atomic_waker.rs - mozsearch

Enable keyboard shortcuts

use crate::sync::AtomicWaker;

use tokio_test::task;

use std::task::Waker;

trait AssertSend: Send {}

trait AssertSync: Sync {}

impl AssertSend for AtomicWaker {}

impl AssertSync for AtomicWaker {}

impl AssertSend for Waker {}

impl AssertSync for Waker {}

#[cfg(tokio_wasm_not_wasi)]

use wasm_bindgen_test::wasm_bindgen_test as test;

#[test]

fn basic_usage() {

    let mut waker = task::spawn(AtomicWaker::new());

    waker.enter(|cx, waker| waker.register_by_ref(cx.waker()));

    waker.wake();

    assert!(waker.is_woken());

#[test]

fn wake_without_register() {

    let mut waker = task::spawn(AtomicWaker::new());

    waker.wake();

    // Registering should not result in a notification

    waker.enter(|cx, waker| waker.register_by_ref(cx.waker()));

    assert!(!waker.is_woken());

#[test]

#[cfg(not(tokio_wasm))] // wasm currently doesn't support unwinding

fn atomic_waker_panic_safe() {

    use std::panic;

    use std::ptr;

    use std::task::{RawWaker, RawWakerVTable, Waker};

    static PANICKING_VTABLE: RawWakerVTable = RawWakerVTable::new(

        |_| panic!("clone"),

        |_| unimplemented!("wake"),

        |_| unimplemented!("wake_by_ref"),

        |_| (),

);

    static NONPANICKING_VTABLE: RawWakerVTable = RawWakerVTable::new(

        |_| RawWaker::new(ptr::null(), &NONPANICKING_VTABLE),

        |_| unimplemented!("wake"),

        |_| unimplemented!("wake_by_ref"),

        |_| (),

);

    let panicking = unsafe { Waker::from_raw(RawWaker::new(ptr::null(), &PANICKING_VTABLE)) };

    let nonpanicking = unsafe { Waker::from_raw(RawWaker::new(ptr::null(), &NONPANICKING_VTABLE)) };

    let atomic_waker = AtomicWaker::new();

    let panicking = panic::AssertUnwindSafe(&panicking);

    let result = panic::catch_unwind(|| {

        let panic::AssertUnwindSafe(panicking) = panicking;

        atomic_waker.register_by_ref(panicking);

});

    assert!(result.is_err());

    assert!(atomic_waker.take_waker().is_none());

    atomic_waker.register_by_ref(&nonpanicking);

    assert!(atomic_waker.take_waker().is_some());