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#![cfg(feature = "use_std")]
#![allow(bare_trait_objects, unknown_lints)]
extern crate futures;
mod support;
use futures::prelude::*;
use futures::unsync::oneshot;
use futures::unsync::mpsc::{self, SendError};
use futures::future::lazy;
use futures::stream::{iter_ok, unfold};
use support::local_executor::Core;
#[test]
fn mpsc_send_recv() {
let (tx, rx) = mpsc::channel::<i32>(1);
let mut rx = rx.wait();
tx.send(42).wait().unwrap();
assert_eq!(rx.next(), Some(Ok(42)));
assert_eq!(rx.next(), None);
}
#[test]
fn mpsc_rx_notready() {
let (_tx, mut rx) = mpsc::channel::<i32>(1);
lazy(|| {
assert_eq!(rx.poll().unwrap(), Async::NotReady);
Ok(()) as Result<(), ()>
}).wait().unwrap();
}
#[test]
fn mpsc_rx_end() {
let (_, mut rx) = mpsc::channel::<i32>(1);
lazy(|| {
assert_eq!(rx.poll().unwrap(), Async::Ready(None));
Ok(()) as Result<(), ()>
}).wait().unwrap();
}
#[test]
fn mpsc_tx_clone_weak_rc() {
let (tx, mut rx) = mpsc::channel::<i32>(1); // rc = 1
let tx_clone = tx.clone(); // rc = 2
lazy(|| {
assert_eq!(rx.poll().unwrap(), Async::NotReady);
Ok(()) as Result<(), ()>
}).wait().unwrap();
drop(tx); // rc = 1
lazy(|| {
assert_eq!(rx.poll().unwrap(), Async::NotReady);
Ok(()) as Result<(), ()>
}).wait().unwrap();
drop(tx_clone); // rc = 0
lazy(|| {
assert_eq!(rx.poll().unwrap(), Async::Ready(None));
Ok(()) as Result<(), ()>
}).wait().unwrap();
}
#[test]
fn mpsc_tx_notready() {
let (tx, _rx) = mpsc::channel::<i32>(1);
let tx = tx.send(1).wait().unwrap();
lazy(move || {
assert!(tx.send(2).poll().unwrap().is_not_ready());
Ok(()) as Result<(), ()>
}).wait().unwrap();
}
#[test]
fn mpsc_tx_err() {
let (tx, _) = mpsc::channel::<i32>(1);
lazy(move || {
assert!(tx.send(2).poll().is_err());
Ok(()) as Result<(), ()>
}).wait().unwrap();
}
#[test]
fn mpsc_backpressure() {
let (tx, rx) = mpsc::channel::<i32>(1);
lazy(move || {
iter_ok(vec![1, 2, 3])
.forward(tx)
.map_err(|e: SendError<i32>| panic!("{}", e))
.join(rx.take(3).collect().map(|xs| {
assert_eq!(xs, [1, 2, 3]);
}))
}).wait().unwrap();
}
#[test]
fn mpsc_unbounded() {
let (tx, rx) = mpsc::unbounded::<i32>();
lazy(move || {
iter_ok(vec![1, 2, 3])
.forward(tx)
.map_err(|e: SendError<i32>| panic!("{}", e))
.join(rx.take(3).collect().map(|xs| {
assert_eq!(xs, [1, 2, 3]);
}))
}).wait().unwrap();
}
#[test]
fn mpsc_recv_unpark() {
let core = Core::new();
let (tx, rx) = mpsc::channel::<i32>(1);
let tx2 = tx.clone();
core.spawn(rx.collect().map(|xs| assert_eq!(xs, [1, 2])));
core.spawn(lazy(move || tx.send(1).map(|_| ()).map_err(|e| panic!("{}", e))));
core.run(lazy(move || tx2.send(2))).unwrap();
}
#[test]
fn mpsc_send_unpark() {
let core = Core::new();
let (tx, rx) = mpsc::channel::<i32>(1);
let (donetx, donerx) = oneshot::channel();
core.spawn(iter_ok(vec![1, 2]).forward(tx)
.then(|x: Result<_, SendError<i32>>| {
assert!(x.is_err());
donetx.send(()).unwrap();
Ok(())
}));
core.spawn(lazy(move || { let _ = rx; Ok(()) }));
core.run(donerx).unwrap();
}
#[test]
fn spawn_sends_items() {
let core = Core::new();
let stream = unfold(0, |i| Some(Ok::<_,u8>((i, i + 1))));
let rx = mpsc::spawn(stream, &core, 1);
assert_eq!(core.run(rx.take(4).collect()).unwrap(),
[0, 1, 2, 3]);
}
#[test]
fn spawn_kill_dead_stream() {
use std::thread;
use std::time::Duration;
use futures::future::Either;
// a stream which never returns anything (maybe a remote end isn't
// responding), but dropping it leads to observable side effects
// (like closing connections, releasing limited resources, ...)
