vendor/crossbeam-utils/tests/wait_group.rs

   1 extern crate crossbeam_utils;
   2
   3 use std::sync::mpsc;
   4 use std::thread;
   5 use std::time::Duration;
   6
   7 use crossbeam_utils::sync::WaitGroup;
   8
   9 const THREADS: usize = 10;
  10
  11 #[test]
  12 fn wait() {
  13     let wg = WaitGroup::new();
  14     let (tx, rx) = mpsc::channel();
  15
  16     for _ in 0..THREADS {
  17         let wg = wg.clone();
  18         let tx = tx.clone();
  19
  20         thread::spawn(move || {
  21             wg.wait();
  22             tx.send(()).unwrap();
  23         });
  24     }
  25
  26     thread::sleep(Duration::from_millis(100));
  27
  28     // At this point, all spawned threads should be blocked, so we shouldn't get anything from the
  29     // channel.
  30     assert!(rx.try_recv().is_err());
  31
  32     wg.wait();
  33
  34     // Now, the wait group is cleared and we should receive messages.
  35     for _ in 0..THREADS {
  36         rx.recv().unwrap();
  37     }
  38 }
  39
  40 #[test]
  41 fn wait_and_drop() {
  42     let wg = WaitGroup::new();
  43     let (tx, rx) = mpsc::channel();
  44
  45     for _ in 0..THREADS {
  46         let wg = wg.clone();
  47         let tx = tx.clone();
  48
  49         thread::spawn(move || {
  50             thread::sleep(Duration::from_millis(100));
  51             tx.send(()).unwrap();
  52             drop(wg);
  53         });
  54     }
  55
  56     // At this point, all spawned threads should be sleeping, so we shouldn't get anything from the
  57     // channel.
  58     assert!(rx.try_recv().is_err());
  59
  60     wg.wait();
  61
  62     // Now, the wait group is cleared and we should receive messages.
  63     for _ in 0..THREADS {
  64         rx.try_recv().unwrap();
  65     }
  66 }