barrage 0.2.3

An async broadcast channel
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310

use barrage::{Disconnected, SendError};
use std::future::Future;
use std::pin::Pin;
use std::task::{Context, Poll};
use tokio::time::Duration;
use std::sync::Arc;
use std::thread;
use tokio_test::assert_ok;
use std::sync::atomic::{AtomicBool, Ordering};

struct PollOnce<'a, F: Future + Unpin>(&'a mut F);

impl<'a, F: Future + Unpin> Future for PollOnce<'a, F> {
    type Output = Poll<F::Output>;

    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
        Poll::Ready(Pin::new(&mut self.0).poll(cx))
    }
}

#[tokio::test]
async fn one_message_unbounded() {
    let (tx, rx) = barrage::new(None);
    let rx2 = rx.clone();
    tx.send_async("Hello!").await.unwrap();
    assert_eq!(rx.recv_async().await, Ok("Hello!"));
    assert_eq!(rx2.recv_async().await, Ok("Hello!"));
}

#[test]
fn shared_recv() {
    let (tx, rx) = barrage::new(None);
    let mut fut1 = rx.recv_async();
    let mut fut2 = rx.recv_async();
    let pin1 = Pin::new(&mut fut1);
    let pin2 = Pin::new(&mut fut2);

    let woken1 = Arc::new(AtomicBool::new(false));
    let woken2 = Arc::new(AtomicBool::new(false));
    let woken1_clone = woken1.clone();
    let woken2_clone = woken2.clone();

    let waker = waker_fn::waker_fn(move || woken1_clone.store(true, Ordering::SeqCst));
    let waker2 = waker_fn::waker_fn(move || woken2_clone.store(true, Ordering::SeqCst));
    assert!(pin1.poll(&mut Context::from_waker(&waker)).is_pending());
    assert!(pin2.poll(&mut Context::from_waker(&waker2)).is_pending());

    tx.send("Hello!").unwrap();

    assert!(woken1.load(Ordering::SeqCst));
    assert!(woken2.load(Ordering::SeqCst));

    let pin1 = Pin::new(&mut fut1);
    let pin2 = Pin::new(&mut fut2);
    assert!(pin1.poll(&mut Context::from_waker(&waker)).is_ready());
    assert!(pin2.poll(&mut Context::from_waker(&waker2)).is_pending());
}

#[tokio::test]
async fn sync_receive_from_wait_async_send() {
    let (tx, rx) = barrage::new(None);

    let handle = tokio::task::spawn_blocking(move || {
        assert_eq!("Hello!", rx.recv().unwrap());
    });

    tokio::time::delay_for(Duration::from_millis(500)).await;
    tx.send_async("Hello!").await.unwrap();
    handle.await.unwrap();
}

#[tokio::test]
async fn sync_receive_from_wait_try_send() {
    let (tx, rx) = barrage::new(None);

    let handle = tokio::task::spawn_blocking(move || {
        assert_eq!("Hello!", rx.recv().unwrap());
    });

    tokio::time::delay_for(Duration::from_millis(500)).await;
    tx.try_send("Hello!").unwrap();
    handle.await.unwrap();
}

#[tokio::test]
async fn sync_receive() {
    let (tx, rx) = barrage::new(None);

    tx.send_async("Hello!").await.unwrap();
    assert_eq!("Hello!", rx.recv().unwrap());
}

#[tokio::test]
async fn new_recv_after_send() {
    let (tx, rx) = barrage::new(None);
    tx.send_async("Hello!").await.unwrap();
    let rx2 = rx.clone();
    tx.send_async("Hello 2!").await.unwrap();
    assert_eq!(rx.recv_async().await, Ok("Hello!"));
    assert_eq!(rx2.recv_async().await, Ok("Hello 2!"));
}

#[tokio::test]
async fn tx_drop_disconnect() {
    let (tx, rx) = barrage::new(None);
    tx.send_async("Hello!").await.unwrap();
    drop(tx);
    let rx2 = rx.clone();
    assert_eq!(rx2.recv_async().await, Err(Disconnected));
    assert_eq!(rx2.recv_async().await, Err(Disconnected));
    assert_eq!(rx.recv_async().await, Ok("Hello!"));
    assert_eq!(rx.recv_async().await, Err(Disconnected));
    assert_eq!(rx.recv_async().await, Err(Disconnected));
}

#[tokio::test]
async fn rx_drop_disconnect() {
    let (tx, rx) = barrage::new(None);
    let _tx2 = tx.clone();
    tx.send_async("Hello!").await.unwrap();
    drop(rx);
    assert_eq!(tx.send_async("Hello!").await, Err(SendError("Hello!")));
    assert_eq!(tx.send_async("Hello!").await, Err(SendError("Hello!")));
}

#[tokio::test]
async fn bounded_wait_resume() {
    let (tx, rx) = barrage::new(Some(1));
    tx.send_async("Hello!").await.unwrap();
    let mut fut = tx.send_async("Hello!");
    assert_eq!(PollOnce(&mut fut).await, Poll::Pending);
    assert_eq!(rx.recv_async().await, Ok("Hello!"));
    assert_eq!(PollOnce(&mut fut).await, Poll::Ready(Ok(())));
}

