Adopt LOC gate from lean-ctx (#660)

[getappz]

Auto-opened on item done for 019f6f54-413f-78f1-afd2-d17f3b842a8b.

Summary by CodeRabbit

• Chores
  • Added an automated Rust source line-count enforcement check to keep files within set size limits.
  • Included an allowlist for legacy Rust files with a higher threshold, ensuring they remain eligible.
  • The check fails when limits are exceeded and reports success when all files comply.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 46c314e and 6242c52.

📒 Files selected for processing (1)

• scripts/loc-gate.sh

🚧 Files skipped from review as they are similar to previous changes (1)

• scripts/loc-gate.sh

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📝 Walkthrough

Walkthrough

Adds scripts/loc-gate.sh, which scans repository Rust files, enforces standard and frozen line limits, validates the legacy allowlist, and exits nonzero on violations.

Changes

Rust LOC gate

Layer / File(s)	Summary
Rust file LOC validation scripts/loc-gate.sh	Scans .rs files excluding target/, applies limits for regular and allowlisted files, verifies allowlisted entries, and prints failures or LOC gate OK.

Estimated code review effort: 2 (Simple) | ~10 minutes

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description is a placeholder and omits the required Summary, Test plan, and Notes for reviewers sections.	Replace the placeholder with the template sections and briefly describe the change, tests run, risk areas, and backwards compatibility.
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 (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: adopting the LOC gate from lean-ctx.
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

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch task/150

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[coderabbitai]

Actionable comments posted: 2

🤖 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 `@scripts/loc-gate.sh`:
- Around line 24-35: Normalize each path emitted by find before passing it to
is_allowed and before using it in related checks or messages, removing the
leading ./ so it matches the relative paths stored in ALLOWLIST. Update the loop
around is_allowed in the loc-gate script while preserving the existing frozen
and regular limit behavior.
- Around line 24-35: The Rust file traversal in the LOC gate must fail closed
when find encounters an error. Update the loop around the find pipeline to
capture and validate find’s exit status, returning a failure instead of
reporting success when traversal fails; also use null-delimited output with read
-d '' to preserve paths safely.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

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

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: 2b534e38-d7c3-48a9-81be-82cbf974fa89

📥 Commits

Reviewing files that changed from the base of the PR and between 2b58ffd and 46c314e.

📒 Files selected for processing (1)

• scripts/loc-gate.sh