Diving into Rust with cloc-rs: A Line Counter CLI Tool

As a developer always eager to expand my skillset, I recently decided to delve into Rust programming. To make this learning experience practical and engaging, I created cloc-rs, a Rust implementation of the popular cloc (Count Lines of Code) utility.

What is cloc-rs?

cloc-rs is a command-line tool that counts the number of lines of code in files and directories. It's designed to be simple, fast, and flexible, allowing users to:

• Count lines in individual files or entire directories
• Filter by file extension
• Recursively traverse directories

The Implementation

The core of cloc-rs is built around two main functions:

1. count_lines: This function reads a file and counts its lines.
2. count_lines_in_repo: This function walks through a directory, applying filters if specified, and aggregates the line counts.

pub fn count_lines(file_path: &Path) -> io::Result<usize> {
    let file = fs::File::open(file_path)?;
    let reader = io::BufReader::new(file);
    Ok(reader.lines().count())
}

pub fn count_lines_in_repo(path: &Path, extension: Option<&str>) -> io::Result<usize> {
    // ... implementation details ...
}

To ensure reliability, I also added a comprehensive test suite, covering various scenarios and edge cases.

What I Learned

This project was an excellent introduction to Rust's key concepts:

• Ownership and borrowing
• Error handling with Result
• Working with filesystem operations
• Using external crates (like walkdir for directory traversal)

Try It Out!

If you're interested in exploring cloc-rs, you can find the full source code and installation instructions in the GitHub repository. Feel free to contribute or use it in your own projects!

This journey into Rust has been both challenging and rewarding. cloc-rs may be a simple tool, but it's been an invaluable learning experience in a language that's rapidly gaining popularity in systems programming and beyond.