#[tokio::test]
async fn try_send_bounded_wait_resume() {
    let (tx, rx) = barrage::new(Some(1));
    tx.try_send("Hello!").unwrap();
    let mut fut = tx.send_async("Hello!");
    assert_eq!(PollOnce(&mut fut).await, Poll::Pending);
    assert_eq!(rx.recv_async().await, Ok("Hello!"));
    assert_eq!(PollOnce(&mut fut).await, Poll::Ready(Ok(())));
}

#[tokio::test]
async fn sync_send_bounded_wait_resume() {
    let (tx, rx) = barrage::new(Some(1));
    tx.send("Hello!").unwrap();
    let mut fut = tx.send_async("Hello!");
    assert_eq!(PollOnce(&mut fut).await, Poll::Pending);
    assert_eq!(rx.recv_async().await, Ok("Hello!"));
    assert_eq!(PollOnce(&mut fut).await, Poll::Ready(Ok(())));
}

#[tokio::test(max_threads = 4)]
async fn no_reorder() {
    let (tx, rx) = barrage::new(Some(1000));

    let mut handles = Vec::new();

    for _ in 0..4 {
        let rx = rx.clone();
        let mut cur = 0;

        let task = tokio::spawn(async move {
            while let Ok(n) = rx.recv_async().await {
                assert_eq!(n, cur);
                cur += 1;
            }
        });
        handles.push(task);
    }

    let task = tokio::spawn(async move {
        for i in 0..10_000usize {
            tx.send_async(i).await.unwrap();
        }
    });
    handles.push(task);
    drop(rx);

    for task in handles {
        task.await.unwrap();
    }
}

// -- Tests from loom.rs adapted to run without loom --

#[test]
fn broadcast_send_threaded() {
    let (tx1, rx) = barrage::bounded(2);
    let tx1 = Arc::new(tx1);
    let tx2 = tx1.clone();

    let th1 = thread::spawn(move || {
        assert_ok!(tx1.send("one"));
        assert_ok!(tx1.send("two"));
        assert_ok!(tx1.send("three"));
    });

    let th2 = thread::spawn(move || {
        tokio_test::block_on(async {
            assert_ok!(tx2.send_async("inye").await);
            assert_ok!(tx2.send_async("zimbini").await);
            assert_ok!(tx2.send_async("zintathu").await);
        });
    });

    tokio_test::block_on(async {
        let mut num: usize = 0;
        loop {
            match rx.recv_async().await {
                Ok(_) => num += 1,
                Err(_) => break,
            }
        }
        assert_eq!(num, 6);
    });

    assert_ok!(th1.join());
    assert_ok!(th2.join());
}

#[test]
fn drop_rx() {
    let (tx, rx1) = barrage::bounded(16);
    let rx2 = rx1.clone();

    let th1 = thread::spawn(move || {
        tokio_test::block_on(async {
            let v = assert_ok!(rx1.recv_async().await);
            assert_eq!(v, "one");

            let v = assert_ok!(rx1.recv_async().await);
            assert_eq!(v, "two");

            let v = assert_ok!(rx1.recv_async().await);
            assert_eq!(v, "three");

            assert!(rx1.recv_async().await.is_err());
        });
    });

    let th2 = thread::spawn(move || {
        drop(rx2);
    });

    assert_ok!(tx.send("one"));
    assert_ok!(tx.send("two"));
    assert_ok!(tx.send("three"));
    drop(tx);

    assert_ok!(th1.join());
    assert_ok!(th2.join());
}

#[test]
fn shared_receiver_receives_once() {
    let (tx, rx) = barrage::unbounded();
    let shared1 = rx.clone().into_shared();
    let shared2 = shared1.clone();

    tx.try_send("Hello!").unwrap();
    assert_eq!(shared1.try_recv(), Ok(Some("Hello!")));
    assert_eq!(shared2.try_recv(), Ok(None));
    assert_eq!(rx.try_recv(), Ok(Some("Hello!")));
}

#[test]
fn shared_receiver_same_mailbox() {
    let (_, rx) = barrage::unbounded::<()>();
    let shared_a_1 = rx.clone().into_shared();
    let shared_a_2 = shared_a_1.clone();
    let shared_b = rx.into_shared();

    assert!(shared_a_1.same_mailbox(&shared_a_2));
    assert!(!shared_a_1.same_mailbox(&shared_b));
}

#[test]
fn shared_receiver_drop() {
    let (tx, rx) = barrage::unbounded();
    let shared1 = rx.into_shared();
    let shared2 = shared1.clone();

    tx.try_send("Hello!").unwrap();
    assert_eq!(shared1.try_recv(), Ok(Some("Hello!")));
    assert_eq!(shared2.try_recv(), Ok(None));

    drop(shared2);

    tx.try_send("Hello2!").unwrap();
    assert_eq!(shared1.try_recv(), Ok(Some("Hello2!")));

    drop(shared1);

    assert!(tx.try_send("Hello3!").is_err());
}

#[test]
fn shared_receiver_upgrade() {
    let (tx, rx) = barrage::unbounded();
    let shared1 = rx.into_shared();
    let rx2 = shared1.clone().upgrade();

    tx.try_send("Hello!").unwrap();
    assert_eq!(shared1.try_recv(), Ok(Some("Hello!")));
    assert_eq!(rx2.try_recv(), Ok(Some("Hello!")));
}