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-rw-r--r--third_party/rust/owning_ref/.cargo-checksum.json1
-rw-r--r--third_party/rust/owning_ref/CHANGELOG.md8
-rw-r--r--third_party/rust/owning_ref/Cargo.toml24
-rw-r--r--third_party/rust/owning_ref/LICENSE21
-rw-r--r--third_party/rust/owning_ref/README.md64
-rw-r--r--third_party/rust/owning_ref/src/lib.rs2016
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diff --git a/third_party/rust/owning_ref/.cargo-checksum.json b/third_party/rust/owning_ref/.cargo-checksum.json
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@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"9a3880e4d5435ca03c0197c45d4ce6b6db6d3fb7eda855f297bafc2ec28af836","Cargo.toml":"91184e6b143ddf621fe7e6757fb28d8eb4c0e01f541fbd0dc440bf076ebfd20d","LICENSE":"90bc15ed094593083fd129fdd1a03607be80fe8839c5564616a5961ab7f7a194","README.md":"0dfea39ad1662ed0a61bb1453eafc207a53dfe577e7846c87d3a5161574fdb12","src/lib.rs":"2e423e210bf2e3ee5e4c426b9a3c9b7756fc434beff1ccf9afa48704e4ac993d"},"package":"6ff55baddef9e4ad00f88b6c743a2a8062d4c6ade126c2a528644b8e444d52ce"} \ No newline at end of file
diff --git a/third_party/rust/owning_ref/CHANGELOG.md b/third_party/rust/owning_ref/CHANGELOG.md
new file mode 100644
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--- /dev/null
+++ b/third_party/rust/owning_ref/CHANGELOG.md
@@ -0,0 +1,8 @@
+# Changelog
+
+## [0.4.1] - 2020-02-27
+### Added
+- `map_with_owner` (#51)
+
+### Changed
+- Use dyn for trait objects (#53)
diff --git a/third_party/rust/owning_ref/Cargo.toml b/third_party/rust/owning_ref/Cargo.toml
new file mode 100644
index 0000000000..057fd5c1bb
--- /dev/null
+++ b/third_party/rust/owning_ref/Cargo.toml
@@ -0,0 +1,24 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+name = "owning_ref"
+version = "0.4.1"
+authors = ["Marvin Löbel <loebel.marvin@gmail.com>"]
+description = "A library for creating references that carry their owner with them."
+documentation = "http://kimundi.github.io/owning-ref-rs/owning_ref/index.html"
+readme = "README.md"
+keywords = ["reference", "sibling", "field", "owning"]
+license = "MIT"
+repository = "https://github.com/Kimundi/owning-ref-rs"
+[dependencies.stable_deref_trait]
+version = "1.0.0"
diff --git a/third_party/rust/owning_ref/LICENSE b/third_party/rust/owning_ref/LICENSE
new file mode 100644
index 0000000000..dff72d1e43
--- /dev/null
+++ b/third_party/rust/owning_ref/LICENSE
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Marvin Löbel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/third_party/rust/owning_ref/README.md b/third_party/rust/owning_ref/README.md
new file mode 100644
index 0000000000..ad32ac24fd
--- /dev/null
+++ b/third_party/rust/owning_ref/README.md
@@ -0,0 +1,64 @@
+[![Build Status](https://travis-ci.org/Kimundi/owning-ref-rs.svg)](https://travis-ci.org/Kimundi/owning-ref-rs)
+[![Crate](https://img.shields.io/crates/v/owning_ref.svg)](https://crates.io/crates/owning_ref)
+[![Docs](https://docs.rs/owning_ref/badge.svg)](https://docs.rs/owning_ref)
+
+owning-ref-rs
+==============
+
+A library for creating references that carry their owner with them.
+
+This can sometimes be useful because Rust borrowing rules normally prevent
+moving a type that has been borrowed from. For example, this kind of code gets rejected:
+
+```rust
+fn return_owned_and_referenced<'a>() -> (Vec<u8>, &'a [u8]) {
+ let v = vec![1, 2, 3, 4];
+ let s = &v[1..3];
+ (v, s)
+}
+```
+
+This library enables this safe usage by keeping the owner and the reference
+bundled together in a wrapper type that ensure that lifetime constraint:
+
+```rust
+fn return_owned_and_referenced() -> OwningRef<Vec<u8>, [u8]> {
+ let v = vec![1, 2, 3, 4];
+ let or = OwningRef::new(v);
+ let or = or.map(|v| &v[1..3]);
+ or
+}
+```
+
+## Getting Started
+
+To get started, add the following to `Cargo.toml`.
+
+```toml
+owning_ref = "0.4.1"
+```
+
+...and see the [docs](http://kimundi.github.io/owning-ref-rs/owning_ref/index.html) for how to use it.
+
+
+## Example
+
+```rust
+extern crate owning_ref;
+use owning_ref::BoxRef;
+
+fn main() {
+ // Create an array owned by a Box.
+ let arr = Box::new([1, 2, 3, 4]) as Box<[i32]>;
+
+ // Transfer into a BoxRef.
+ let arr: BoxRef<[i32]> = BoxRef::new(arr);
+ assert_eq!(&*arr, &[1, 2, 3, 4]);
+
+ // We can slice the array without losing ownership or changing type.
+ let arr: BoxRef<[i32]> = arr.map(|arr| &arr[1..3]);
+ assert_eq!(&*arr, &[2, 3]);
+
+ // Also works for Arc, Rc, String and Vec!
