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use futures::channel::mpsc;
use futures::channel::oneshot;
use futures::executor::{block_on, block_on_stream};
use futures::future::{err, ok};
use futures::stream::{empty, iter_ok, poll_fn, Peekable};
// mod support;
// use support::*;
pub struct Iter<I> {
iter: I,
}
pub fn iter<J, T, E>(i: J) -> Iter<J::IntoIter>
where
J: IntoIterator<Item = Result<T, E>>,
{
Iter { iter: i.into_iter() }
}
impl<I, T, E> Stream for Iter<I>
where
I: Iterator<Item = Result<T, E>>,
{
type Item = T;
type Error = E;
fn poll_next(&mut self, _: &mut Context<'_>) -> Poll<Option<T>, E> {
match self.iter.next() {
Some(Ok(e)) => Ok(Poll::Ready(Some(e))),
Some(Err(e)) => Err(e),
None => Ok(Poll::Ready(None)),
}
}
}
fn list() -> Box<Stream<Item = i32, Error = u32> + Send> {
let (tx, rx) = mpsc::channel(1);
tx.send(Ok(1)).and_then(|tx| tx.send(Ok(2))).and_then(|tx| tx.send(Ok(3))).forget();
Box::new(rx.then(|r| r.unwrap()))
}
fn err_list() -> Box<Stream<Item = i32, Error = u32> + Send> {
let (tx, rx) = mpsc::channel(1);
tx.send(Ok(1)).and_then(|tx| tx.send(Ok(2))).and_then(|tx| tx.send(Err(3))).forget();
Box::new(rx.then(|r| r.unwrap()))
}
#[test]
fn map() {
assert_done(|| list().map(|a| a + 1).collect(), Ok(vec![2, 3, 4]));
}
#[test]
fn map_err() {
assert_done(|| err_list().map_err(|a| a + 1).collect::<Vec<_>>(), Err(4));
}
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
struct FromErrTest(u32);
impl From<u32> for FromErrTest {
fn from(i: u32) -> Self {
Self(i)
}
}
#[test]
fn from_err() {
assert_done(|| err_list().err_into().collect::<Vec<_>>(), Err(FromErrTest(3)));
}
#[test]
fn fold() {
assert_done(|| list().fold(0, |a, b| ok::<i32, u32>(a + b)), Ok(6));
assert_done(|| err_list().fold(0, |a, b| ok::<i32, u32>(a + b)), Err(3));
}
#[test]
fn filter() {
assert_done(|| list().filter(|a| ok(*a % 2 == 0)).collect(), Ok(vec![2]));
}
#[test]
fn filter_map() {
assert_done(
|| list().filter_map(|x| ok(if x % 2 == 0 { Some(x + 10) } else { None })).collect(),
Ok(vec![12]),
);
}
#[test]
fn and_then() {
assert_done(|| list().and_then(|a| Ok(a + 1)).collect(), Ok(vec![2, 3, 4]));
assert_done(|| list().and_then(|a| err::<i32, u32>(a as u32)).collect::<Vec<_>>(), Err(1));
}
#[test]
fn then() {
assert_done(|| list().then(|a| a.map(|e| e + 1)).collect(), Ok(vec![2, 3, 4]));
}
#[test]
fn or_else() {
assert_done(|| err_list().or_else(|a| ok::<i32, u32>(a as i32)).collect(), Ok(vec![1, 2, 3]));
}
#[test]
fn flatten() {
assert_done(|| list().map(|_| list()).flatten().collect(), Ok(vec![1, 2, 3, 1, 2, 3, 1, 2, 3]));
}
#[test]
fn skip() {
assert_done(|| list().skip(2).collect(), Ok(vec![3]));
}
#[test]
fn skip_passes_errors_through() {
let mut s = block_on_stream(iter(vec![Err(1), Err(2), Ok(3), Ok(4), Ok(5)]).skip(1));
assert_eq!(s.next(), Some(Err(1)));
assert_eq!(s.next(), Some(Err(2)));
assert_eq!(s.next(), Some(Ok(4)));
assert_eq!(s.next(), Some(Ok(5)));
assert_eq!(s.next(), None);
}
#[test]
fn skip_while() {
