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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 01:47:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 01:47:29 +0000
commit0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch)
treea31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /third_party/rust/pin-project/examples/enum-default-expanded.rs
parentInitial commit. (diff)
downloadfirefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.tar.xz
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Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/pin-project/examples/enum-default-expanded.rs')
-rw-r--r--third_party/rust/pin-project/examples/enum-default-expanded.rs101
1 files changed, 101 insertions, 0 deletions
diff --git a/third_party/rust/pin-project/examples/enum-default-expanded.rs b/third_party/rust/pin-project/examples/enum-default-expanded.rs
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+++ b/third_party/rust/pin-project/examples/enum-default-expanded.rs
@@ -0,0 +1,101 @@
+// Original code (./enum-default.rs):
+//
+// ```rust
+// #![allow(dead_code)]
+//
+// use pin_project::pin_project;
+//
+// #[pin_project(project = EnumProj)]
+// enum Enum<T, U> {
+// Pinned(#[pin] T),
+// Unpinned(U),
+// }
+//
+// fn main() {}
+// ```
+
+#![allow(dead_code, unused_imports, unused_parens, unknown_lints, renamed_and_removed_lints)]
+#![allow(
+ clippy::needless_lifetimes,
+ clippy::just_underscores_and_digits,
+ clippy::used_underscore_binding
+)]
+
+use pin_project::pin_project;
+
+// #[pin_project(project = EnumProj)]
+enum Enum<T, U> {
+ Pinned(/* #[pin] */ T),
+ Unpinned(U),
+}
+
+enum EnumProj<'pin, T, U>
+where
+ Enum<T, U>: 'pin,
+{
+ Pinned(::pin_project::__private::Pin<&'pin mut (T)>),
+ Unpinned(&'pin mut (U)),
+}
+
+const _: () = {
+ // When `#[pin_project]` is used on enums, only named projection types and
+ // methods are generated because there is no way to access variants of
+ // projected types without naming it.
+ // (When `#[pin_project]` is used on structs, both methods are always generated.)
+
+ impl<T, U> Enum<T, U> {
+ fn project<'pin>(
+ self: ::pin_project::__private::Pin<&'pin mut Self>,
+ ) -> EnumProj<'pin, T, U> {
+ unsafe {
+ match self.get_unchecked_mut() {
+ Self::Pinned(_0) => {
+ EnumProj::Pinned(::pin_project::__private::Pin::new_unchecked(_0))
+ }
+ Self::Unpinned(_0) => EnumProj::Unpinned(_0),
+ }
+ }
+ }
+ }
+
+ // Automatically create the appropriate conditional `Unpin` implementation.
+ //
+ // See ./struct-default-expanded.rs and https://github.com/taiki-e/pin-project/pull/53.
+ // for details.
+ struct __Enum<'pin, T, U> {
+ __pin_project_use_generics: ::pin_project::__private::AlwaysUnpin<
+ 'pin,
+ (::pin_project::__private::PhantomData<T>, ::pin_project::__private::PhantomData<U>),
+ >,
+ __field0: T,
+ }
+ impl<'pin, T, U> ::pin_project::__private::Unpin for Enum<T, U> where
+ __Enum<'pin, T, U>: ::pin_project::__private::Unpin
+ {
+ }
+ // A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
+ #[doc(hidden)]
+ unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Enum<T, U> where
+ __Enum<'pin, T, U>: ::pin_project::__private::Unpin
+ {
+ }
+
+ // Ensure that enum does not implement `Drop`.
+ //
+ // See ./struct-default-expanded.rs for details.
+ trait EnumMustNotImplDrop {}
+ #[allow(clippy::drop_bounds, drop_bounds)]
+ impl<T: ::pin_project::__private::Drop> EnumMustNotImplDrop for T {}
+ impl<T, U> EnumMustNotImplDrop for Enum<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 Enum<T, U> {
+ unsafe fn drop(self: ::pin_project::__private::Pin<&mut Self>) {}
+ }
+
+ // We don't need to check for `#[repr(packed)]`,
+ // since it does not apply to enums.
+};
+
+fn main() {}