rust/tests/pass/linked-list.rs
2022-06-20 16:09:45 -07:00

52 lines
1.5 KiB
Rust

#![feature(linked_list_cursors)]
use std::collections::LinkedList;
fn list_from<T: Clone>(v: &[T]) -> LinkedList<T> {
v.iter().cloned().collect()
}
// Gather all references from a mutable iterator and make sure Miri notices if
// using them is dangerous.
fn test_all_refs<'a, T: 'a>(dummy: &mut T, iter: impl Iterator<Item = &'a mut T>) {
// Gather all those references.
let mut refs: Vec<&mut T> = iter.collect();
// Use them all. Twice, to be sure we got all interleavings.
for r in refs.iter_mut() {
std::mem::swap(dummy, r);
}
for r in refs {
std::mem::swap(dummy, r);
}
}
fn main() {
let mut m = list_from(&[0, 2, 4, 6, 8]);
let len = m.len();
{
let mut it = m.cursor_front_mut();
it.insert_before(-2);
loop {
match it.current().copied() {
None => break,
Some(elt) => {
match it.peek_next() {
Some(x) => assert_eq!(*x, elt + 2),
None => assert_eq!(8, elt),
}
it.insert_after(elt + 1);
it.move_next(); // Move by 2 to skip the one we inserted.
it.move_next();
}
}
}
it.insert_before(99);
it.insert_after(-10);
}
assert_eq!(m.len(), 3 + len * 2);
let mut m2 = m.clone();
assert_eq!(m.into_iter().collect::<Vec<_>>(), [-10, -2, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 99]);
test_all_refs(&mut 13, m2.iter_mut());
}