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|
#![allow(clippy::disallowed_names)]
#![allow(dead_code)]
//! Cargo miri doesn't run doctests yet, so we duplicate these here. It's
//! probably not that important to sweat keeping these perfectly up to date, but
//! we should try to catch the cases where the primary tests are doctests.
use bytemuck::*;
// Miri doesn't run on doctests, so... copypaste to the rescue.
#[test]
fn test_transparent_slice() {
#[repr(transparent)]
struct Slice<T>([T]);
unsafe impl<T> TransparentWrapper<[T]> for Slice<T> {}
let s = Slice::wrap_ref(&[1u32, 2, 3]);
assert_eq!(&s.0, &[1, 2, 3]);
let mut buf = [1, 2, 3u8];
let _sm = Slice::wrap_mut(&mut buf);
}
#[test]
fn test_transparent_basic() {
#[derive(Default)]
struct SomeStruct(u32);
#[repr(transparent)]
struct MyWrapper(SomeStruct);
unsafe impl TransparentWrapper<SomeStruct> for MyWrapper {}
// interpret a reference to &SomeStruct as a &MyWrapper
let thing = SomeStruct::default();
let wrapped_ref: &MyWrapper = MyWrapper::wrap_ref(&thing);
// Works with &mut too.
let mut mut_thing = SomeStruct::default();
let wrapped_mut: &mut MyWrapper = MyWrapper::wrap_mut(&mut mut_thing);
let _ = (wrapped_ref, wrapped_mut);
}
// Work around miri not running doctests
#[test]
fn test_contiguous_doc() {
#[repr(u8)]
#[derive(Debug, Copy, Clone, PartialEq)]
enum Foo {
A = 0,
B = 1,
C = 2,
D = 3,
E = 4,
}
unsafe impl Contiguous for Foo {
type Int = u8;
const MIN_VALUE: u8 = Foo::A as u8;
const MAX_VALUE: u8 = Foo::E as u8;
}
assert_eq!(Foo::from_integer(3).unwrap(), Foo::D);
assert_eq!(Foo::from_integer(8), None);
assert_eq!(Foo::C.into_integer(), 2);
assert_eq!(Foo::B.into_integer(), Foo::B as u8);
}
#[test]
fn test_offsetof_vertex() {
#[repr(C)]
struct Vertex {
pos: [f32; 2],
uv: [u16; 2],
color: [u8; 4],
}
unsafe impl Zeroable for Vertex {}
let pos = offset_of!(Zeroable::zeroed(), Vertex, pos);
let uv = offset_of!(Zeroable::zeroed(), Vertex, uv);
let color = offset_of!(Zeroable::zeroed(), Vertex, color);
assert_eq!(pos, 0);
assert_eq!(uv, 8);
assert_eq!(color, 12);
}
#[test]
fn test_offsetof_nonpod() {
#[derive(Default)]
struct Foo {
a: u8,
b: &'static str,
c: i32,
}
let a_offset = offset_of!(Default::default(), Foo, a);
let b_offset = offset_of!(Default::default(), Foo, b);
let c_offset = offset_of!(Default::default(), Foo, c);
assert_ne!(a_offset, b_offset);
assert_ne!(b_offset, c_offset);
// We can't check against hardcoded values for a repr(Rust) type,
// but prove to ourself this way.
let foo = Foo::default();
// Note: offsets are in bytes.
let as_bytes = &foo as *const _ as *const u8;
// We're using wrapping_offset here because it's not worth
// the unsafe block, but it would be valid to use `add` instead,
// as it cannot overflow.
assert_eq!(
&foo.a as *const _ as usize,
as_bytes.wrapping_add(a_offset) as usize
);
assert_eq!(
&foo.b as *const _ as usize,
as_bytes.wrapping_add(b_offset) as usize
);
assert_eq!(
&foo.c as *const _ as usize,
as_bytes.wrapping_add(c_offset) as usize
);
}
|
