use itertools::Itertools;
#[test]
fn specialization_intersperse() {
let mut iter = (1..2).intersperse(0);
iter.clone().for_each(|x| assert_eq!(Some(x), iter.next()));
let mut iter = (1..3).intersperse(0);
iter.clone().for_each(|x| assert_eq!(Some(x), iter.next()));
let mut iter = (1..4).intersperse(0);
iter.clone().for_each(|x| assert_eq!(Some(x), iter.next()));
}