rust/library/core/tests/pin.rs
Christiaan Dirkx e3c6e46168 Make some methods of Pin<&mut T> unstable const
Make the following methods unstable const under the `const_pin` feature:
- `into_ref`
- `get_mut`
- `get_unchecked_mut`
2020-09-18 19:23:50 +02:00

31 lines
1 KiB
Rust

use core::pin::Pin;
#[test]
fn pin_const() {
// test that the methods of `Pin` are usable in a const context
const POINTER: &'static usize = &2;
const PINNED: Pin<&'static usize> = Pin::new(POINTER);
const PINNED_UNCHECKED: Pin<&'static usize> = unsafe { Pin::new_unchecked(POINTER) };
assert_eq!(PINNED_UNCHECKED, PINNED);
const INNER: &'static usize = Pin::into_inner(PINNED);
assert_eq!(INNER, POINTER);
const INNER_UNCHECKED: &'static usize = unsafe { Pin::into_inner_unchecked(PINNED) };
assert_eq!(INNER_UNCHECKED, POINTER);
const REF: &'static usize = PINNED.get_ref();
assert_eq!(REF, POINTER);
// Note: `pin_mut_const` tests that the methods of `Pin<&mut T>` are usable in a const context.
// A const fn is used because `&mut` is not (yet) usable in constants.
const fn pin_mut_const() {
let _ = Pin::new(&mut 2).into_ref();
let _ = Pin::new(&mut 2).get_mut();
let _ = unsafe { Pin::new(&mut 2).get_unchecked_mut() };
}
pin_mut_const();
}