tests/ui/drop/drop-trait-enum.rs

   1 // run-pass
   2 #![allow(dead_code)]
   3 #![allow(unused_assignments)]
   4 #![allow(unused_variables)]
   5 // ignore-emscripten no threads support
   6 // needs-unwind
   7
   8 use std::thread;
   9 use std::sync::mpsc::{channel, Sender};
  10
  11 #[derive(PartialEq, Debug)]
  12 enum Message {
  13     Dropped,
  14     DestructorRan
  15 }
  16
  17 struct SendOnDrop {
  18     sender: Sender<Message>
  19 }
  20
  21 impl Drop for SendOnDrop {
  22     fn drop(&mut self) {
  23         self.sender.send(Message::Dropped).unwrap();
  24     }
  25 }
  26
  27 enum Foo {
  28     SimpleVariant(Sender<Message>),
  29     NestedVariant(Box<usize>, SendOnDrop, Sender<Message>),
  30     FailingVariant { on_drop: SendOnDrop }
  31 }
  32
  33 impl Drop for Foo {
  34     fn drop(&mut self) {
  35         match self {
  36             &mut Foo::SimpleVariant(ref mut sender) => {
  37                 sender.send(Message::DestructorRan).unwrap();
  38             }
  39             &mut Foo::NestedVariant(_, _, ref mut sender) => {
  40                 sender.send(Message::DestructorRan).unwrap();
  41             }
  42             &mut Foo::FailingVariant { .. } => {
  43                 panic!("Failed");
  44             }
  45         }
  46     }
  47 }
  48
  49 pub fn main() {
  50     let (sender, receiver) = channel();
  51     {
  52         let v = Foo::SimpleVariant(sender);
  53     }
  54     assert_eq!(receiver.recv().unwrap(), Message::DestructorRan);
  55     assert_eq!(receiver.recv().ok(), None);
  56
  57     let (sender, receiver) = channel();
  58     {
  59         let v = Foo::NestedVariant(Box::new(42), SendOnDrop { sender: sender.clone() }, sender);
  60     }
  61     assert_eq!(receiver.recv().unwrap(), Message::DestructorRan);
  62     assert_eq!(receiver.recv().unwrap(), Message::Dropped);
  63     assert_eq!(receiver.recv().ok(), None);
  64
  65     let (sender, receiver) = channel();
  66     let t = thread::spawn(move|| {
  67         let v = Foo::FailingVariant { on_drop: SendOnDrop { sender: sender } };
  68     });
  69     assert_eq!(receiver.recv().unwrap(), Message::Dropped);
  70     assert_eq!(receiver.recv().ok(), None);
  71     drop(t.join());
  72
  73     let (sender, receiver) = channel();
  74     let t = {
  75         thread::spawn(move|| {
  76             let mut v = Foo::NestedVariant(Box::new(42), SendOnDrop {
  77                 sender: sender.clone()
  78             }, sender.clone());
  79             v = Foo::NestedVariant(Box::new(42),
  80                                    SendOnDrop { sender: sender.clone() },
  81                                    sender.clone());
  82             v = Foo::SimpleVariant(sender.clone());
  83             v = Foo::FailingVariant { on_drop: SendOnDrop { sender: sender } };
  84         })
  85     };
  86     assert_eq!(receiver.recv().unwrap(), Message::DestructorRan);
  87     assert_eq!(receiver.recv().unwrap(), Message::Dropped);
  88     assert_eq!(receiver.recv().unwrap(), Message::DestructorRan);
  89     assert_eq!(receiver.recv().unwrap(), Message::Dropped);
  90     assert_eq!(receiver.recv().unwrap(), Message::DestructorRan);
  91     assert_eq!(receiver.recv().unwrap(), Message::Dropped);
  92     assert_eq!(receiver.recv().ok(), None);
  93     drop(t.join());
  94 }