tests/run-pass/time.rs

   1 // compile-flags: -Zmiri-disable-isolation
   2
   3 use std::time::{SystemTime, Instant, Duration};
   4
   5 fn duration_sanity(diff: Duration) {
   6     // On my laptop, I observed times around 15-40ms. Add 10x lee-way both ways.
   7     assert!(diff.as_millis() > 1);
   8     assert!(diff.as_millis() < 500);
   9 }
  10
  11 #[cfg(unix)]
  12 fn test_sleep() {
  13     let before = Instant::now();
  14     std::thread::sleep(Duration::from_millis(100));
  15     let after = Instant::now();
  16     assert!((after - before).as_millis() >= 100);
  17 }
  18
  19 fn main() {
  20     // Check `SystemTime`.
  21     let now1 = SystemTime::now();
  22     let seconds_since_epoch = now1.duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
  23     let years_since_epoch = seconds_since_epoch / 3600 / 24 / 365;
  24     let year = 1970 + years_since_epoch;
  25     assert!(2020 <= year && year < 2100);
  26     // Do some work to make time pass.
  27     for _ in 0..10 { drop(vec![42]); }
  28     let now2 = SystemTime::now();
  29     assert!(now2 > now1);
  30     // Sanity-check the difference we got.
  31     let diff = now2.duration_since(now1).unwrap();
  32     assert_eq!(now1 + diff, now2);
  33     assert_eq!(now2 - diff, now1);
  34     duration_sanity(diff);
  35
  36     // Check `Instant`.
  37     let now1 = Instant::now();
  38     // Do some work to make time pass.
  39     for _ in 0..10 { drop(vec![42]); }
  40     let now2 = Instant::now();
  41     assert!(now2 > now1);
  42     // Sanity-check the difference we got.
  43     let diff = now2.duration_since(now1);
  44     assert_eq!(now1 + diff, now2);
  45     assert_eq!(now2 - diff, now1);
  46     duration_sanity(diff);
  47
  48     #[cfg(unix)]
  49     test_sleep();
  50 }