David LeGare | 47ef9cb | 2022-03-02 00:19:32 +0000 | [diff] [blame] | 1 | use std::iter; |
| 2 | use std::sync::Arc; |
| 3 | |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 4 | use futures::channel::mpsc; |
| 5 | use futures::executor::block_on; |
| 6 | use futures::future::{self, Future}; |
David LeGare | 47ef9cb | 2022-03-02 00:19:32 +0000 | [diff] [blame] | 7 | use futures::lock::Mutex; |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 8 | use futures::sink::SinkExt; |
| 9 | use futures::stream::{self, StreamExt}; |
| 10 | use futures::task::Poll; |
David LeGare | 47ef9cb | 2022-03-02 00:19:32 +0000 | [diff] [blame] | 11 | use futures::{ready, FutureExt}; |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 12 | use futures_test::task::noop_context; |
| 13 | |
Jason Macnak | 3d406bb | 2020-03-19 21:05:06 +0000 | [diff] [blame] | 14 | #[test] |
| 15 | fn select() { |
| 16 | fn select_and_compare(a: Vec<u32>, b: Vec<u32>, expected: Vec<u32>) { |
| 17 | let a = stream::iter(a); |
| 18 | let b = stream::iter(b); |
| 19 | let vec = block_on(stream::select(a, b).collect::<Vec<_>>()); |
| 20 | assert_eq!(vec, expected); |
| 21 | } |
| 22 | |
| 23 | select_and_compare(vec![1, 2, 3], vec![4, 5, 6], vec![1, 4, 2, 5, 3, 6]); |
| 24 | select_and_compare(vec![1, 2, 3], vec![4, 5], vec![1, 4, 2, 5, 3]); |
| 25 | select_and_compare(vec![1, 2], vec![4, 5, 6], vec![1, 4, 2, 5, 6]); |
| 26 | } |
| 27 | |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 28 | #[test] |
| 29 | fn flat_map() { |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 30 | block_on(async { |
| 31 | let st = |
| 32 | stream::iter(vec![stream::iter(0..=4u8), stream::iter(6..=10), stream::iter(0..=2)]); |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 33 | |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 34 | let values: Vec<_> = |
| 35 | st.flat_map(|s| s.filter(|v| futures::future::ready(v % 2 == 0))).collect().await; |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 36 | |
| 37 | assert_eq!(values, vec![0, 2, 4, 6, 8, 10, 0, 2]); |
| 38 | }); |
| 39 | } |
| 40 | |
Jason Macnak | 3d406bb | 2020-03-19 21:05:06 +0000 | [diff] [blame] | 41 | #[test] |
| 42 | fn scan() { |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 43 | block_on(async { |
| 44 | let values = stream::iter(vec![1u8, 2, 3, 4, 6, 8, 2]) |
| 45 | .scan(1, |state, e| { |
| 46 | *state += 1; |
| 47 | futures::future::ready(if e < *state { Some(e) } else { None }) |
| 48 | }) |
| 49 | .collect::<Vec<_>>() |
| 50 | .await; |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 51 | |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 52 | assert_eq!(values, vec![1u8, 2, 3, 4]); |
Jason Macnak | 3d406bb | 2020-03-19 21:05:06 +0000 | [diff] [blame] | 53 | }); |
| 54 | } |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 55 | |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 56 | #[test] |
David LeGare | 47ef9cb | 2022-03-02 00:19:32 +0000 | [diff] [blame] | 57 | fn flatten_unordered() { |
| 58 | use futures::executor::block_on; |
| 59 | use futures::stream::*; |
| 60 | use futures::task::*; |
| 61 | use std::convert::identity; |
| 62 | use std::pin::Pin; |
| 63 | use std::thread; |
| 64 | use std::time::Duration; |
| 65 | |
| 66 | struct DataStream { |
| 67 | data: Vec<u8>, |
| 68 | polled: bool, |
| 69 | wake_immediately: bool, |
| 70 | } |
| 71 | |
| 72 | impl Stream for DataStream { |
| 73 | type Item = u8; |
| 74 | |
| 75 | fn poll_next(mut self: Pin<&mut Self>, ctx: &mut Context) -> Poll<Option<Self::Item>> { |
| 76 | if !self.polled { |
| 77 | if !self.wake_immediately { |
| 78 | let waker = ctx.waker().clone(); |
| 79 | let sleep_time = |
| 80 | Duration::from_millis(*self.data.first().unwrap_or(&0) as u64 / 10); |
