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
new file mode 100644
index 0000000000..459ca39b03
--- /dev/null
+++ 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() {}