tests/ui/generator/conditional-drop.rs

   1 // run-pass
   2
   3 // revisions: default nomiropt
   4 //[nomiropt]compile-flags: -Z mir-opt-level=0
   5
   6 #![feature(generators, generator_trait)]
   7
   8 use std::ops::Generator;
   9 use std::pin::Pin;
  10 use std::sync::atomic::{AtomicUsize, Ordering};
  11
  12 static A: AtomicUsize = AtomicUsize::new(0);
  13
  14 struct B;
  15
  16 impl Drop for B {
  17     fn drop(&mut self) {
  18         A.fetch_add(1, Ordering::SeqCst);
  19     }
  20 }
  21
  22
  23 fn test() -> bool { true }
  24 fn test2() -> bool { false }
  25
  26 fn main() {
  27     t1();
  28     t2();
  29 }
  30
  31 fn t1() {
  32     let mut a = || {
  33         let b = B;
  34         if test() {
  35             drop(b);
  36         }
  37         yield;
  38     };
  39
  40     let n = A.load(Ordering::SeqCst);
  41     Pin::new(&mut a).resume(());
  42     assert_eq!(A.load(Ordering::SeqCst), n + 1);
  43     Pin::new(&mut a).resume(());
  44     assert_eq!(A.load(Ordering::SeqCst), n + 1);
  45 }
  46
  47 fn t2() {
  48     let mut a = || {
  49         let b = B;
  50         if test2() {
  51             drop(b);
  52         }
  53         yield;
  54     };
  55
  56     let n = A.load(Ordering::SeqCst);
  57     Pin::new(&mut a).resume(());
  58     assert_eq!(A.load(Ordering::SeqCst), n);
  59     Pin::new(&mut a).resume(());
  60     assert_eq!(A.load(Ordering::SeqCst), n + 1);
  61 }