Casting ZST to non-ZST will result in a slice length of 0.
Casting non-ZST to ZST will only work if the input slice has length 0, and results in a slice length of 0; if the input slice is not of length 0, PodCastError::OutputSliceWouldHaveSlop is returned.
Updates the docs of the PodCastError variants to reflect when they can occur.
Updates the docs of try_cast_slice (and checked::) to remove note about ZST <-> non-ZST not being allowed.
Update bytes_of(_mut) to remove ZST check, since casting [ZST] -> [u8] is now allowed directly using cast_slice(_mut).
Update must_cast_slice checks and doctests to allow [ZST] -> [non-ZST], but disallow [non-ZST] -> [ZST].
* Fix panics in try_cast_slice_{box,rc,arc},cast_vec.
Casting from non-empty non-ZST slices to ZST slices now returns Err(SizeMismatch) (instead of panicking).
Casting from empty non-ZST slices to ZST slices is allowed and returns an empty slice (instead of panicking).
Casting from ZST slices to non-ZST slices is allowed and returns an empty slice (status quo).
* Add tests for cast_slice_box,rc,arc.
* Change #![allow(clippy::missing_docs_in_private_items)] to #[allow(clippy::missing_docs_in_private_items)], also rustfmt went wild
* fix for 1.34 building.
* clippy be quiet
* derive changelog.
* chore: Release bytemuck_derive version 1.7.0
* Change #![allow(clippy::missing_docs_in_private_items)] to #[allow(clippy::missing_docs_in_private_items)], also rustfmt went wild
* fix for 1.34 building.
* clippy be quiet
Note that the ergonomics are still not great, since `NoUninit` is also required to use `derive(ByteEq, ByteHash)`, and `derive(NoUninit)` doesn't support generics,
but that *explicitly* doesn't support generics, instead of silently ignoring generics like `derive(ByteEq, ByteHash)` used to, so this is strictly an improvement.
* Explicitly document that pod_read_unaligned and try_pod_read_unaligned don't panic on unallowed reads
Their names make that reasonably clear already, but it doesn't hurt to
be explicit. Also, when choosing between `*from_bytes(x)` and
`pod_read_unaligned(x)`, it's good to have a clearly documented
criterion.
* Cosmetic doc changes
Add a couple of missing links, add a missing "like" (consistent with
other similar sentences).
* Remove redundant link
The redundant link emits a warning in `cargo doc`.
* simplify `ToTokens` impl for `Representation`
Instead of collecting the representation and modifier into `Option`s
and determining whether a comma is needed manually, we can use the
`Puncutuated` struct which handles commas automatically.
This will also make emitting the `align` modifier in the future easier.
* emit alignment modifier
This is required for correctly implementing `CheckedBitPattern` because
we need the layout of the type and its `Bits` type to have the same
layout.
* add unit test for `#[repr]` parsing
* allow multiple alignment modifiers
According to RFC #1358, if multiple alignment modifiers are specified,
the resulting alignment is the maximum of all alignment modifiers.
* actually return the error we just created
* factor out the integer Repr's into their own type
This is a preparation step for adding support for `#[repr(C, int)]`.
* allow parsing `#[repr(C, int)]`
This can be used on enums with fields.
* derive `CheckedBitPattern` for enums with fields
The implementation mostly mirrors the desugaring described at
https://doc.rust-lang.org/reference/type-layout.html
* add comments and rename some idents
* update error message
* update docs for `CheckedBitPattern` derive
* add new nested test case, change generated type naming scheme
* fix wrong comment
* small nit
---------
Co-authored-by: Gray Olson <gray@grayolson.com>