#[derive(Debug)]
struct Dead {
// when dropped you should get Err(oneshot::Canceled) on the
// receiving end
done: oneshot::Sender<()>,
}
impl Stream for Dead {
type Item = ();
type Error = ();
fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> {
Ok(Async::NotReady)
}
}
// need to implement a timeout for the test, as it would hang
// forever right now
let (timeout_tx, timeout_rx) = futures::sync::oneshot::channel();
thread::spawn(move || {
thread::sleep(Duration::from_millis(1000));
let _ = timeout_tx.send(());
});
let core = Core::new();
let (done_tx, done_rx) = oneshot::channel();
let stream = Dead{done: done_tx};
let rx = mpsc::spawn(stream, &core, 1);
let res = core.run(
Ok::<_, ()>(())
.into_future()
.then(move |_| {
// now drop the spawned stream: maybe some timeout exceeded,
// or some connection on this end was closed by the remote
// end.
drop(rx);
// and wait for the spawned stream to release its resources
done_rx
})
.select2(timeout_rx)
);
match res {
Err(Either::A((oneshot::Canceled, _))) => (),
_ => {
panic!("dead stream wasn't canceled");
},
}
}
/// Test case for PR #768 (issue #766).
/// The issue was:
/// Given that an empty channel is polled by the Receiver, and the only Sender
/// gets dropped without sending anything, then the Receiver would get stuck.
#[test]
fn dropped_sender_of_unused_channel_notifies_receiver() {
let core = Core::new();
type FUTURE = Box<futures::Future<Item=u8, Error=()>>;
// Constructs the channel which we want to test, and two futures which
// act on that channel.
let pair = |reverse| -> Vec<FUTURE> {
// This is the channel which we want to test.
let (tx, rx) = mpsc::channel::<u8>(1);
let mut futures: Vec<FUTURE> = vec![
Box::new(futures::stream::iter_ok(vec![])
.forward(tx)
.map_err(|_: mpsc::SendError<u8>| ())
.map(|_| 42)
),
Box::new(rx.fold((), |_, _| Ok(()))
.map(|_| 24)
),
];
if reverse {
futures.reverse();
}
futures
};
let make_test_future = |reverse| -> Box<Future<Item=Vec<u8>, Error=()>> {
let f = futures::future::join_all(pair(reverse));
// Use a timeout. This is not meant to test the `sync::oneshot` but
// merely uses it to implement this timeout.
let (timeout_tx, timeout_rx) = futures::sync::oneshot::channel::<Vec<u8>>();
std::thread::spawn(move || {
std::thread::sleep(std::time::Duration::from_millis(1000));
let x = timeout_tx.send(vec![0]);
assert!(x.is_err(), "Test timed out.");
});
Box::new(f.select(timeout_rx.map_err(|_|()))
.map_err(|x| x.0)
.map(|x| x.0)
)
};
// The order of the tested futures is important to test fix of PR #768.
// We want future_2 to poll on the Receiver before the Sender is dropped.
let result = core.run(make_test_future(false));
assert!(result.is_ok());
assert_eq!(vec![42, 24], result.unwrap());
// Test also the other ordering:
let result = core.run(make_test_future(true));
assert!(result.is_ok());
assert_eq!(vec![24, 42], result.unwrap());
}
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