vendor/futures-0.3.27/tests/future_select_ok.rs

use futures::executor::block_on;
use futures::future::{err, ok, select_ok};

#[test]
fn ignore_err() {
    let v = vec![err(1), err(2), ok(3), ok(4)];

    let (i, v) = block_on(select_ok(v)).ok().unwrap();
    assert_eq!(i, 3);

    assert_eq!(v.len(), 1);

    let (i, v) = block_on(select_ok(v)).ok().unwrap();
    assert_eq!(i, 4);

    assert!(v.is_empty());
}

#[test]
fn last_err() {
    let v = vec![ok(1), err(2), err(3)];

    let (i, v) = block_on(select_ok(v)).ok().unwrap();
    assert_eq!(i, 1);

    assert_eq!(v.len(), 2);

    let i = block_on(select_ok(v)).err().unwrap();
    assert_eq!(i, 3);
}