Used for concatenating all code in a dir into a single output for homework submission

catall.rs

use std::{env, fs};
use std::fs::File;
use std::io::Read;
use std::path::PathBuf;
use std::process::exit;

fn output_help() {
    println!("Usage: catall [OPTIONS] <directory>\n");
    println!("Concatenates all files within a directory to output");
    println!("Options:");
    println!("\t -t (Prepend fine contents with file name)");
}

fn main() {
    let mut args : Vec<String> = env::args().collect();
    let mut prepend_file_name = false;
    if let Some(index) = args.iter().position(|x| *x == "-t") {
        args.remove(index);
        prepend_file_name = true;
    }

    if args.len() == 1 {
        output_help();
        exit(0);
    }

    let path = args.get(1).unwrap();
    let mut out = String::new();
    walk(PathBuf::from(path), prepend_file_name, &mut out);
    print!("{}", out);
}

fn walk(path : PathBuf, prepend_file_name : bool, output : &mut String) {
    let dirs = match fs::read_dir(path) {
        Ok(dir) => dir,
        Err(e) => {
            println!("{}", e);
            exit(1);
        }
    };

    for dir in dirs {
        if let Err(e) = dir {
            println!("{}", e);
            exit(1);
        }

        let new_path = dir.unwrap().path();
        if new_path.is_dir() {
            walk(new_path, prepend_file_name, output);
        }
        else {
            let file = File::open(&new_path);
            match file {
                Ok(mut file) => {
                    let path = new_path.as_os_str().to_str().unwrap().to_owned();

                    output.push_str(&format!("// {}\n", path));
                    let mut str = String::new();
                    file.read_to_string(&mut str).unwrap();
                    output.push_str(&format!("{}\n", str));
                }
                Err(e) => {
                    println!("{}", e)
                }
            }
        }
    }
}