| 81 | thread::spawn(move || { |
| 82 | thread::sleep(sleep_time); |
| 83 | waker.wake_by_ref(); |
| 84 | }); |
| 85 | } else { |
| 86 | ctx.waker().wake_by_ref(); |
| 87 | } |
| 88 | self.polled = true; |
| 89 | Poll::Pending |
| 90 | } else { |
| 91 | self.polled = false; |
| 92 | Poll::Ready(self.data.pop()) |
| 93 | } |
| 94 | } |
| 95 | } |
| 96 | |
| 97 | struct Interchanger { |
| 98 | polled: bool, |
| 99 | base: u8, |
| 100 | wake_immediately: bool, |
| 101 | } |
| 102 | |
| 103 | impl Stream for Interchanger { |
| 104 | type Item = DataStream; |
| 105 | |
| 106 | fn poll_next(mut self: Pin<&mut Self>, ctx: &mut Context) -> Poll<Option<Self::Item>> { |
| 107 | if !self.polled { |
| 108 | self.polled = true; |
| 109 | if !self.wake_immediately { |
| 110 | let waker = ctx.waker().clone(); |
| 111 | let sleep_time = Duration::from_millis(self.base as u64); |
| 112 | thread::spawn(move || { |
| 113 | thread::sleep(sleep_time); |
| 114 | waker.wake_by_ref(); |
| 115 | }); |
| 116 | } else { |
| 117 | ctx.waker().wake_by_ref(); |
| 118 | } |
| 119 | Poll::Pending |
| 120 | } else { |
| 121 | let data: Vec<_> = (0..6).rev().map(|v| v + self.base * 6).collect(); |
| 122 | self.base += 1; |
| 123 | self.polled = false; |
| 124 | Poll::Ready(Some(DataStream { |
| 125 | polled: false, |
| 126 | data, |
| 127 | wake_immediately: self.wake_immediately && self.base % 2 == 0, |
| 128 | })) |
| 129 | } |
| 130 | } |
| 131 | } |
| 132 | |
| 133 | // basic behaviour |
| 134 | { |
| 135 | block_on(async { |
| 136 | let st = stream::iter(vec![ |
| 137 | stream::iter(0..=4u8), |
| 138 | stream::iter(6..=10), |
| 139 | stream::iter(10..=12), |
| 140 | ]); |
| 141 | |
| 142 | let fl_unordered = st.flatten_unordered(3).collect::<Vec<_>>().await; |
| 143 | |
| 144 | assert_eq!(fl_unordered, vec![0, 6, 10, 1, 7, 11, 2, 8, 12, 3, 9, 4, 10]); |
| 145 | }); |
| 146 | |
| 147 | block_on(async { |
| 148 | let st = stream::iter(vec![ |
| 149 | stream::iter(0..=4u8), |
| 150 | stream::iter(6..=10), |
| 151 | stream::iter(0..=2), |
| 152 | ]); |
| 153 | |
| 154 | let mut fm_unordered = st |
| 155 | .flat_map_unordered(1, |s| s.filter(|v| futures::future::ready(v % 2 == 0))) |
| 156 | .collect::<Vec<_>>() |
| 157 | .await; |
| 158 | |
| 159 | fm_unordered.sort_unstable(); |
| 160 | |
| 161 | assert_eq!(fm_unordered, vec![0, 0, 2, 2, 4, 6, 8, 10]); |
| 162 | }); |
| 163 | } |
| 164 | |
| 165 | // wake up immediately |
| 166 | { |
| 167 | block_on(async { |
| 168 | let mut fl_unordered = Interchanger { polled: false, base: 0, wake_immediately: true } |
| 169 | .take(10) |
| 170 | .map(|s| s.map(identity)) |
| 171 | .flatten_unordered(10) |
| 172 | .collect::<Vec<_>>() |
| 173 | .await; |
| 174 | |
| 175 | fl_unordered.sort_unstable(); |
| 176 | |
| 177 | assert_eq!(fl_unordered, (0..60).collect::<Vec<u8>>()); |
| 178 | }); |
| 179 | |
| 180 | block_on(async { |
| 181 | let mut fm_unordered = Interchanger { polled: false, base: 0, wake_immediately: true } |
| 182 | .take(10) |
| 183 | .flat_map_unordered(10, |s| s.map(identity)) |
| 184 | .collect::<Vec<_>>() |
| 185 | .await; |
| 186 | |
| 187 | fm_unordered.sort_unstable(); |
| 188 | |
| 189 | assert_eq!(fm_unordered, (0..60).collect::<Vec<u8>>()); |
| 190 | }); |
| 191 | } |
| 192 | |
| 193 | // wake up after delay |
| 194 | { |
| 195 | block_on(async { |
| 196 | let mut fl_unordered = Interchanger { polled: false, base: 0, wake_immediately: false } |
| 197 | .take(10) |
| 198 | .map(|s| s.map(identity)) |
| 199 | .flatten_unordered(10) |
| 200 | .collect::<Vec<_>>() |
| 201 | .await; |
| 202 | |
| 203 | fl_unordered.sort_unstable(); |
| 204 | |
| 205 | assert_eq!(fl_unordered, (0..60).collect::<Vec<u8>>()); |
| 206 | }); |
| 207 | |
| 208 | block_on(async { |
