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#![allow(clippy::unnecessary_cast)]↩
#![allow(clippy::manual_slice_size_calculation)]↩
↩
use core::mem::size_of;↩
↩
use bytemuck::*;↩
↩
#[test]↩
fn test_try_cast_slice() {↩
// some align4 data↩
let u32_slice: &[u32] = &[4, 5, 6];↩
// the same data as align1↩
let the_bytes: &[u8] = try_cast_slice(u32_slice).unwrap();↩
↩
assert_eq!(↩
u32_slice.as_ptr() as *const u32 as usize,↩
the_bytes.as_ptr() as *const u8 as usize↩
);↩
assert_eq!(↩
u32_slice.len() * size_of::<u32>(),↩
the_bytes.len() * size_of::<u8>()↩
);↩
↩
// by taking one byte off the front, we're definitely mis-aligned for u32.↩
let mis_aligned_bytes = &the_bytes[1..];↩
assert_eq!(↩
try_cast_slice::<u8, u32>(mis_aligned_bytes),↩
Err(PodCastError::TargetAlignmentGreaterAndInputNotAligned)↩
);↩
↩
// by taking one byte off the end, we're aligned but would have slop bytes for↩
// u32↩
let the_bytes_len_minus1 = the_bytes.len() - 1;↩
let slop_bytes = &the_bytes[..the_bytes_len_minus1];↩
assert_eq!(↩
try_cast_slice::<u8, u32>(slop_bytes),↩
Err(PodCastError::OutputSliceWouldHaveSlop)↩
);↩
↩
// if we don't mess with it we can up-alignment cast↩
try_cast_slice::<u8, u32>(the_bytes).unwrap();↩
}↩
↩
#[test]↩
fn test_try_cast_slice_mut() {↩
// some align4 data↩
let u32_slice: &mut [u32] = &mut [4, 5, 6];↩
let u32_len = u32_slice.len();↩
let u32_ptr = u32_slice.as_ptr();↩
↩
// the same data as align1↩
let the_bytes: &mut [u8] = try_cast_slice_mut(u32_slice).unwrap();↩
let the_bytes_len = the_bytes.len();↩
let the_bytes_ptr = the_bytes.as_ptr();↩
↩
assert_eq!(↩
u32_ptr as *const u32 as usize,↩
the_bytes_ptr as *const u8 as usize↩
);↩
assert_eq!(u32_len * size_of::<u32>(), the_bytes_len * size_of::<u8>());↩
↩
// by taking one byte off the front, we're definitely mis-aligned for u32.↩
let mis_aligned_bytes = &mut the_bytes[1..];↩
assert_eq!(↩
try_cast_slice_mut::<u8, u32>(mis_aligned_bytes),↩
Err(PodCastError::TargetAlignmentGreaterAndInputNotAligned)↩
);↩
↩
// by taking one byte off the end, we're aligned but would have slop bytes for↩
// u32↩
let the_bytes_len_minus1 = the_bytes.len() - 1;↩
let slop_bytes = &mut the_bytes[..the_bytes_len_minus1];↩
assert_eq!(↩
try_cast_slice_mut::<u8, u32>(slop_bytes),↩
Err(PodCastError::OutputSliceWouldHaveSlop)↩
);↩
↩
// if we don't mess with it we can up-alignment cast↩
try_cast_slice_mut::<u8, u32>(the_bytes).unwrap();↩
}↩
↩
#[test]↩
fn test_types() {↩
let _: i32 = cast(1.0_f32);↩
let _: &mut i32 = cast_mut(&mut 1.0_f32);↩
let _: &i32 = cast_ref(&1.0_f32);↩
let _: &[i32] = cast_slice(&[1.0_f32]);↩
let _: &mut [i32] = cast_slice_mut(&mut [1.0_f32]);↩
//↩
let _: Result<i32, PodCastError> = try_cast(1.0_f32);↩
let _: Result<&mut i32, PodCastError> = try_cast_mut(&mut 1.0_f32);↩
let _: Result<&i32, PodCastError> = try_cast_ref(&1.0_f32);↩
let _: Result<&[i32], PodCastError> = try_cast_slice(&[1.0_f32]);↩
let _: Result<&mut [i32], PodCastError> = try_cast_slice_mut(&mut [1.0_f32]);↩
}↩
↩
#[test]↩
fn test_bytes_of() {↩
