rust/library/alloc/tests/btree_set_hash.rs
Nicholas Nethercote 84ac80f192 Reformat use declarations.
The previous commit updated `rustfmt.toml` appropriately. This commit is
the outcome of running `x fmt --all` with the new formatting options.
2024-07-29 08:26:52 +10:00

31 lines
669 B
Rust

use std::collections::BTreeSet;
use crate::hash;
#[test]
fn test_hash() {
let mut x = BTreeSet::new();
let mut y = BTreeSet::new();
x.insert(1);
x.insert(2);
x.insert(3);
y.insert(3);
y.insert(2);
y.insert(1);
assert_eq!(hash(&x), hash(&y));
}
#[test]
fn test_prefix_free() {
let x = BTreeSet::from([1, 2, 3]);
let y = BTreeSet::<i32>::new();
// If hashed by iteration alone, `(x, y)` and `(y, x)` would visit the same
// order of elements, resulting in the same hash. But now that we also hash
// the length, they get distinct sequences of hashed data.
assert_ne!(hash(&(&x, &y)), hash(&(&y, &x)));
}