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authorValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
committerValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
commit1b6a04ca5504955c571d1c97504fb45ea0befee4 (patch)
tree7579f518b23313e8a9748a88ab6173d5e030b227 /vendor/bytemuck/tests/doc_tests.rs
parent5ecd8cf2cba827454317368b68571df0d13d7842 (diff)
downloadfparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.tar.xz
fparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.zip
Initial vendor packages
Signed-off-by: Valentin Popov <valentin@popov.link>
Diffstat (limited to 'vendor/bytemuck/tests/doc_tests.rs')
-rw-r--r--vendor/bytemuck/tests/doc_tests.rs123
1 files changed, 123 insertions, 0 deletions
diff --git a/vendor/bytemuck/tests/doc_tests.rs b/vendor/bytemuck/tests/doc_tests.rs
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+#![allow(clippy::disallowed_names)]
+
+//! 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
+ );
+}