| 209 | let mut fm_unordered = Interchanger { polled: false, base: 0, wake_immediately: false } |
| 210 | .take(10) |
| 211 | .flat_map_unordered(10, |s| s.map(identity)) |
| 212 | .collect::<Vec<_>>() |
| 213 | .await; |
| 214 | |
| 215 | fm_unordered.sort_unstable(); |
| 216 | |
| 217 | assert_eq!(fm_unordered, (0..60).collect::<Vec<u8>>()); |
| 218 | }); |
| 219 | |
| 220 | block_on(async { |
| 221 | let (mut fm_unordered, mut fl_unordered) = futures_util::join!( |
| 222 | Interchanger { polled: false, base: 0, wake_immediately: false } |
| 223 | .take(10) |
| 224 | .flat_map_unordered(10, |s| s.map(identity)) |
| 225 | .collect::<Vec<_>>(), |
| 226 | Interchanger { polled: false, base: 0, wake_immediately: false } |
| 227 | .take(10) |
| 228 | .map(|s| s.map(identity)) |
| 229 | .flatten_unordered(10) |
| 230 | .collect::<Vec<_>>() |
| 231 | ); |
| 232 | |
| 233 | fm_unordered.sort_unstable(); |
| 234 | fl_unordered.sort_unstable(); |
| 235 | |
| 236 | assert_eq!(fm_unordered, fl_unordered); |
| 237 | assert_eq!(fm_unordered, (0..60).collect::<Vec<u8>>()); |
| 238 | }); |
| 239 | } |
| 240 | |
| 241 | // waker panics |
| 242 | { |
| 243 | let stream = Arc::new(Mutex::new( |
| 244 | Interchanger { polled: false, base: 0, wake_immediately: true } |
| 245 | .take(10) |
| 246 | .flat_map_unordered(10, |s| s.map(identity)), |
| 247 | )); |
| 248 | |
| 249 | struct PanicWaker; |
| 250 | |
| 251 | impl ArcWake for PanicWaker { |
| 252 | fn wake_by_ref(_arc_self: &Arc<Self>) { |
| 253 | panic!("WAKE UP"); |
| 254 | } |
| 255 | } |
| 256 | |
| 257 | std::thread::spawn({ |
| 258 | let stream = stream.clone(); |
| 259 | move || { |
| 260 | let mut st = poll_fn(|cx| { |
| 261 | let mut lock = ready!(stream.lock().poll_unpin(cx)); |
| 262 | |
| 263 | let panic_waker = waker(Arc::new(PanicWaker)); |
| 264 | let mut panic_cx = Context::from_waker(&panic_waker); |
| 265 | let _ = ready!(lock.poll_next_unpin(&mut panic_cx)); |
| 266 | |
| 267 | Poll::Ready(Some(())) |
| 268 | }); |
| 269 | |
| 270 | block_on(st.next()) |
| 271 | } |
| 272 | }) |
| 273 | .join() |
| 274 | .unwrap_err(); |
| 275 | |
| 276 | block_on(async move { |
| 277 | let mut values: Vec<_> = stream.lock().await.by_ref().collect().await; |
| 278 | values.sort_unstable(); |
| 279 | |
| 280 | assert_eq!(values, (0..60).collect::<Vec<u8>>()); |
| 281 | }); |
| 282 | } |
| 283 | |
| 284 | // stream panics |
| 285 | { |
| 286 | let st = stream::iter(iter::once( |
| 287 | once(Box::pin(async { panic!("Polled") })).left_stream::<DataStream>(), |
| 288 | )) |
| 289 | .chain( |
| 290 | Interchanger { polled: false, base: 0, wake_immediately: true } |
| 291 | .map(|stream| stream.right_stream()) |
| 292 | .take(10), |
| 293 | ); |
| 294 | |
| 295 | let stream = Arc::new(Mutex::new(st.flatten_unordered(10))); |
| 296 | |
| 297 | std::thread::spawn({ |
| 298 | let stream = stream.clone(); |
| 299 | move || { |
| 300 | let mut st = poll_fn(|cx| { |
| 301 | let mut lock = ready!(stream.lock().poll_unpin(cx)); |
| 302 | let data = ready!(lock.poll_next_unpin(cx)); |
| 303 | |
| 304 | Poll::Ready(data) |
| 305 | }); |
| 306 | |
| 307 | block_on(st.next()) |
| 308 | } |
| 309 | }) |
| 310 | .join() |
| 311 | .unwrap_err(); |
| 312 | |
| 313 | block_on(async move { |
| 314 | let mut values: Vec<_> = stream.lock().await.by_ref().collect().await; |
| 315 | values.sort_unstable(); |
| 316 | |
| 317 | assert_eq!(values, (0..60).collect::<Vec<u8>>()); |
| 318 | }); |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | #[test] |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 323 | fn take_until() { |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 324 | fn make_stop_fut(stop_on: u32) -> impl Future<Output = ()> { |
| 325 | let mut i = 0; |
