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// Currently this test doesn't actually check the output of the functions.
// It's only here for miri to check for any potential undefined behaviour.
// TODO: check function results
#[test]
fn test_transparent_wrapper() {
// An external type defined in a different crate.
#[derive(Debug, Copy, Clone, Default)]
struct Foreign(u8);
use bytemuck::TransparentWrapper;
#[derive(Debug, Copy, Clone)]
#[repr(transparent)]
struct Wrapper(Foreign);
unsafe impl TransparentWrapper<Foreign> for Wrapper {}
// Traits can be implemented on crate-local wrapper.
unsafe impl bytemuck::Zeroable for Wrapper {}
unsafe impl bytemuck::Pod for Wrapper {}
impl PartialEq<u8> for Foreign {
fn eq(&self, &other: &u8) -> bool {
self.0 == other
}
}
impl PartialEq<u8> for Wrapper {
fn eq(&self, &other: &u8) -> bool {
self.0 == other
}
}
let _: u8 = bytemuck::cast(Wrapper::wrap(Foreign::default()));
let _: Foreign = Wrapper::peel(bytemuck::cast(u8::default()));
let _: &u8 = bytemuck::cast_ref(Wrapper::wrap_ref(&Foreign::default()));
let _: &Foreign = Wrapper::peel_ref(bytemuck::cast_ref(&u8::default()));
let _: &mut u8 =
bytemuck::cast_mut(Wrapper::wrap_mut(&mut Foreign::default()));
let _: &mut Foreign =
Wrapper::peel_mut(bytemuck::cast_mut(&mut u8::default()));
let _: &[u8] =
bytemuck::cast_slice(Wrapper::wrap_slice(&[Foreign::default()]));
let _: &[Foreign] =
Wrapper::peel_slice(bytemuck::cast_slice(&[u8::default()]));
let _: &mut [u8] =
bytemuck::cast_slice_mut(Wrapper::wrap_slice_mut(
&mut [Foreign::default()],
));
let _: &mut [Foreign] =
Wrapper::peel_slice_mut(bytemuck::cast_slice_mut(&mut [u8::default()]));
let _: &[u8] = bytemuck::bytes_of(Wrapper::wrap_ref(&Foreign::default()));
let _: &Foreign = Wrapper::peel_ref(bytemuck::from_bytes(&[u8::default()]));
let _: &mut [u8] =
bytemuck::bytes_of_mut(Wrapper::wrap_mut(&mut Foreign::default()));
let _: &mut Foreign =
Wrapper::peel_mut(bytemuck::from_bytes_mut(&mut [u8::default()]));
// not sure if this is the right usage
let _ =
bytemuck::pod_align_to::<_, u8>(Wrapper::wrap_slice(&[Foreign::default()]));
// counterpart?
// not sure if this is the right usage
let _ = bytemuck::pod_align_to_mut::<_, u8>(Wrapper::wrap_slice_mut(&mut [
Foreign::default(),
]));
// counterpart?
#[cfg(feature = "extern_crate_alloc")]
{
use bytemuck::allocation::TransparentWrapperAlloc;
use std::rc::Rc;
let a: Vec<Foreign> = vec![Foreign::default(); 2];
let b: Vec<Wrapper> = Wrapper::wrap_vec(a);
assert_eq!(b, [0, 0]);
let c: Vec<Foreign> = Wrapper::peel_vec(b);
assert_eq!(c, [0, 0]);
let d: Box<Foreign> = Box::new(Foreign::default());
let e: Box<Wrapper> = Wrapper::wrap_box(d);
assert_eq!(&*e, &0);
let f: Box<Foreign> = Wrapper::peel_box(e);
assert_eq!(&*f, &0);
let g: Rc<Foreign> = Rc::new(Foreign::default());
let h: Rc<Wrapper> = Wrapper::wrap_rc(g);
assert_eq!(&*h, &0);
let i: Rc<Foreign> = Wrapper::peel_rc(h);
assert_eq!(&*i, &0);
#[cfg(target_has_atomic = "ptr")]
{
use std::sync::Arc;
let j: Arc<Foreign> = Arc::new(Foreign::default());
let k: Arc<Wrapper> = Wrapper::wrap_arc(j);
assert_eq!(&*k, &0);
let l: Arc<Foreign> = Wrapper::peel_arc(k);
assert_eq!(&*l, &0);
}
}
}
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