tests/ui/generator/print/generator-print-verbose-1.rs

   1 // compile-flags: -Zverbose
   2
   3 // Same as: tests/ui/generator/issue-68112.stderr
   4
   5 #![feature(generators, generator_trait)]
   6
   7 use std::{
   8     cell::RefCell,
   9     sync::Arc,
  10     pin::Pin,
  11     ops::{Generator, GeneratorState},
  12 };
  13
  14 pub struct Ready<T>(Option<T>);
  15 impl<T: Unpin> Generator<()> for Ready<T> {
  16     type Return = T;
  17     type Yield = ();
  18     fn resume(mut self: Pin<&mut Self>, _args: ()) -> GeneratorState<(), T> {
  19         GeneratorState::Complete(self.0.take().unwrap())
  20     }
  21 }
  22 pub fn make_gen1<T>(t: T) -> Ready<T> {
  23     Ready(Some(t))
  24 }
  25
  26 fn require_send(_: impl Send) {}
  27
  28 fn make_non_send_generator() -> impl Generator<Return = Arc<RefCell<i32>>> {
  29     make_gen1(Arc::new(RefCell::new(0)))
  30 }
  31
  32 fn test1() {
  33     let send_gen = || {
  34         let _non_send_gen = make_non_send_generator();
  35         yield;
  36     };
  37     require_send(send_gen);
  38     //~^ ERROR generator cannot be sent between threads
  39 }
  40
  41 pub fn make_gen2<T>(t: T) -> impl Generator<Return = T> {
  42     || {
  43         yield;
  44         t
  45     }
  46 }
  47 fn make_non_send_generator2() -> impl Generator<Return = Arc<RefCell<i32>>> {
  48     make_gen2(Arc::new(RefCell::new(0)))
  49 }
  50
  51 fn test2() {
  52     let send_gen = || {
  53         let _non_send_gen = make_non_send_generator2();
  54         yield;
  55     };
  56     require_send(send_gen);
  57     //~^ ERROR `RefCell<i32>` cannot be shared between threads safely
  58 }
  59
  60 fn main() {}