| // 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 |
| } |