assert_eq!(bytes_of(&0xaabbccdd_u32), &0xaabbccdd_u32.to_ne_bytes());↩
assert_eq!(↩
bytes_of_mut(&mut 0xaabbccdd_u32),↩
&mut 0xaabbccdd_u32.to_ne_bytes()↩
);↩
let mut a = 0xaabbccdd_u32;↩
let a_addr = &a as *const _ as usize;↩
// ensure addresses match.↩
assert_eq!(bytes_of(&a).as_ptr() as usize, a_addr);↩
assert_eq!(bytes_of_mut(&mut a).as_ptr() as usize, a_addr);↩
}↩
↩
#[test]↩
fn test_try_from_bytes() {↩
let u32s = [0xaabbccdd, 0x11223344_u32];↩
let bytes = bytemuck::cast_slice::<u32, u8>(&u32s);↩
assert_eq!(try_from_bytes::<u32>(&bytes[..4]), Ok(&u32s[0]));↩
assert_eq!(↩
try_from_bytes::<u32>(&bytes[..5]),↩
Err(PodCastError::SizeMismatch)↩
);↩
assert_eq!(↩
try_from_bytes::<u32>(&bytes[..3]),↩
Err(PodCastError::SizeMismatch)↩
);↩
assert_eq!(↩
try_from_bytes::<u32>(&bytes[1..5]),↩
Err(PodCastError::TargetAlignmentGreaterAndInputNotAligned)↩
);↩
}↩
↩
#[test]↩
fn test_try_from_bytes_mut() {↩
let mut abcd = 0xaabbccdd;↩
let mut u32s = [abcd, 0x11223344_u32];↩
let bytes = bytemuck::cast_slice_mut::<u32, u8>(&mut u32s);↩
assert_eq!(try_from_bytes_mut::<u32>(&mut bytes[..4]), Ok(&mut abcd));↩
assert_eq!(try_from_bytes_mut::<u32>(&mut bytes[..4]), Ok(&mut abcd));↩
assert_eq!(↩
try_from_bytes_mut::<u32>(&mut bytes[..5]),↩
Err(PodCastError::SizeMismatch)↩
);↩
assert_eq!(↩
try_from_bytes_mut::<u32>(&mut bytes[..3]),↩
Err(PodCastError::SizeMismatch)↩
);↩
assert_eq!(↩
try_from_bytes::<u32>(&bytes[1..5]),↩
Err(PodCastError::TargetAlignmentGreaterAndInputNotAligned)↩
);↩
}↩
↩
#[test]↩
fn test_from_bytes() {↩
let abcd = 0xaabbccdd_u32;↩
let aligned_bytes = bytemuck::bytes_of(&abcd);↩
assert_eq!(from_bytes::<u32>(aligned_bytes), &abcd);↩
assert!(core::ptr::eq(from_bytes(aligned_bytes), &abcd));↩
}↩
↩
#[test]↩
fn test_from_bytes_mut() {↩
let mut a = 0xaabbccdd_u32;↩
let a_addr = &a as *const _ as usize;↩
let aligned_bytes = bytemuck::bytes_of_mut(&mut a);↩
assert_eq!(*from_bytes_mut::<u32>(aligned_bytes), 0xaabbccdd_u32);↩
assert_eq!(↩
from_bytes_mut::<u32>(aligned_bytes) as *const u32 as usize,↩
a_addr↩
);↩
}↩
↩
// like #[should_panic], but can be a part of another test, instead of requiring↩
// it to be it's own test.↩
macro_rules! should_panic {↩
($ex:expr) => {↩
assert!(↩
std::panic::catch_unwind(|| {↩
let _ = $ex;↩
})↩
.is_err(),↩
concat!("should have panicked: `", stringify!($ex), "`")↩
);↩
};↩
}↩
↩
#[test]↩
fn test_panics() {↩
should_panic!(cast_slice::<u8, u32>(&[1u8, 2u8]));↩
should_panic!(cast_slice_mut::<u8, u32>(&mut [1u8, 2u8]));↩
should_panic!(from_bytes::<u32>(&[1u8, 2]));↩
should_panic!(from_bytes::<u32>(&[1u8, 2, 3, 4, 5]));↩
should_panic!(from_bytes_mut::<u32>(&mut [1u8, 2]));↩
should_panic!(from_bytes_mut::<u32>(&mut [1u8, 2, 3, 4, 5]));↩
// use cast_slice on some u32s to get some align>=4 bytes, so we can know↩
// we'll give from_bytes unaligned ones.↩
let aligned_bytes = bytemuck::cast_slice::<u32, u8>(&[0, 0]);↩
should_panic!(from_bytes::<u32>(&aligned_bytes[1..5]));↩
}↩
↩
#[test]↩
fn test_zsts() {↩
#[derive(Debug, Clone, Copy)]↩
