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#![allow(bare_trait_objects, unknown_lints)]
extern crate futures;
mod support;
use std::cell::RefCell;
use std::rc::Rc;
use std::thread;
use futures::sync::oneshot;
use futures::prelude::*;
use futures::future;
fn send_shared_oneshot_and_wait_on_multiple_threads(threads_number: u32) {
let (tx, rx) = oneshot::channel::<u32>();
let f = rx.shared();
let threads = (0..threads_number).map(|_| {
let cloned_future = f.clone();
thread::spawn(move || {
assert_eq!(*cloned_future.wait().unwrap(), 6);
})
}).collect::<Vec<_>>();
tx.send(6).unwrap();
assert_eq!(*f.wait().unwrap(), 6);
for f in threads {
f.join().unwrap();
}
}
#[test]
fn one_thread() {
send_shared_oneshot_and_wait_on_multiple_threads(1);
}
#[test]
fn two_threads() {
send_shared_oneshot_and_wait_on_multiple_threads(2);
}
#[test]
fn many_threads() {
send_shared_oneshot_and_wait_on_multiple_threads(1000);
}
#[test]
fn drop_on_one_task_ok() {
let (tx, rx) = oneshot::channel::<u32>();
let f1 = rx.shared();
let f2 = f1.clone();
let (tx2, rx2) = oneshot::channel::<u32>();
let t1 = thread::spawn(|| {
let f = f1.map_err(|_| ()).map(|x| *x).select(rx2.map_err(|_| ()));
drop(f.wait());
});
let (tx3, rx3) = oneshot::channel::<u32>();
let t2 = thread::spawn(|| {
let _ = f2.map(|x| tx3.send(*x).unwrap()).map_err(|_| ()).wait();
});
tx2.send(11).unwrap(); // cancel `f1`
t1.join().unwrap();
tx.send(42).unwrap(); // Should cause `f2` and then `rx3` to get resolved.
let result = rx3.wait().unwrap();
assert_eq!(result, 42);
t2.join().unwrap();
}
#[test]
fn drop_in_poll() {
let slot = Rc::new(RefCell::new(None));
let slot2 = slot.clone();
let future = future::poll_fn(move || {
drop(slot2.borrow_mut().take().unwrap());
Ok::<_, u32>(1.into())
}).shared();
let future2 = Box::new(future.clone()) as Box<Future<Item=_, Error=_>>;
*slot.borrow_mut() = Some(future2);
assert_eq!(*future.wait().unwrap(), 1);
}
#[test]
fn peek() {
let core = ::support::local_executor::Core::new();
let (tx0, rx0) = oneshot::channel::<u32>();
let f1 = rx0.shared();
let f2 = f1.clone();
// Repeated calls on the original or clone do not change the outcome.
for _ in 0..2 {
assert!(f1.peek().is_none());
assert!(f2.peek().is_none());
}
// Completing the underlying future has no effect, because the value has not been `poll`ed in.
tx0.send(42).unwrap();
for _ in 0..2 {
assert!(f1.peek().is_none());
assert!(f2.peek().is_none());
}
// Once the Shared has been polled, the value is peekable on the clone.
core.spawn(f1.map(|_|()).map_err(|_|()));
core.run(future::ok::<(),()>(())).unwrap();
for _ in 0..2 {
assert_eq!(42, *f2.peek().unwrap().unwrap());
}
}
#[test]
fn polled_then_ignored() {
let core = ::support::local_executor::Core::new();
let (tx0, rx0) = oneshot::channel::<u32>();
let f1 = rx0.shared();
let f2 = f1.clone();
let (tx1, rx1) = oneshot::channel::<u32>();
let (tx2, rx2) = oneshot::channel::<u32>();
let (tx3, rx3) = oneshot::channel::<u32>();
core.spawn(f1.map(|n| tx3.send(*n).unwrap()).map_err(|_|()));
core.run(future::ok::<(),()>(())).unwrap(); // Allow f1 to be polled.
core.spawn(f2.map_err(|_| ()).map(|x| *x).select(rx2.map_err(|_| ())).map_err(|_| ())
.and_then(|(_, f2)| rx3.map_err(|_| ()).map(move |n| {drop(f2); tx1.send(n).unwrap()})));
core.run(future::ok::<(),()>(())).unwrap(); // Allow f2 to be polled.
tx2.send(11).unwrap(); // Resolve rx2, causing f2 to no longer get polled.
core.run(future::ok::<(),()>(())).unwrap(); // Let the send() propagate.
tx0.send(42).unwrap(); // Should cause f1, then rx3, and then rx1 to resolve.
assert_eq!(core.run(rx1).unwrap(), 42);
}
#[test]
fn recursive_poll() {
use futures::sync::mpsc;
use futures::Stream;
let core = ::support::local_executor::Core::new();
let (tx0, rx0) = mpsc::unbounded::<Box<Future<Item=(),Error=()>>>();
let run_stream = rx0.for_each(|f| f);
let (tx1, rx1) = oneshot::channel::<()>();
let f1 = run_stream.shared();
let f2 = f1.clone();
let f3 = f1.clone();
tx0.unbounded_send(Box::new(
f1.map(|_|()).map_err(|_|())
.select(rx1.map_err(|_|()))
.map(|_| ()).map_err(|_|()))).unwrap();
core.spawn(f2.map(|_|()).map_err(|_|()));
// Call poll() on the spawned future. We want to be sure that this does not trigger a
// deadlock or panic due to a recursive lock() on a mutex.
core.run(future::ok::<(),()>(())).unwrap();
tx1.send(()).unwrap(); // Break the cycle.
drop(tx0);
core.run(f3).unwrap();
}
#[test]
fn recursive_poll_with_unpark() {
use futures::sync::mpsc;
use futures::{Stream, task};
let core = ::support::local_executor::Core::new();
let (tx0, rx0) = mpsc::unbounded::<Box<Future<Item=(),Error=()>>>();
let run_stream = rx0.for_each(|f| f);
let (tx1, rx1) = oneshot::channel::<()>();
let f1 = run_stream.shared();
let f2 = f1.clone();
let f3 = f1.clone();
tx0.unbounded_send(Box::new(future::lazy(move || {
task::current().notify();
f1.map(|_|()).map_err(|_|())
.select(rx1.map_err(|_|()))
.map(|_| ()).map_err(|_|())
}))).unwrap();
core.spawn(f2.map(|_|()).map_err(|_|()));
// Call poll() on the spawned future. We want to be sure that this does not trigger a
// deadlock or panic due to a recursive lock() on a mutex.
core.run(future::ok::<(),()>(())).unwrap();
tx1.send(()).unwrap(); // Break the cycle.
drop(tx0);
core.run(f3).unwrap();
}
#[test]
fn shared_future_that_wakes_itself_until_pending_is_returned() {
use futures::Async;
use std::cell::Cell;
let core = ::support::local_executor::Core::new();
let proceed = Cell::new(false);
let fut = futures::future::poll_fn(|| {
Ok::<_, ()>(if proceed.get() {
Async::Ready(())
} else {
futures::task::current().notify();
Async::NotReady
})
})
.shared()
.map(|_| ())
.map_err(|_| ());
// The join future can only complete if the second future gets a chance to run after the first
// has returned pending
let second = futures::future::lazy(|| {
proceed.set(true);
Ok::<_, ()>(())
});
core.run(fut.join(second)).unwrap();
}
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