Order-resistant JSON diffing cargo script

jsoncmp.rs

#!/usr/bin/env run-cargo-script
//! ```cargo
//! [package]
//! edition = "2018"
//!
//! [dependencies]
//! serde = "1.0"
//! serde_json = "1.0"
//! ```

use serde_json::Value;
use std::{
    fs::File,
    io::{BufRead, BufReader},
};

fn main() {
    let old_file = std::env::args().nth(1).unwrap();
    let new_file = std::env::args().nth(2).unwrap();

    for (old_line, new_line) in BufReader::new(File::open(&old_file).unwrap())
        .lines()
        .zip(BufReader::new(File::open(&new_file).unwrap()).lines())
    {
        let mut old_json = serde_json::from_str::<Value>(&old_line.unwrap()).unwrap();
        let mut new_json = serde_json::from_str::<Value>(&new_line.unwrap()).unwrap();
        sort_arrays(&mut old_json);
        sort_arrays(&mut new_json);

        if new_json != old_json {
            println!("Match fail between {} and {}", new_file, old_file);
            std::process::exit(-1);
        }
    }
}

fn sort_arrays(this: &mut Value) {
    match this {
        Value::Array(arr) => {
            arr.sort_by(|a, b| a.to_string().cmp(&b.to_string()));
            for value in arr {
                sort_arrays(value);
            }
        }
        Value::Object(map) => {
            for value in map.values_mut() {
                sort_arrays(value);
            }
        }
        _ => {}
    }
}