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// Original code (./not_unpin.rs):
//
// ```rust
// #![allow(dead_code)]
//
// use pin_project::pin_project;
//
// #[pin_project(!Unpin)]
// pub struct Struct<T, U> {
// #[pin]
// pinned: T,
// unpinned: U,
// }
//
// fn main() {
// fn _is_unpin<T: Unpin>() {}
// // _is_unpin::<Struct<(), ()>>(); //~ ERROR `std::marker::PhantomPinned` cannot be unpinned
// }
// ```
#![allow(dead_code, unused_imports, unused_parens, unknown_lints, renamed_and_removed_lints)]
#![allow(clippy::needless_lifetimes)]
use pin_project::pin_project;
// #[pin_project(!Unpin)]
pub struct Struct<T, U> {
// #[pin]
pinned: T,
unpinned: U,
}
const _: () = {
pub(crate) struct __StructProjection<'pin, T, U>
where
Struct<T, U>: 'pin,
{
pinned: ::pin_project::__private::Pin<&'pin mut (T)>,
unpinned: &'pin mut (U),
}
pub(crate) struct __StructProjectionRef<'pin, T, U>
where
Struct<T, U>: 'pin,
{
pinned: ::pin_project::__private::Pin<&'pin (T)>,
unpinned: &'pin (U),
}
impl<T, U> Struct<T, U> {
pub(crate) fn project<'pin>(
self: ::pin_project::__private::Pin<&'pin mut Self>,
) -> __StructProjection<'pin, T, U> {
unsafe {
let Self { pinned, unpinned } = self.get_unchecked_mut();
__StructProjection {
pinned: ::pin_project::__private::Pin::new_unchecked(pinned),
unpinned,
}
}
}
pub(crate) fn project_ref<'pin>(
self: ::pin_project::__private::Pin<&'pin Self>,
) -> __StructProjectionRef<'pin, T, U> {
unsafe {
let Self { pinned, unpinned } = self.get_ref();
__StructProjectionRef {
pinned: ::pin_project::__private::Pin::new_unchecked(pinned),
unpinned,
}
}
}
}
// Ensure that it's impossible to use pin projections on a #[repr(packed)]
// struct.
//
// See ./struct-default-expanded.rs and https://github.com/taiki-e/pin-project/pull/34
// for details.
#[forbid(unaligned_references, safe_packed_borrows)]
fn __assert_not_repr_packed<T, U>(this: &Struct<T, U>) {
let _ = &this.pinned;
let _ = &this.unpinned;
}
// Create `Unpin` impl that has trivial `Unpin` bounds.
//
// See https://github.com/taiki-e/pin-project/issues/102#issuecomment-540472282
// for details.
impl<'pin, T, U> ::pin_project::__private::Unpin for Struct<T, U> where
::pin_project::__private::Wrapper<'pin, ::pin_project::__private::PhantomPinned>:
::pin_project::__private::Unpin
{
}
// A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
//
// To ensure that users don't accidentally write a non-functional `UnsafeUnpin`
// impls, we emit one ourselves. If the user ends up writing an `UnsafeUnpin`
// impl, they'll get a "conflicting implementations of trait" error when
// coherence checks are run.
#[doc(hidden)]
unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Struct<T, U> where
::pin_project::__private::Wrapper<'pin, ::pin_project::__private::PhantomPinned>:
::pin_project::__private::Unpin
{
}
// Ensure that struct does not implement `Drop`.
//
// See ./struct-default-expanded.rs for details.
trait StructMustNotImplDrop {}
#[allow(clippy::drop_bounds, drop_bounds)]
impl<T: ::pin_project::__private::Drop> StructMustNotImplDrop for T {}
impl<T, U> StructMustNotImplDrop for Struct<T, U> {}
// A dummy impl of `PinnedDrop`, to ensure that users don't accidentally
// write a non-functional `PinnedDrop` impls.
#[doc(hidden)]
impl<T, U> ::pin_project::__private::PinnedDrop for Struct<T, U> {
unsafe fn drop(self: ::pin_project::__private::Pin<&mut Self>) {}
}
};
fn main() {
fn _is_unpin<T: Unpin>() {}
// _is_unpin::<Struct<(), ()>>(); //~ ERROR `std::marker::PhantomPinned` cannot be unpinned
}
|
