src/test/ui/issues/issue-33387.rs

   1 // run-pass
   2 #![feature(rustc_attrs)]
   3
   4 use std::sync::Arc;
   5
   6 trait Foo {
   7     fn get(&self) -> [u8; 2];
   8 }
   9
  10 impl Foo for [u8; 2] {
  11     fn get(&self) -> [u8; 2] {
  12         *self
  13     }
  14 }
  15
  16 struct Bar<T: ?Sized>(T);
  17
  18 fn unsize_fat_ptr<'a>(x: &'a Bar<dyn Foo + Send + 'a>) -> &'a Bar<dyn Foo + 'a> {
  19     x
  20 }
  21
  22 fn unsize_nested_fat_ptr(x: Arc<dyn Foo + Send>) -> Arc<dyn Foo> {
  23     x
  24 }
  25
  26 fn main() {
  27     let x: Box<Bar<dyn Foo + Send>> = Box::new(Bar([1,2]));
  28     assert_eq!(unsize_fat_ptr(&*x).0.get(), [1, 2]);
  29
  30     let x: Arc<dyn Foo + Send> = Arc::new([3, 4]);
  31     assert_eq!(unsize_nested_fat_ptr(x).get(), [3, 4]);
  32 }