summaryrefslogtreecommitdiffstats
path: root/third_party/rust/tokio/tests/sync_mutex_owned.rs
blob: 2ce15de5b9d969e0d46b16eee643b72279fd565a (plain)
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
#![warn(rust_2018_idioms)]
#![cfg(feature = "sync")]

#[cfg(target_arch = "wasm32")]
use wasm_bindgen_test::wasm_bindgen_test as test;
#[cfg(target_arch = "wasm32")]
use wasm_bindgen_test::wasm_bindgen_test as maybe_tokio_test;

#[cfg(not(target_arch = "wasm32"))]
use tokio::test as maybe_tokio_test;

use tokio::sync::Mutex;
use tokio_test::task::spawn;
use tokio_test::{assert_pending, assert_ready};

use std::sync::Arc;

#[test]
fn straight_execution() {
    let l = Arc::new(Mutex::new(100));

    {
        let mut t = spawn(l.clone().lock_owned());
        let mut g = assert_ready!(t.poll());
        assert_eq!(&*g, &100);
        *g = 99;
    }
    {
        let mut t = spawn(l.clone().lock_owned());
        let mut g = assert_ready!(t.poll());
        assert_eq!(&*g, &99);
        *g = 98;
    }
    {
        let mut t = spawn(l.lock_owned());
        let g = assert_ready!(t.poll());
        assert_eq!(&*g, &98);
    }
}

#[test]
fn readiness() {
    let l = Arc::new(Mutex::new(100));
    let mut t1 = spawn(l.clone().lock_owned());
    let mut t2 = spawn(l.lock_owned());

    let g = assert_ready!(t1.poll());

    // We can't now acquire the lease since it's already held in g
    assert_pending!(t2.poll());

    // But once g unlocks, we can acquire it
    drop(g);
    assert!(t2.is_woken());
    assert_ready!(t2.poll());
}

/// Ensure a mutex is unlocked if a future holding the lock
/// is aborted prematurely.
#[tokio::test]
#[cfg(feature = "full")]
async fn aborted_future_1() {
    use std::time::Duration;
    use tokio::time::{interval, timeout};

    let m1: Arc<Mutex<usize>> = Arc::new(Mutex::new(0));
    {
        let m2 = m1.clone();
        // Try to lock mutex in a future that is aborted prematurely
        timeout(Duration::from_millis(1u64), async move {
            let iv = interval(Duration::from_millis(1000));
            tokio::pin!(iv);
            m2.lock_owned().await;
            iv.as_mut().tick().await;
            iv.as_mut().tick().await;
        })
        .await
        .unwrap_err();
    }
    // This should succeed as there is no lock left for the mutex.
    timeout(Duration::from_millis(1u64), async move {
        m1.lock_owned().await;
    })
    .await
    .expect("Mutex is locked");
}

/// This test is similar to `aborted_future_1` but this time the
/// aborted future is waiting for the lock.
#[tokio::test]
#[cfg(feature = "full")]
async fn aborted_future_2() {
    use std::time::Duration;
    use tokio::time::timeout;

    let m1: Arc<Mutex<usize>> = Arc::new(Mutex::new(0));
    {
        // Lock mutex
        let _lock = m1.clone().lock_owned().await;
        {
            let m2 = m1.clone();
            // Try to lock mutex in a future that is aborted prematurely
            timeout(Duration::from_millis(1u64), async move {
                m2.lock_owned().await;
            })
            .await
            .unwrap_err();
        }
    }
    // This should succeed as there is no lock left for the mutex.
    timeout(Duration::from_millis(1u64), async move {
        m1.lock_owned().await;
    })
    .await
    .expect("Mutex is locked");
}

#[test]
fn try_lock_owned() {
    let m: Arc<Mutex<usize>> = Arc::new(Mutex::new(0));
    {
        let g1 = m.clone().try_lock_owned();
        assert!(g1.is_ok());
        let g2 = m.clone().try_lock_owned();
        assert!(!g2.is_ok());
    }
    let g3 = m.try_lock_owned();
    assert!(g3.is_ok());
}

#[maybe_tokio_test]
async fn debug_format() {
    let s = "debug";
    let m = Arc::new(Mutex::new(s.to_string()));
    assert_eq!(format!("{:?}", s), format!("{:?}", m.lock_owned().await));
}