struct MyZst;↩
unsafe impl Zeroable for MyZst {}↩
unsafe impl Pod for MyZst {}↩
assert_eq!(42, cast_slice::<(), MyZst>(&[(); 42]).len());↩
assert_eq!(42, cast_slice_mut::<(), MyZst>(&mut [(); 42]).len());↩
assert_eq!(0, cast_slice::<(), u8>(&[(); 42]).len());↩
assert_eq!(0, cast_slice_mut::<(), u8>(&mut [(); 42]).len());↩
assert_eq!(0, cast_slice::<u8, ()>(&[]).len());↩
assert_eq!(0, cast_slice_mut::<u8, ()>(&mut []).len());↩
↩
assert_eq!(↩
PodCastError::OutputSliceWouldHaveSlop,↩
try_cast_slice::<u8, ()>(&[42]).unwrap_err()↩
);↩
↩
assert_eq!(↩
PodCastError::OutputSliceWouldHaveSlop,↩
try_cast_slice_mut::<u8, ()>(&mut [42]).unwrap_err()↩
);↩
}↩
↩
#[cfg(feature = "extern_crate_alloc")]↩
#[test]↩
fn test_boxed_slices() {↩
let boxed_u8_slice: Box<[u8]> = Box::new([0, 1, u8::MAX, i8::MAX as u8]);↩
let boxed_i8_slice: Box<[i8]> = cast_slice_box::<u8, i8>(boxed_u8_slice);↩
assert_eq!(&*boxed_i8_slice, [0, 1, -1, i8::MAX]);↩
↩
let result: Result<Box<[u16]>, (PodCastError, Box<[i8]>)> =↩
try_cast_slice_box(boxed_i8_slice);↩
let (error, boxed_i8_slice) =↩
result.expect_err("u16 and i8 have different alignment");↩
assert_eq!(error, PodCastError::AlignmentMismatch);↩
↩
let result: Result<&[[i8; 3]], PodCastError> =↩
try_cast_slice(&*boxed_i8_slice);↩
let error =↩
result.expect_err("slice of [i8; 3] cannot be made from slice of 4 i8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
let result: Result<Box<[[i8; 3]]>, (PodCastError, Box<[i8]>)> =↩
try_cast_slice_box(boxed_i8_slice);↩
let (error, boxed_i8_slice) =↩
result.expect_err("slice of [i8; 3] cannot be made from slice of 4 i8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
let empty: Box<[()]> = cast_slice_box::<u8, ()>(Box::new([]));↩
assert!(empty.is_empty());↩
↩
let result: Result<Box<[()]>, (PodCastError, Box<[i8]>)> =↩
try_cast_slice_box(boxed_i8_slice);↩
let (error, boxed_i8_slice) =↩
result.expect_err("slice of ZST cannot be made from slice of 4 u8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
drop(boxed_i8_slice);↩
↩
let empty: Box<[i8]> = cast_slice_box::<(), i8>(Box::new([]));↩
assert!(empty.is_empty());↩
↩
let empty: Box<[i8]> = cast_slice_box::<(), i8>(Box::new([(); 42]));↩
assert!(empty.is_empty());↩
}↩
↩
#[cfg(feature = "extern_crate_alloc")]↩
#[test]↩
fn test_rc_slices() {↩
use std::rc::Rc;↩
let rc_u8_slice: Rc<[u8]> = Rc::new([0, 1, u8::MAX, i8::MAX as u8]);↩
let rc_i8_slice: Rc<[i8]> = cast_slice_rc::<u8, i8>(rc_u8_slice);↩
assert_eq!(&*rc_i8_slice, [0, 1, -1, i8::MAX]);↩
↩
let result: Result<Rc<[u16]>, (PodCastError, Rc<[i8]>)> =↩
try_cast_slice_rc(rc_i8_slice);↩
let (error, rc_i8_slice) =↩
result.expect_err("u16 and i8 have different alignment");↩
assert_eq!(error, PodCastError::AlignmentMismatch);↩
↩
let result: Result<&[[i8; 3]], PodCastError> = try_cast_slice(&*rc_i8_slice);↩
let error =↩
result.expect_err("slice of [i8; 3] cannot be made from slice of 4 i8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
let result: Result<Rc<[[i8; 3]]>, (PodCastError, Rc<[i8]>)> =↩