assert_done(|| list().skip_while(|e| Ok(*e % 2 == 1)).collect(), Ok(vec![2, 3]));
}
#[test]
fn take() {
assert_done(|| list().take(2).collect(), Ok(vec![1, 2]));
}
#[test]
fn take_while() {
assert_done(|| list().take_while(|e| Ok(*e < 3)).collect(), Ok(vec![1, 2]));
}
#[test]
fn take_passes_errors_through() {
let mut s = block_on_stream(iter(vec![Err(1), Err(2), Ok(3), Ok(4), Err(4)]).take(1));
assert_eq!(s.next(), Some(Err(1)));
assert_eq!(s.next(), Some(Err(2)));
assert_eq!(s.next(), Some(Ok(3)));
assert_eq!(s.next(), None);
let mut s = block_on_stream(iter(vec![Ok(1), Err(2)]).take(1));
assert_eq!(s.next(), Some(Ok(1)));
assert_eq!(s.next(), None);
}
#[test]
fn peekable() {
assert_done(|| list().peekable().collect(), Ok(vec![1, 2, 3]));
}
#[test]
fn fuse() {
let mut stream = block_on_stream(list().fuse());
assert_eq!(stream.next(), Some(Ok(1)));
assert_eq!(stream.next(), Some(Ok(2)));
assert_eq!(stream.next(), Some(Ok(3)));
assert_eq!(stream.next(), None);
assert_eq!(stream.next(), None);
assert_eq!(stream.next(), None);
}
#[test]
fn buffered() {
let (tx, rx) = mpsc::channel(1);
let (a, b) = oneshot::channel::<u32>();
let (c, d) = oneshot::channel::<u32>();
tx.send(Box::new(b.recover(|_| panic!())) as Box<Future<Item = _, Error = _> + Send>)
.and_then(|tx| tx.send(Box::new(d.map_err(|_| panic!()))))
.forget();
let mut rx = rx.buffered(2);
sassert_empty(&mut rx);
c.send(3).unwrap();
sassert_empty(&mut rx);
a.send(5).unwrap();
let mut rx = block_on_stream(rx);
assert_eq!(rx.next(), Some(Ok(5)));
assert_eq!(rx.next(), Some(Ok(3)));
assert_eq!(rx.next(), None);
let (tx, rx) = mpsc::channel(1);
let (a, b) = oneshot::channel::<u32>();
let (c, d) = oneshot::channel::<u32>();
tx.send(Box::new(b.recover(|_| panic!())) as Box<Future<Item = _, Error = _> + Send>)
.and_then(|tx| tx.send(Box::new(d.map_err(|_| panic!()))))
.forget();
let mut rx = rx.buffered(1);
sassert_empty(&mut rx);
c.send(3).unwrap();
sassert_empty(&mut rx);
a.send(5).unwrap();
let mut rx = block_on_stream(rx);
assert_eq!(rx.next(), Some(Ok(5)));
assert_eq!(rx.next(), Some(Ok(3)));
assert_eq!(rx.next(), None);
}
#[test]
fn unordered() {
let (tx, rx) = mpsc::channel(1);
let (a, b) = oneshot::channel::<u32>();
let (c, d) = oneshot::channel::<u32>();
tx.send(Box::new(b.recover(|_| panic!())) as Box<Future<Item = _, Error = _> + Send>)
.and_then(|tx| tx.send(Box::new(d.recover(|_| panic!()))))
.forget();
let mut rx = rx.buffer_unordered(2);
sassert_empty(&mut rx);
let mut rx = block_on_stream(rx);
c.send(3).unwrap();
assert_eq!(rx.next(), Some(Ok(3)));
a.send(5).unwrap();
assert_eq!(rx.next(), Some(Ok(5)));
assert_eq!(rx.next(), None);
let (tx, rx) = mpsc::channel(1);
let (a, b) = oneshot::channel::<u32>();
let (c, d) = oneshot::channel::<u32>();
tx.send(Box::new(b.recover(|_| panic!())) as Box<Future<Item = _, Error = _> + Send>)
.and_then(|tx| tx.send(Box::new(d.recover(|_| panic!()))))
.forget();
// We don't even get to see `c` until `a` completes.
