Insertion sort in Rust

insertion_sort.rs

fn insertion_sort(data: &mut Vec<u8>) {

    if data.len() < 2 { return; /* already sorted */ }

    for j in 1..data.len() {
        let key = data[j];
        let mut i = (j as i8) - 1;

        while i >= 0 && data[i as usize] > key {
            data[(i + 1) as usize] = data[i as usize];
            i -= 1;
        }

        data[(i + 1) as usize] = key;
    }
}

fn main() {
    let mut data = vec![5, 2, 4, 6, 1, 3];
    insertion_sort_reverse(&mut data);
    println!("{:?}", data);
}