facet-cargo-toml

Typed Cargo.toml and Cargo.lock parser using facet.

Features

• Complete Cargo.toml parsing: All manifest fields supported with proper types
• Cargo.lock parsing: Full lockfile support with dependency resolution
• Type-safe: Uses facet's derive macros for automatic parsing and validation
• Well-tested: Validated against hundreds of real-world Cargo.toml files

Usage

Add this to your Cargo.toml:

[dependencies]
facet-cargo-toml = "0.1"

Parse a Cargo.toml

use facet_cargo_toml::CargoManifest;

let manifest = CargoManifest::from_path("Cargo.toml")?;

if let Some(package) = &manifest.package {
    println!("Package name: {:?}", package.name);
    println!("Version: {:?}", package.version);
}

for (name, dep) in manifest.dependencies.unwrap_or_default() {
    println!("Dependency: {name} = {dep:?}");
}

Parse a Cargo.lock

use facet_cargo_toml::Lockfile;

let lockfile = Lockfile::from_path("Cargo.lock")?;

for package in &lockfile.package {
    println!("Locked package: {} {}", package.name, package.version);
}

API Overview

CargoManifest

Complete typed representation of Cargo.toml including:

• Package metadata
• Dependencies (regular, dev, build, target-specific)
• Workspace configuration
• Build targets (lib, bin, test, bench, example)
• Features
• Profiles
• Lints
• Patches

Lockfile

Typed representation of Cargo.lock including:

• Package list with versions and checksums
• Dependency resolution
• Source information (registry, git, path)

Why facet?

This crate uses the facet serialization framework which provides:

• Derive macros: Automatic parsing from TOML with #[derive(Facet)]
• Better error messages: Uses miette for beautiful parse error reporting
• Span information: Track the source location of every parsed value
• Type safety: Strong typing throughout with enums for variants

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.