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|
#![warn(rust_2018_idioms)]
#![cfg(feature = "full")]
use std::sync::{
atomic::{AtomicU32, Ordering},
Arc,
};
use tokio::sync::SetOnce;
#[derive(Clone)]
struct DropCounter {
drops: Arc<AtomicU32>,
}
impl DropCounter {
fn new() -> Self {
DropCounter {
drops: Arc::new(AtomicU32::new(0)),
}
}
fn assert_num_drops(&self, value: u32) {
assert_eq!(value, self.drops.load(Ordering::Relaxed));
}
}
impl Drop for DropCounter {
fn drop(&mut self) {
self.drops.fetch_add(1, Ordering::Relaxed);
}
}
#[test]
fn drop_cell() {
let fooer = DropCounter::new();
let fooer_cl = fooer.clone();
{
let once_cell = SetOnce::new();
let prev = once_cell.set(fooer_cl);
assert!(prev.is_ok())
}
fooer.assert_num_drops(1);
}
#[test]
fn drop_cell_new_with() {
let fooer = DropCounter::new();
{
let once_cell = SetOnce::new_with(Some(fooer.clone()));
assert!(once_cell.initialized());
}
fooer.assert_num_drops(1);
}
#[test]
fn drop_into_inner() {
let fooer = DropCounter::new();
let once_cell = SetOnce::new();
assert!(once_cell.set(fooer.clone()).is_ok());
let val = once_cell.into_inner();
fooer.assert_num_drops(0);
drop(val);
fooer.assert_num_drops(1);
}
#[test]
fn drop_into_inner_new_with() {
let fooer = DropCounter::new();
let once_cell = SetOnce::new_with(Some(fooer.clone()));
let val = once_cell.into_inner();
fooer.assert_num_drops(0);
drop(val);
fooer.assert_num_drops(1);
}
#[test]
fn from() {
let cell = SetOnce::from(2);
assert_eq!(*cell.get().unwrap(), 2);
}
#[test]
fn set_and_get() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
ONCE.set(5).unwrap();
let value = ONCE.get().unwrap();
assert_eq!(*value, 5);
}
#[tokio::test]
async fn set_and_wait() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
tokio::spawn(async { ONCE.set(5) });
let value = ONCE.wait().await;
assert_eq!(*value, 5);
}
#[test]
#[cfg_attr(target_family = "wasm", ignore)]
fn set_and_wait_multiple_threads() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
let res1 = std::thread::spawn(|| ONCE.set(4));
let res2 = std::thread::spawn(|| ONCE.set(3));
let result_first = res1.join().unwrap().is_err();
let result_two = res2.join().unwrap().is_err();
assert!(result_first != result_two);
}
#[tokio::test]
#[cfg_attr(target_family = "wasm", ignore)]
async fn set_and_wait_threads() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
let thread = std::thread::spawn(|| {
ONCE.set(4).unwrap();
});
let value = ONCE.wait().await;
thread.join().unwrap();
assert_eq!(*value, 4);
}
#[test]
fn get_uninit() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
let uninit = ONCE.get();
assert!(uninit.is_none());
}
#[test]
fn set_twice() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
let first = ONCE.set(5);
assert_eq!(first, Ok(()));
let second = ONCE.set(6);
assert!(second.is_err());
}
#[test]
fn is_none_initializing() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
assert_eq!(ONCE.get(), None);
ONCE.set(20).unwrap();
assert!(ONCE.set(10).is_err());
}
#[tokio::test]
async fn is_some_initializing() {
static ONCE: SetOnce<u32> = SetOnce::const_new();
tokio::spawn(async { ONCE.set(20) });
assert_eq!(*ONCE.wait().await, 20);
}
#[test]
fn into_inner_int_empty_setonce() {
let once = SetOnce::<u32>::new();
let val = once.into_inner();
assert!(val.is_none());
}
|
