Use pin-weak from crates.io

Cargo.toml

@@ -23,7 +23,6 @@ members = [
     'helper_crates/const-field-offset',
     'helper_crates/vtable',
     'helper_crates/vtable/macro',
-    'helper_crates/pin-weak',
     'xtask',
     'tests/driver',
     'tests/driver_lib',

api/sixtyfps-rs/Cargo.toml

@@ -12,7 +12,7 @@ once_cell = "1.4"
 sixtyfps-rs-macro= { path = "sixtyfps-rs-macro" }
 const-field-offset = { path = "../../helper_crates/const-field-offset" }
 vtable = { path = "../../helper_crates/vtable" }
-pin-weak = { path = "../../helper_crates/pin-weak" }
+pin-weak = "1"
 sixtyfps_corelib = { path="../../sixtyfps_runtime/corelib" }
 # FIXME: should be under a feature or somehow done differently
 sixtyfps_rendering_backend_gl = { path="../../sixtyfps_runtime/rendering_backends/gl" }

helper_crates/pin-weak/Cargo.toml

@@ -1,9 +0,0 @@
-[package]
-name = "pin-weak"
-version = "0.1.0"
-authors = ["Olivier Goffart <ogoffart@sixtyfps.io>"]
-edition = "2018"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]

helper_crates/pin-weak/src/lib.rs

@@ -1,141 +0,0 @@
-/*!
-This create provides weak pointers for `Pin<std::rc::Rc<T>>` and  `Pin<std::rc::Arc<T>>`
-
-## Motivation
-
-`Pin<std::rc::Rc<T>>` and `Pin<std::rc::Arc<T>>` cannot be converted safely to
-their `Weak<T>` equivalent if `T` does not implement `Unpin`.
-That's because it would otherwise be possible to do something like this:
-
-```
-# use std::{pin::Pin, marker::PhantomPinned, rc::{Rc, Weak}};
-struct SomeStruct(PhantomPinned);
-let pinned = Rc::pin(SomeStruct(PhantomPinned));
-
-// This is unsafe ...
-let weak = unsafe {
-    Rc::downgrade(&Pin::into_inner_unchecked(pinned.clone()))
-};
-
-// ... because otherwise it would be possible to move the content of pinned:
-let mut unpinned_rc = weak.upgrade().unwrap();
-std::mem::drop((pinned, weak));
-// unpinned_rc is now the only reference so this will work:
-let x = std::mem::replace(
-    Rc::get_mut(&mut unpinned_rc).unwrap(),
-    SomeStruct(PhantomPinned),
-);
-```
-
-In that example, `x` is the original `SomeStruct` which we moved in memory,
-**that is undefined behavior**, do not do that at home.
-
-## `PinWeak`
-
-This crate simply provide a `rc::PinWeak` and `sync::PinWeak` which allow to
-get weak pointer from `Pin<std::rc::Rc>` and `Pin<srd::sync::Arc>`.
-
-This is safe because you can one can only get back a `Pin` out of it when
-trying to upgrade the weak pointer.
-
-`PinWeak` can be created using the `PinWeak` downgrade function.
-
-## Example
-
-```
-use pin_weak::rc::*;
-# use std::marker::PhantomPinned;
-struct SomeStruct(PhantomPinned, usize);
-let pinned = Rc::pin(SomeStruct(PhantomPinned, 42));
-let weak = PinWeak::downgrade(pinned.clone());
-assert_eq!(weak.upgrade().unwrap().1, 42);
-std::mem::drop(pinned);
-assert!(weak.upgrade().is_none());
-```
-
-*/
-
-#![no_std]
-extern crate alloc;
-
-/// The implementation is in a macro because it is repeated for Arc and Rc
-macro_rules! implementation {
-    ($Rc:ident, $Weak:ident, $rc_lit:literal) => {
-        #[doc(no_inline)]
-        /// re-exported for convinience
-        pub use core::pin::Pin;
-        /// This is a safe wrapper around something that could be compared to `Pin<Weak<T>>`
-        ///
-        /// The typical way to obtain a `PinWeak` is to call `PinWeak::downgrade`
-        #[derive(Debug)]
-        pub struct PinWeak<T: ?Sized>(Weak<T>);
-        impl<T> Default for PinWeak<T> {
-            fn default() -> Self { Self(Weak::default()) }
-        }
-        impl<T: ?Sized> Clone for PinWeak<T> {
-            fn clone(&self) -> Self { Self(self.0.clone()) }
-        }
-        impl<T: ?Sized> PinWeak<T> {
-            /// Equivalent function to `
-            #[doc = $rc_lit]
-            /// ::downgrade`,  but taking a `Pin<
-            #[doc = $rc_lit]
-            /// <T>>` instead.
-            pub fn downgrade(rc: Pin<$Rc<T>>) -> Self {
-                // Safety: we will never return anythning else than a Pin<Rc>
-                unsafe { Self($Rc::downgrade(&Pin::into_inner_unchecked(rc))) }
-            }
-            /// Equivalent function to `Weak::upgrade` but returning a `Pin<
-            #[doc = $rc_lit]
-            /// <T>>` instead.
-            pub fn upgrade(&self) -> Option<Pin<$Rc<T>>> {
-                // Safety: the weak was contructed from a Pin<Rc<T>>
-                self.0.upgrade().map(|rc| unsafe { Pin::new_unchecked(rc) })
-            }
-        }
-
-        #[test]
-        fn test() {
-            struct Foo {
-                _p: core::marker::PhantomPinned,
-                u: u32,
-            }
-            impl Foo {
-                fn new(u: u32) -> Self {
-                    Self { _p: core::marker::PhantomPinned, u }
-                }
-            }
-            let c = $Rc::pin(Foo::new(44));
-            let weak1 = PinWeak::downgrade(c.clone());
-            assert_eq!(weak1.upgrade().unwrap().u, 44);
-            assert_eq!(weak1.clone().upgrade().unwrap().u, 44);
-            let weak2 = PinWeak::downgrade(c.clone());
-            assert_eq!(weak2.upgrade().unwrap().u, 44);
-            assert_eq!(weak1.upgrade().unwrap().u, 44);
-            // note that this moves c and therefore it will be dropped
-            let weak3 = PinWeak::downgrade(c);
-            assert!(weak3.upgrade().is_none());
-            assert!(weak2.upgrade().is_none());
-            assert!(weak1.upgrade().is_none());
-            assert!(weak1.clone().upgrade().is_none());
-
-            let def = PinWeak::<alloc::boxed::Box<&'static mut ()>>::default();
-            assert!(def.upgrade().is_none());
-            assert!(def.clone().upgrade().is_none());
-        }
-    };
-}
-
-pub mod rc {
-    #[doc(no_inline)]
-    /// re-exported for convinience
-    pub use alloc::rc::{Rc, Weak};
-    implementation! {Rc, Weak, "Rc"}
-}
-
-pub mod sync {
-    #[doc(no_inline)]
-    /// re-exported for convinience
-    pub use alloc::sync::{Arc, Weak};
-    implementation! {Arc, Weak, "Arc"}
-}

sixtyfps_runtime/corelib/Cargo.toml

@@ -41,4 +41,4 @@ pathfinder_geometry = "0.5.1"
 cbindgen = "0.14.2"
 
 [dev-dependencies]
-pin-weak = { path = "../../helper_crates/pin-weak" }
+pin-weak = "1"