servo/tests/unit/util/cache.rs
Matt Brubeck d2717c4475 Eliminate unneeded clones in find_or_create
...and use it to eliminate duplicate hash lookups and string copies in shape_text.
2016-05-13 18:20:25 -07:00

53 lines
1.8 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use std::cell::Cell;
use util::cache::{HashCache, LRUCache};
#[test]
fn test_hashcache() {
let mut cache: HashCache<usize, Cell<&str>> = HashCache::new();
cache.insert(1, Cell::new("one"));
assert!(cache.find(&1).is_some());
assert!(cache.find(&2).is_none());
cache.find_or_create(2, || { Cell::new("two") });
assert!(cache.find(&1).is_some());
assert!(cache.find(&2).is_some());
}
#[test]
fn test_lru_cache() {
let one = Cell::new("one");
let two = Cell::new("two");
let three = Cell::new("three");
let four = Cell::new("four");
// Test normal insertion.
let mut cache: LRUCache<usize, Cell<&str>> = LRUCache::new(2); // (_, _) (cache is empty)
cache.insert(1, one); // (1, _)
cache.insert(2, two); // (1, 2)
cache.insert(3, three); // (2, 3)
assert!(cache.find(&1).is_none()); // (2, 3) (no change)
assert!(cache.find(&3).is_some()); // (2, 3)
assert!(cache.find(&2).is_some()); // (3, 2)
// Test that LRU works (this insertion should replace 3, not 2).
cache.insert(4, four); // (2, 4)
assert!(cache.find(&1).is_none()); // (2, 4) (no change)
assert!(cache.find(&2).is_some()); // (4, 2)
assert!(cache.find(&3).is_none()); // (4, 2) (no change)
assert!(cache.find(&4).is_some()); // (2, 4) (no change)
// Test find_or_create.
cache.find_or_create(1, || { Cell::new("one") }); // (4, 1)
assert!(cache.find(&1).is_some()); // (4, 1) (no change)
assert!(cache.find(&2).is_none()); // (4, 1) (no change)
assert!(cache.find(&3).is_none()); // (4, 1) (no change)
assert!(cache.find(&4).is_some()); // (1, 4)
}