| 326 | future::poll_fn(move |_cx| { |
| 327 | i += 1; |
| 328 | if i <= stop_on { |
| 329 | Poll::Pending |
| 330 | } else { |
| 331 | Poll::Ready(()) |
| 332 | } |
| 333 | }) |
| 334 | } |
| 335 | |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 336 | block_on(async { |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 337 | // Verify stopping works: |
| 338 | let stream = stream::iter(1u32..=10); |
| 339 | let stop_fut = make_stop_fut(5); |
| 340 | |
| 341 | let stream = stream.take_until(stop_fut); |
| 342 | let last = stream.fold(0, |_, i| async move { i }).await; |
| 343 | assert_eq!(last, 5); |
| 344 | |
| 345 | // Verify take_future() works: |
| 346 | let stream = stream::iter(1..=10); |
| 347 | let stop_fut = make_stop_fut(5); |
| 348 | |
| 349 | let mut stream = stream.take_until(stop_fut); |
| 350 | |
| 351 | assert_eq!(stream.next().await, Some(1)); |
| 352 | assert_eq!(stream.next().await, Some(2)); |
| 353 | |
| 354 | stream.take_future(); |
| 355 | |
| 356 | let last = stream.fold(0, |_, i| async move { i }).await; |
| 357 | assert_eq!(last, 10); |
| 358 | |
| 359 | // Verify take_future() returns None if stream is stopped: |
| 360 | let stream = stream::iter(1u32..=10); |
| 361 | let stop_fut = make_stop_fut(1); |
| 362 | let mut stream = stream.take_until(stop_fut); |
| 363 | assert_eq!(stream.next().await, Some(1)); |
| 364 | assert_eq!(stream.next().await, None); |
| 365 | assert!(stream.take_future().is_none()); |
| 366 | |
| 367 | // Verify TakeUntil is fused: |
| 368 | let mut i = 0; |
| 369 | let stream = stream::poll_fn(move |_cx| { |
| 370 | i += 1; |
| 371 | match i { |
| 372 | 1 => Poll::Ready(Some(1)), |
| 373 | 2 => Poll::Ready(None), |
| 374 | _ => panic!("TakeUntil not fused"), |
| 375 | } |
| 376 | }); |
| 377 | |
| 378 | let stop_fut = make_stop_fut(1); |
| 379 | let mut stream = stream.take_until(stop_fut); |
| 380 | assert_eq!(stream.next().await, Some(1)); |
| 381 | assert_eq!(stream.next().await, None); |
| 382 | assert_eq!(stream.next().await, None); |
| 383 | }); |
| 384 | } |
| 385 | |
| 386 | #[test] |
| 387 | #[should_panic] |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 388 | fn chunks_panic_on_cap_zero() { |
| 389 | let (_, rx1) = mpsc::channel::<()>(1); |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 390 | |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 391 | let _ = rx1.chunks(0); |
| 392 | } |
| 393 | |
| 394 | #[test] |
| 395 | #[should_panic] |
| 396 | fn ready_chunks_panic_on_cap_zero() { |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 397 | let (_, rx1) = mpsc::channel::<()>(1); |
| 398 | |
| 399 | let _ = rx1.ready_chunks(0); |
| 400 | } |
| 401 | |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 402 | #[test] |
| 403 | fn ready_chunks() { |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 404 | let (mut tx, rx1) = mpsc::channel::<i32>(16); |
| 405 | |
| 406 | let mut s = rx1.ready_chunks(2); |
| 407 | |
| 408 | let mut cx = noop_context(); |
| 409 | assert!(s.next().poll_unpin(&mut cx).is_pending()); |
| 410 | |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 411 | block_on(async { |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 412 | tx.send(1).await.unwrap(); |
| 413 | |
| 414 | assert_eq!(s.next().await.unwrap(), vec![1]); |
| 415 | tx.send(2).await.unwrap(); |
| 416 | tx.send(3).await.unwrap(); |
| 417 | tx.send(4).await.unwrap(); |
Joel Galenson | 2259736 | 2021-05-19 15:06:18 -0700 | [diff] [blame] | 418 | assert_eq!(s.next().await.unwrap(), vec![2, 3]); |
Haibo Huang | 67f2b76 | 2020-05-08 19:24:38 -0700 | [diff] [blame] | 419 | assert_eq!(s.next().await.unwrap(), vec![4]); |
| 420 | }); |
Chih-Hung Hsieh | 32ee67e | 2020-10-25 23:16:20 -0700 | [diff] [blame] | 421 | } |