Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 133 insertions, 0 deletions

diff --git a/third_party/rust/pin-project/examples/pinned_drop-expanded.rs b/third_party/rust/pin-project/examples/pinned_drop-expanded.rs
new file mode 100644
index 0000000000..d96dd98e12
--- /dev/null
+++ b/third_party/rust/pin-project/examples/pinned_drop-expanded.rs
@@ -0,0 +1,133 @@
+// Original code (./pinned_drop.rs):
+//
+// ```rust
+// #![allow(dead_code)]
+//
+// use pin_project::{pin_project, pinned_drop};
+// use std::pin::Pin;
+//
+// #[pin_project(PinnedDrop)]
+// pub struct Foo<'a, T> {
+//     was_dropped: &'a mut bool,
+//     #[pin]
+//     field: T,
+// }
+//
+// #[pinned_drop]
+// fn drop_foo<T>(mut this: Pin<&mut Foo<'_, T>>) {
+//     **this.project().was_dropped = true;
+// }
+//
+// fn main() {}
+// ```
+
+#![allow(dead_code, unused_imports, unused_parens)]
+
+use pin_project::{pin_project, pinned_drop};
+use std::pin::Pin;
+
+pub struct Foo<'a, T> {
+    was_dropped: &'a mut bool,
+    // #[pin]
+    field: T,
+}
+
+#[allow(clippy::mut_mut)] // This lint warns `&mut &mut <ty>`.
+#[allow(dead_code)] // This lint warns unused fields/variants.
+pub(crate) struct __FooProjection<'pin, 'a, T> {
+    was_dropped: &'pin mut (&'a mut bool),
+    field: ::core::pin::Pin<&'pin mut (T)>,
+}
+
+#[allow(dead_code)] // This lint warns unused fields/variants.
+pub(crate) struct __FooProjectionRef<'pin, 'a, T> {
+    was_dropped: &'pin (&'a mut bool),
+    field: ::core::pin::Pin<&'pin (T)>,
+}
+
+impl<'a, T> Foo<'a, T> {
+    pub(crate) fn project<'pin>(
+        self: ::core::pin::Pin<&'pin mut Self>,
+    ) -> __FooProjection<'pin, 'a, T> {
+        unsafe {
+            let Foo { was_dropped, field } = self.get_unchecked_mut();
+            __FooProjection { was_dropped, field: ::core::pin::Pin::new_unchecked(field) }
+        }
+    }
+    pub(crate) fn project_ref<'pin>(
+        self: ::core::pin::Pin<&'pin Self>,
+    ) -> __FooProjectionRef<'pin, 'a, T> {
+        unsafe {
+            let Foo { was_dropped, field } = self.get_ref();
+            __FooProjectionRef { was_dropped, field: ::core::pin::Pin::new_unchecked(field) }
+        }
+    }
+}
+
+#[allow(single_use_lifetimes)]
+impl<'a, T> ::core::ops::Drop for Foo<'a, T> {
+    fn drop(&mut self) {
+        // Safety - we're in 'drop', so we know that 'self' will
+        // never move again.
+        let pinned_self = unsafe { ::core::pin::Pin::new_unchecked(self) };
+        // We call `pinned_drop` only once. Since `PinnedDrop::drop`
+        // is an unsafe function and a private API, it is never called again in safe
+        // code *unless the user uses a maliciously crafted macro*.
+        unsafe {
+            ::pin_project::__private::PinnedDrop::drop(pinned_self);
+        }
+    }
+}
+
+// It is safe to implement PinnedDrop::drop, but it is not safe to call it.
+// This is because destructors can be called multiple times (double dropping
+// is unsound: rust-lang/rust#62360).
+//
+// Ideally, it would be desirable to be able to prohibit manual calls in the
+// same way as Drop::drop, but the library cannot. So, by using macros and
+// replacing them with private traits, we prevent users from calling
+// PinnedDrop::drop.
+//
+// Users can implement `Drop` safely using `#[pinned_drop]`.
+// **Do not call or implement this trait directly.**
+impl<T> ::pin_project::__private::PinnedDrop for Foo<'_, T> {
+    // Since calling it twice on the same object would be UB,
+    // this method is unsafe.
+    unsafe fn drop(self: Pin<&mut Self>) {
+        fn __drop_inner<T>(__self: Pin<&mut Foo<'_, T>>) {
+            **__self.project().was_dropped = true;
+        }
+        __drop_inner(self);
+    }
+}
+
+// Automatically create the appropriate conditional `Unpin` implementation.
+//
+// See ./struct-default-expanded.rs and https://github.com/taiki-e/pin-project/pull/53.
+// for details.
+#[allow(non_snake_case)]
+fn __unpin_scope_Foo() {
+    pub struct __Foo<'pin, 'a, T> {
+        __pin_project_use_generics: ::pin_project::__private::AlwaysUnpin<'pin, (T)>,
+        __field0: T,
+        __lifetime0: &'a (),
+    }
+    impl<'pin, 'a, T> ::core::marker::Unpin for Foo<'a, T> where
+        __Foo<'pin, 'a, T>: ::core::marker::Unpin
+    {
+    }
+}
+
+// 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.
+#[allow(single_use_lifetimes)]
+#[allow(non_snake_case)]
+#[deny(safe_packed_borrows)]
+fn __pin_project_assert_not_repr_packed_Foo<'a, T>(val: &Foo<'a, T>) {
+    &val.was_dropped;
+    &val.field;
+}
+
+fn main() {}