convention-lint

A file-naming convention linter for Rust projects. Configure it once in Cargo.toml, run it as a Cargo subcommand.

Uses the ignore crate for parallel directory traversal (same as ripgrep), so it respects .gitignore and skips hidden files out of the box. Errors are printed in rustc/clippy style.

Installation

cargo install convention-lint

The binary is named cargo-convention-lint, so Cargo picks it up automatically as a subcommand:

cargo convention-lint

Configuration

Add a [package.metadata.convention-lint] section to your Cargo.toml. Each key is a file extension mapped to a convention name.

Single package:

[package.metadata.convention-lint]

rs = "CamelCase"



[package.metadata.convention-lint.dirs]

rs = ["src/models"]

Workspace — put the config in the root Cargo.toml under [workspace.metadata]:

[workspace.metadata.convention-lint]

rs    = "snake_case"

idl   = "snake_case"

proto = "snake_case"



[workspace.metadata.convention-lint.dirs]

idl = ["src/idl", "proto"]

# extensions without a dirs entry are scanned recursively

Then run:

cargo convention-lint

# or point at a specific manifest:

cargo convention-lint --manifest-path path/to/Cargo.toml

Exit code is 0 if everything passes, 1 if there are violations.

Supported conventions

PascalCase is accepted as an alias for CamelCase.

Output

error[convention]: `src/idl/MyService.idl` — stem `MyService` does not follow snake_case convention
error[convention]: `src/idl/badName.idl` — stem `badName` does not follow snake_case convention

convention-lint: found 2 naming violation(s)

Testing

tests/fixtures/ contains two small projects you can run against directly:

tests/fixtures/
├── pass/          ← all files conform → exit 0
│   ├── Cargo.toml
│   ├── idl/
│   │   ├── my_service.idl
│   │   └── order_processor.idl
│   └── src/
│       └── my_module.rs
└── fail/          ← intentional violations → exit 1
    ├── Cargo.toml
    ├── idl/
    │   ├── my_service.idl    ✓
    │   ├── MyService.idl     ✗  (should be snake_case)
    │   └── another_Bad.idl   ✗
    └── src/
        ├── OrderProcessor.rs ✓
        └── bad_module.rs     ✗  (should be CamelCase)

cargo run -- convention-lint --manifest-path tests/fixtures/pass/Cargo.toml

cargo run -- convention-lint --manifest-path tests/fixtures/fail/Cargo.toml

Full test suite:

cargo test

CI

GitHub Actions

- name: Install convention-lint
  uses: taiki-e/install-action@v2
  with:
    tool: convention-lint

- name: Check naming conventions
  run: cargo convention-lint

Pre-commit hook

#!/bin/sh

cargo convention-lint || exit 1

Library usage

The crate also works as a library if you want to embed it in a build script or another tool:

[dependencies]

convention-lint = "0.1"

use convention_lint::{config::load_config, lint::run};
use std::path::Path;

fn main() {
    let cfg = load_config(Path::new("Cargo.toml")).expect("failed to load config");
    let violations = run(&cfg, Path::new("."));

    for v in &violations {
        eprintln!("{v}");
    }

    if !violations.is_empty() {
        std::process::exit(1);
    }
}

Public API:

Full docs on docs.rs/convention-lint.

License

• MIT
• Apache 2.0,