try_cast_slice_rc(rc_i8_slice);↩
let (error, rc_i8_slice) =↩
result.expect_err("slice of [i8; 3] cannot be made from slice of 4 i8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
let empty: Rc<[()]> = cast_slice_rc::<u8, ()>(Rc::new([]));↩
assert!(empty.is_empty());↩
↩
let result: Result<Rc<[()]>, (PodCastError, Rc<[i8]>)> =↩
try_cast_slice_rc(rc_i8_slice);↩
let (error, rc_i8_slice) =↩
result.expect_err("slice of ZST cannot be made from slice of 4 u8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
drop(rc_i8_slice);↩
↩
let empty: Rc<[i8]> = cast_slice_rc::<(), i8>(Rc::new([]));↩
assert!(empty.is_empty());↩
↩
let empty: Rc<[i8]> = cast_slice_rc::<(), i8>(Rc::new([(); 42]));↩
assert!(empty.is_empty());↩
}↩
↩
#[cfg(feature = "extern_crate_alloc")]↩
#[cfg(target_has_atomic = "ptr")]↩
#[test]↩
fn test_arc_slices() {↩
use std::sync::Arc;↩
let arc_u8_slice: Arc<[u8]> = Arc::new([0, 1, u8::MAX, i8::MAX as u8]);↩
let arc_i8_slice: Arc<[i8]> = cast_slice_arc::<u8, i8>(arc_u8_slice);↩
assert_eq!(&*arc_i8_slice, [0, 1, -1, i8::MAX]);↩
↩
let result: Result<Arc<[u16]>, (PodCastError, Arc<[i8]>)> =↩
try_cast_slice_arc(arc_i8_slice);↩
let (error, arc_i8_slice) =↩
result.expect_err("u16 and i8 have different alignment");↩
assert_eq!(error, PodCastError::AlignmentMismatch);↩
↩
let result: Result<&[[i8; 3]], PodCastError> = try_cast_slice(&*arc_i8_slice);↩
let error =↩
result.expect_err("slice of [i8; 3] cannot be made from slice of 4 i8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
let result: Result<Arc<[[i8; 3]]>, (PodCastError, Arc<[i8]>)> =↩
try_cast_slice_arc(arc_i8_slice);↩
let (error, arc_i8_slice) =↩
result.expect_err("slice of [i8; 3] cannot be made from slice of 4 i8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
let empty: Arc<[()]> = cast_slice_arc::<u8, ()>(Arc::new([]));↩
assert!(empty.is_empty());↩
↩
let result: Result<Arc<[()]>, (PodCastError, Arc<[i8]>)> =↩
try_cast_slice_arc(arc_i8_slice);↩
let (error, arc_i8_slice) =↩
result.expect_err("slice of ZST cannot be made from slice of 4 u8s");↩
assert_eq!(error, PodCastError::OutputSliceWouldHaveSlop);↩
↩
drop(arc_i8_slice);↩
↩
let empty: Arc<[i8]> = cast_slice_arc::<(), i8>(Arc::new([]));↩
assert!(empty.is_empty());↩
↩
let empty: Arc<[i8]> = cast_slice_arc::<(), i8>(Arc::new([(); 42]));↩
assert!(empty.is_empty());↩
}↩
↩
#[cfg(feature = "extern_crate_alloc")]↩
#[test]↩
fn box_bytes_zst() {↩
let x: BoxBytes = box_bytes_of(Box::new([0u8; 0]));↩
let _: Box<[u8]> = from_box_bytes(x);↩
↩
let x: BoxBytes = box_bytes_of(Box::new([0u8; 0]));↩
let _: Box<[()]> = from_box_bytes(x);↩
↩
let x: BoxBytes = box_bytes_of(Box::new([(); 0]));↩
let _: Box<[u8]> = from_box_bytes(x);↩
↩
let x: BoxBytes = box_bytes_of(Box::new([0u8]));↩
let res: Result<Box<[()]>, _> = try_from_box_bytes(x);↩
assert_eq!(res.unwrap_err().0, PodCastError::OutputSliceWouldHaveSlop);↩
↩
// regression test for dropping zero-sized BoxBytes↩
let _: BoxBytes = box_bytes_of(Box::new([0u8; 0]));↩
}↩