Linguist

A Rust library for programming language detection, inspired by GitHub Linguist. Detects programming languages by file extension, filename, and content-based heuristics.

Features

• Zero configuration and setup required, just add the crate and call the detection functions
• Detect languages by exact filename match (e.g., Makefile, Dockerfile)
• Detect languages by file extension (e.g., .rs, .py, .js)
• Disambiguate between multiple languages using content heuristics
• Identify vendored/third-party files

Usage

Detect by Extension

use linguist::detect_language_by_extension;

let languages = detect_language_by_extension("script.py")?;
assert_eq!(languages[0].name, "Python");

Detect by Filename

use linguist::detect_language_by_filename;

let languages = detect_language_by_filename("Makefile")?;
assert_eq!(languages[0].name, "Makefile");

Disambiguate by Content

use linguist::disambiguate;

let content = "#include <iostream>\nint main() {}";
let result = disambiguate("test.h", content)?;
if let Some(languages) = result {
    assert_eq!(languages[0].name, "C++");
}

Check if Vendored

use linguist::is_vendored;

assert!(is_vendored("node_modules/react/index.js")?);
assert!(!is_vendored("src/main.rs")?);

Acknowledgments

Special thanks to @vcfxb for graciously donating the crates.io name "linguist" to this project!

This project is inspired by and uses language definitions from GitHub Linguist, maintained by GitHub and its contributors. The language definitions (definitions/languages.yml, definitions/heuristics.yml, definitions/vendor.yml) are derived from this project.

Maintaining

See MAINTAINING.md for how to sync definitions and test samples with upstream github-linguist.