pty-provider-contract.ts
• src/main/providers/windows-shell-args.test.ts
• src/main/providers/windows-shell-args.ts
• src/shared/local-build-compatibility-contract.json
• src/shared/local-build-compatibility-contract.ts

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📝 Walkthrough

Walkthrough

The daemon protocol advances from version 32 to 33 and adds a WSL POSIX CWD protocol gate. Legacy protocol version 32 remains supported, including session routing. PTY startup defers fresh-session CWD validation until after stable-pane adoption. Local spawns validate Windows and WSL paths, record validated CWD data, and pass matching prevalidation evidence to providers. Tests cover WSL, Windows, Git Bash, SSH, fallback, and adopted-pane scenarios.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the primary user-visible change: preserving single-letter POSIX terminal working directories in WSL.
Description check	✅ Passed	The description includes all required sections and provides clear change details, validation results, review coverage, security assessment, and platform notes.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
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.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

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[OrcaWin]

@coderabbitai full review

[coderabbitai]

✅ Action performed

Full review finished.

[coderabbitai]

Actionable comments posted: 1

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 34225254-a3e5-4c03-b981-ada1bd67c78a

📥 Commits

Reviewing files that changed from the base of the PR and between 97ebfd9 and ee32bed.

📒 Files selected for processing (14)

• src/main/daemon/daemon-foreground-confirmation-protocol.test.ts
• src/main/daemon/daemon-protocol-version.test.ts
• src/main/daemon/daemon-protocol-version.ts
• src/main/daemon/daemon-pty-router.test.ts
• src/main/daemon/pty-subprocess.test.ts
• src/main/ipc/pty.test.ts
• src/main/ipc/pty.ts
• src/main/providers/local-pty-provider.test.ts
• src/main/providers/local-pty-provider.ts
• src/main/providers/pty-provider-contract.ts
• src/main/providers/windows-shell-args.test.ts
• src/main/providers/windows-shell-args.ts
• src/shared/local-build-compatibility-contract.json
• src/shared/local-build-compatibility-contract.ts

[OrcaWin]

@coderabbitai full review

[coderabbitai]

✅ Action performed

Full review finished.