let mut rx = rx.buffer_unordered(1);
sassert_empty(&mut rx);
c.send(3).unwrap();
sassert_empty(&mut rx);
a.send(5).unwrap();
let mut rx = block_on_stream(rx);
assert_eq!(rx.next(), Some(Ok(5)));
assert_eq!(rx.next(), Some(Ok(3)));
assert_eq!(rx.next(), None);
}
#[test]
fn zip() {
assert_done(|| list().zip(list()).collect(), Ok(vec![(1, 1), (2, 2), (3, 3)]));
assert_done(|| list().zip(list().take(2)).collect(), Ok(vec![(1, 1), (2, 2)]));
assert_done(|| list().take(2).zip(list()).collect(), Ok(vec![(1, 1), (2, 2)]));
assert_done(|| err_list().zip(list()).collect::<Vec<_>>(), Err(3));
assert_done(|| list().zip(list().map(|x| x + 1)).collect(), Ok(vec![(1, 2), (2, 3), (3, 4)]));
}
#[test]
fn peek() {
struct Peek {
inner: Peekable<Box<Stream<Item = i32, Error = u32> + Send>>,
}
impl Future for Peek {
type Item = ();
type Error = u32;
fn poll(&mut self, cx: &mut Context<'_>) -> Poll<(), u32> {
{
let res = ready!(self.inner.peek(cx))?;
assert_eq!(res, Some(&1));
}
assert_eq!(self.inner.peek(cx).unwrap(), Some(&1).into());
assert_eq!(self.inner.poll_next(cx).unwrap(), Some(1).into());
Ok(Poll::Ready(()))
}
}
block_on(Peek { inner: list().peekable() }).unwrap()
}
#[test]
fn wait() {
assert_eq!(block_on_stream(list()).collect::<Result<Vec<_>, _>>(), Ok(vec![1, 2, 3]));
}
#[test]
fn chunks() {
assert_done(|| list().chunks(3).collect(), Ok(vec![vec![1, 2, 3]]));
assert_done(|| list().chunks(1).collect(), Ok(vec![vec![1], vec![2], vec![3]]));
assert_done(|| list().chunks(2).collect(), Ok(vec![vec![1, 2], vec![3]]));
let mut list = block_on_stream(err_list().chunks(3));
let i = list.next().unwrap().unwrap();
assert_eq!(i, vec![1, 2]);
let i = list.next().unwrap().unwrap_err();
assert_eq!(i, 3);
}
#[test]
#[should_panic]
fn chunks_panic_on_cap_zero() {
let _ = list().chunks(0);
}
#[test]
fn forward() {
let v = Vec::new();
let v = block_on(iter_ok::<_, Never>(vec![0, 1]).forward(v)).unwrap().1;
assert_eq!(v, vec![0, 1]);
let v = block_on(iter_ok::<_, Never>(vec![2, 3]).forward(v)).unwrap().1;
assert_eq!(v, vec![0, 1, 2, 3]);
assert_done(
move || iter_ok::<_, Never>(vec![4, 5]).forward(v).map(|(_, s)| s),
Ok(vec![0, 1, 2, 3, 4, 5]),
);
}
#[test]
fn concat() {
let a = iter_ok::<_, ()>(vec![vec![1, 2, 3], vec![4, 5, 6], vec![7, 8, 9]]);
assert_done(move || a.concat(), Ok(vec![1, 2, 3, 4, 5, 6, 7, 8, 9]));
let b = iter(vec![Ok::<_, ()>(vec![1, 2, 3]), Err(()), Ok(vec![7, 8, 9])]);
assert_done(move || b.concat(), Err(()));
}
#[test]
fn concat2() {
let a = iter_ok::<_, ()>(vec![vec![1, 2, 3], vec![4, 5, 6], vec![7, 8, 9]]);
assert_done(move || a.concat(), Ok(vec![1, 2, 3, 4, 5, 6, 7, 8, 9]));
let b = iter(vec![Ok::<_, ()>(vec![1, 2, 3]), Err(()), Ok(vec![7, 8, 9])]);
assert_done(move || b.concat(), Err(()));
let c = empty::<Vec<()>, ()>();
assert_done(move || c.concat(), Ok(vec![]))
}
#[test]
fn stream_poll_fn() {
let mut counter = 5usize;
let read_stream = poll_fn(move |_| -> Poll<Option<usize>, std::io::Error> {
if counter == 0 {
return Ok(Poll::Ready(None));
}
counter -= 1;
Ok(Poll::Ready(Some(counter)))
});
assert_eq!(block_on_stream(read_stream).count(), 5);
}
#[test]
fn inspect() {
let mut seen = vec![];
assert_done(|| list().inspect(|&a| seen.push(a)).collect(), Ok(vec![1, 2, 3]));
assert_eq!(seen, [1, 2, 3]);
}
#[test]
fn inspect_err() {
let mut seen = vec![];
assert_done(|| err_list().inspect_err(|&a| seen.push(a)).collect::<Vec<_>>(), Err(3));
assert_eq!(seen, [3]);
}