linter

Rules enforced on every PR. CI fails on any violation.

Standard Rust tooling

Clippy configuration

clippy.toml:

avoid-breaking-exported-api = false
msrv = "1.82"

Lint levels in src/lib.rs:

#![allow(unused)]
#![forbid(unsafe_code)]
#![deny(
fn main() {
    clippy::unwrap_used,
    clippy::expect_used,
    clippy::panic,
    clippy::dbg_macro,
    clippy::print_stdout,
    clippy::print_stderr,
    clippy::todo,
    clippy::unimplemented,
)]
#![warn(
    clippy::pedantic,
    clippy::nursery,
    missing_docs,
)]
}

Tests and benches relax via #![allow(clippy::unwrap_used, clippy::expect_used)] at crate root for test binaries.

Custom rules

Output centralization

• No println! / eprintln! / print! / eprint! outside src/cli/output.rs.
• Enforced by clippy::print_stdout + clippy::print_stderr = deny.
• All output goes through the formatter which honors --json / --plain / TTY detection.

Error handling discipline

• Library modules (src/manifest, src/pack, src/plugin, src/actions, src/packtypes, src/fetchers, src/concurrency): use thiserror typed errors. anyhow banned here.
• Binary modules (src/cli, src/main.rs, src/mcp): may use anyhow.
• No unwrap() / expect() in production paths. Startup-only paths may expect() with a human-meaningful message if the invariant is unrecoverable (e.g. inventory registry empty = developer bug).

No direct shell-spawning outside actions/exec

• tokio::process::Command and std::process::Command allowed ONLY in src/actions/exec.rs, src/packtypes/scripted.rs, and src/fetchers/git.rs (for CLI fallback).
• Any other file invoking Command fails lint.
• Enforced by CI grep rule:

if grep -rn 'process::Command' src/ --include='*.rs' \
    | grep -vE '^src/(actions/exec|packtypes/scripted|fetchers/git)\.rs'; then
  echo "shell invocation outside allowed modules"; exit 1
fi

Path rules (ported from legacy .scripts/test.py)

• No hardcoded absolute paths in source, config, or embedded strings.

  • Banned: C:\, D:\, E:\, /home/, /Users/, /mnt/, /opt/.

  • CI grep:

    if grep -rn -E '([A-Z]:\\|/home/|/Users/|/mnt/|/opt/)' src/ --include='*.rs'; then
      echo "hardcoded path detected"; exit 1
    fi
    

• No ~ in source strings. Home expansion lives in a PackCtx::env helper using dirs::home_dir().

• No string concatenation with path separators. Use std::path::PathBuf + push()/join(). Clippy's path_buf_push_overwrite helps.

Manifest rules (runtime + lint)

• pack.yaml children[].path MUST be bare name. Enforced at parse by pack::schema::validate() and at doctor-time by grex doctor.
• grex.jsonl event path field likewise bare. No drive letters anywhere in manifest.

Plugin trait discipline

• Every module under src/actions/ MUST contain exactly one impl ActionPlugin.
• Every module under src/packtypes/ MUST contain exactly one impl PackTypePlugin.
• Every module under src/fetchers/ MUST contain exactly one impl Fetcher.
• Enforced by code review + presence of inventory::submit! block.

Shim rules — N/A

Legacy .scripts/ had Python-specific shim rules (no shutil.rmtree, no subprocess.run(shell=True), etc.). Rust has no direct analogue:

• std::fs::remove_dir_all is cross-platform — no native-script indirection needed.
• Shell invocation is already gated by the "no shell-spawning outside allowed modules" rule above.
• Symlinks use std::os::{unix,windows}::fs directly.

CI job

.github/workflows/lint.yml (or a job in ci.yml):

lint:
  runs-on: ubuntu-latest
  steps:
    - uses: actions/checkout@v4
    - uses: dtolnay/rust-toolchain@stable
      with: { components: rustfmt, clippy }
    - run: cargo fmt --all -- --check
    - run: cargo clippy --all-targets --all-features -- -D warnings
    - uses: crate-ci/typos@master
    - uses: EmbarkStudios/cargo-deny-action@v1
    - name: hardcoded paths
      run: |
        ! grep -rn -E '([A-Z]:\\|/home/|/Users/|/mnt/|/opt/)' src/ --include='*.rs'
    - name: shell invocation scope
      run: |
        ! grep -rn 'process::Command' src/ --include='*.rs' \
          | grep -vE '^src/(actions/exec|packtypes/scripted|fetchers/git)\.rs'

Pre-commit hook

.grex/hooks/pre-commit:

#!/usr/bin/env bash
set -e
cargo fmt --all -- --check
cargo clippy --all-targets --all-features -- -D warnings

Activated by grex init via git config core.hooksPath .grex/hooks.