1 // Original code (./unsafe_unpin.rs):
2 //
3 // ```rust
4 // #![allow(dead_code)]
5 //
6 // use pin_project::{pin_project, UnsafeUnpin};
7 //
8 // #[pin_project(UnsafeUnpin)]
9 // pub struct Struct<T, U> {
10 // #[pin]
11 // pinned: T,
12 // unpinned: U,
13 // }
14 //
15 // unsafe impl<T: Unpin, U> UnsafeUnpin for Struct<T, U> {}
16 //
17 // fn main() {}
18 // ```
19
20 #![allow(dead_code, unused_imports, unused_parens, unknown_lints, renamed_and_removed_lints)]
21 #![allow(clippy::needless_lifetimes)]
22
23 use pin_project::{pin_project, UnsafeUnpin};
24
25 // #[pin_project(UnsafeUnpin)]
26 pub struct Struct<T, U> {
27 // #[pin]
28 pinned: T,
29 unpinned: U,
30 }
31
32 const _: () = {
33 pub(crate) struct __StructProjection<'pin, T, U>
34 where
35 Struct<T, U>: 'pin,
36 {
37 pinned: ::pin_project::__private::Pin<&'pin mut (T)>,
38 unpinned: &'pin mut (U),
39 }
40 pub(crate) struct __StructProjectionRef<'pin, T, U>
41 where
42 Struct<T, U>: 'pin,
43 {
44 pinned: ::pin_project::__private::Pin<&'pin (T)>,
45 unpinned: &'pin (U),
46 }
47
48 impl<T, U> Struct<T, U> {
project<'pin>( self: ::pin_project::__private::Pin<&'pin mut Self>, ) -> __StructProjection<'pin, T, U>49 pub(crate) fn project<'pin>(
50 self: ::pin_project::__private::Pin<&'pin mut Self>,
51 ) -> __StructProjection<'pin, T, U> {
52 unsafe {
53 let Self { pinned, unpinned } = self.get_unchecked_mut();
54 __StructProjection {
55 pinned: ::pin_project::__private::Pin::new_unchecked(pinned),
56 unpinned,
57 }
58 }
59 }
project_ref<'pin>( self: ::pin_project::__private::Pin<&'pin Self>, ) -> __StructProjectionRef<'pin, T, U>60 pub(crate) fn project_ref<'pin>(
61 self: ::pin_project::__private::Pin<&'pin Self>,
62 ) -> __StructProjectionRef<'pin, T, U> {
63 unsafe {
64 let Self { pinned, unpinned } = self.get_ref();
65 __StructProjectionRef {
66 pinned: ::pin_project::__private::Pin::new_unchecked(pinned),
67 unpinned,
68 }
69 }
70 }
71 }
72
73 // Ensure that it's impossible to use pin projections on a #[repr(packed)]
74 // struct.
75 //
76 // See ./struct-default-expanded.rs and https://github.com/taiki-e/pin-project/pull/34
77 // for details.
78 #[forbid(safe_packed_borrows)]
__assert_not_repr_packed<T, U>(this: &Struct<T, U>)79 fn __assert_not_repr_packed<T, U>(this: &Struct<T, U>) {
80 let _ = &this.pinned;
81 let _ = &this.unpinned;
82 }
83
84 // Implement `Unpin` via `UnsafeUnpin`.
85 impl<'pin, T, U> ::pin_project::__private::Unpin for Struct<T, U> where
86 ::pin_project::__private::Wrapper<'pin, Self>: ::pin_project::UnsafeUnpin
87 {
88 }
89
90 // Ensure that struct does not implement `Drop`.
91 //
92 // See ./struct-default-expanded.rs for details.
93 trait StructMustNotImplDrop {}
94 #[allow(clippy::drop_bounds, drop_bounds)]
95 impl<T: ::pin_project::__private::Drop> StructMustNotImplDrop for T {}
96 impl<T, U> StructMustNotImplDrop for Struct<T, U> {}
97 // A dummy impl of `PinnedDrop`, to ensure that users don't accidentally
98 // write a non-functional `PinnedDrop` impls.
99 #[doc(hidden)]
100 impl<T, U> ::pin_project::__private::PinnedDrop for Struct<T, U> {
drop(self: ::pin_project::__private::Pin<&mut Self>)101 unsafe fn drop(self: ::pin_project::__private::Pin<&mut Self>) {}
102 }
103 };
104
105 unsafe impl<T: Unpin, U> UnsafeUnpin for Struct<T, U> {}
106
main()107 fn main() {}
108