102 lines
3.1 KiB
Rust
102 lines
3.1 KiB
Rust
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// Original code (./enum-default.rs):
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//
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// ```rust
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// #![allow(dead_code)]
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//
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// use pin_project::pin_project;
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//
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// #[pin_project(project = EnumProj)]
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// enum Enum<T, U> {
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// Pinned(#[pin] T),
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// Unpinned(U),
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// }
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//
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// fn main() {}
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// ```
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#![allow(dead_code, unused_imports, unused_parens, unknown_lints, renamed_and_removed_lints)]
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#![allow(
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clippy::needless_lifetimes,
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clippy::just_underscores_and_digits,
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clippy::used_underscore_binding
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)]
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use pin_project::pin_project;
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// #[pin_project(project = EnumProj)]
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enum Enum<T, U> {
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Pinned(/* #[pin] */ T),
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Unpinned(U),
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}
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enum EnumProj<'pin, T, U>
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where
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Enum<T, U>: 'pin,
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{
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Pinned(::pin_project::__private::Pin<&'pin mut (T)>),
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Unpinned(&'pin mut (U)),
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}
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const _: () = {
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// When `#[pin_project]` is used on enums, only named projection types and
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// methods are generated because there is no way to access variants of
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// projected types without naming it.
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// (When `#[pin_project]` is used on structs, both methods are always generated.)
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impl<T, U> Enum<T, U> {
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fn project<'pin>(
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self: ::pin_project::__private::Pin<&'pin mut Self>,
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) -> EnumProj<'pin, T, U> {
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unsafe {
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match self.get_unchecked_mut() {
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Self::Pinned(_0) => {
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EnumProj::Pinned(::pin_project::__private::Pin::new_unchecked(_0))
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}
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Self::Unpinned(_0) => EnumProj::Unpinned(_0),
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}
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}
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}
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}
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// Automatically create the appropriate conditional `Unpin` implementation.
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//
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// See ./struct-default-expanded.rs and https://github.com/taiki-e/pin-project/pull/53.
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// for details.
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struct __Enum<'pin, T, U> {
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__pin_project_use_generics: ::pin_project::__private::AlwaysUnpin<
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'pin,
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(::pin_project::__private::PhantomData<T>, ::pin_project::__private::PhantomData<U>),
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>,
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__field0: T,
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}
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impl<'pin, T, U> ::pin_project::__private::Unpin for Enum<T, U> where
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__Enum<'pin, T, U>: ::pin_project::__private::Unpin
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{
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}
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// A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
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#[doc(hidden)]
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unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Enum<T, U> where
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__Enum<'pin, T, U>: ::pin_project::__private::Unpin
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{
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}
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// Ensure that enum does not implement `Drop`.
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//
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// See ./struct-default-expanded.rs for details.
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trait EnumMustNotImplDrop {}
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#[allow(clippy::drop_bounds, drop_bounds)]
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impl<T: ::pin_project::__private::Drop> EnumMustNotImplDrop for T {}
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impl<T, U> EnumMustNotImplDrop for Enum<T, U> {}
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// A dummy impl of `PinnedDrop`, to ensure that users don't accidentally
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// write a non-functional `PinnedDrop` impls.
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#[doc(hidden)]
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impl<T, U> ::pin_project::__private::PinnedDrop for Enum<T, U> {
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unsafe fn drop(self: ::pin_project::__private::Pin<&mut Self>) {}
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}
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// We don't need to check for `#[repr(packed)]`,
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// since it does not apply to enums.
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};
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fn main() {}
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