pub(crate) struct DropGuard<F: Fn()>(pub(crate) F);
impl<F: Fn()> DropGuard<F> {
pub(crate) fn disarm(self) {
std::mem::forget(self)
}
}
impl<F> Drop for DropGuard<F>
where
F: Fn(),
{
fn drop(&mut self) {
(self.0)()
}
}
#[test]
fn test_dropguard_drop() {
use std::sync::atomic::{AtomicUsize, Ordering};
let count = AtomicUsize::new(0);
assert_eq!(count.load(Ordering::Relaxed), 0);
{
let _ = count.fetch_add(1, Ordering::Relaxed);
let _ = DropGuard(|| {
let _ = count.fetch_sub(1, Ordering::Relaxed);
});
}
assert_eq!(count.load(Ordering::Relaxed), 0);
}
#[test]
fn test_dropguard_disarm() {
use std::sync::atomic::{AtomicUsize, Ordering};
let count = AtomicUsize::new(0);
assert_eq!(count.load(Ordering::Relaxed), 0);
{
let _ = count.fetch_add(1, Ordering::Relaxed);
let guard = DropGuard(|| {
let _ = count.fetch_sub(1, Ordering::Relaxed);
});
guard.disarm();
}
assert_eq!(count.load(Ordering::Relaxed), 1);
}