+}
+```
diff --git a/third_party/rust/owning_ref/src/lib.rs b/third_party/rust/owning_ref/src/lib.rs
new file mode 100644
index 0000000000..fa2f15a220
--- /dev/null
+++ b/third_party/rust/owning_ref/src/lib.rs
@@ -0,0 +1,2016 @@
+#![warn(missing_docs)]
+
+/*!
+# An owning reference.
+
+This crate provides the _owning reference_ types `OwningRef` and `OwningRefMut`
+that enables it to bundle a reference together with the owner of the data it points to.
+This allows moving and dropping of a `OwningRef` without needing to recreate the reference.
+
+This can sometimes be useful because Rust borrowing rules normally prevent
+moving a type that has been moved from. For example, this kind of code gets rejected:
+
+```rust,ignore
+fn return_owned_and_referenced<'a>() -> (Vec<u8>, &'a [u8]) {
+ let v = vec![1, 2, 3, 4];
+ let s = &v[1..3];
+ (v, s)
+}
+```
+
+Even though, from a memory-layout point of view, this can be entirely safe
+if the new location of the vector still lives longer than the lifetime `'a`
+of the reference because the backing allocation of the vector does not change.
+
+This library enables this safe usage by keeping the owner and the reference
+bundled together in a wrapper type that ensure that lifetime constraint:
+
+```rust
+# extern crate owning_ref;
+# use owning_ref::OwningRef;
+# fn main() {
+fn return_owned_and_referenced() -> OwningRef<Vec<u8>, [u8]> {
+ let v = vec![1, 2, 3, 4];
+ let or = OwningRef::new(v);
+ let or = or.map(|v| &v[1..3]);
+ or
+}
+# }
+```
+
+It works by requiring owner types to dereference to stable memory locations
+and preventing mutable access to root containers, which in practice requires heap allocation
+as provided by `Box<T>`, `Rc<T>`, etc.
+
+Also provided are typedefs for common owner type combinations,
+which allow for less verbose type signatures. For example, `BoxRef<T>` instead of `OwningRef<Box<T>, T>`.
+
+The crate also provides the more advanced `OwningHandle` type,
+which allows more freedom in bundling a dependent handle object
+along with the data it depends on, at the cost of some unsafe needed in the API.
+See the documentation around `OwningHandle` for more details.
+
+# Examples
+
+## Basics
+
+```
+extern crate owning_ref;
+use owning_ref::BoxRef;
+
+fn main() {
+ // Create an array owned by a Box.
+ let arr = Box::new([1, 2, 3, 4]) as Box<[i32]>;
+
+ // Transfer into a BoxRef.
+ let arr: BoxRef<[i32]> = BoxRef::new(arr);
+ assert_eq!(&*arr, &[1, 2, 3, 4]);
+
+ // We can slice the array without losing ownership or changing type.
+ let arr: BoxRef<[i32]> = arr.map(|arr| &arr[1..3]);
+ assert_eq!(&*arr, &[2, 3]);
+
+ // Also works for Arc, Rc, String and Vec!
+}
+```
+
+## Caching a reference to a struct field
+
+```
+extern crate owning_ref;
+use owning_ref::BoxRef;
+
+fn main() {
+ struct Foo {
+ tag: u32,
+ x: u16,
+ y: u16,
+ z: u16,
+ }
+ let foo = Foo { tag: 1, x: 100, y: 200, z: 300 };
+
+ let or = BoxRef::new(Box::new(foo)).map(|foo| {
+ match foo.tag {
+ 0 => &foo.x,
+ 1 => &foo.y,
+ 2 => &foo.z,
+ _ => panic!(),
+ }
+ });
+
+ assert_eq!(*or, 200);
+}
+```
+
+## Caching a reference to an entry in a vector
+
+```
+extern crate owning_ref;
+use owning_ref::VecRef;
+
+fn main() {
+ let v = VecRef::new(vec![1, 2, 3, 4, 5]).map(|v| &v[3]);
+ assert_eq!(*v, 4);
+}
+```
+
+## Caching a subslice of a String
+
+```
+extern crate owning_ref;
+use owning_ref::StringRef;
+
+fn main() {
+ let s = StringRef::new("hello world".to_owned())
+ .map(|s| s.split(' ').nth(1).unwrap());
+
+ assert_eq!(&*s, "world");
+}
+```
+
+## Reference counted slices that share ownership of the backing storage
+
+```
+extern crate owning_ref;
+use owning_ref::RcRef;
+use std::rc::Rc;
+
+fn main() {
+ let rc: RcRef<[i32]> = RcRef::new(Rc::new([1, 2, 3, 4]) as Rc<[i32]>);
+ assert_eq!(&*rc, &[1, 2, 3, 4]);
+
+ let rc_a: RcRef<[i32]> = rc.clone().map(|s| &s[0..2]);
+ let rc_b = rc.clone().map(|s| &s[1..3]);
+ let rc_c = rc.clone().map(|s| &s[2..4]);
+ assert_eq!(&*rc_a, &[1, 2]);
+ assert_eq!(&*rc_b, &[2, 3]);
+ assert_eq!(&*rc_c, &[3, 4]);
+
+ let rc_c_a = rc_c.clone().map(|s| &s[1]);
+ assert_eq!(&*rc_c_a, &4);
+}
+```
+
+## Atomic reference counted slices that share ownership of the backing storage
+
+```
+extern crate owning_ref;
+use owning_ref::ArcRef;
+use std::sync::Arc;
+
+fn main() {
+ use std::thread;
+
+ fn par_sum(rc: ArcRef<[i32]>) -> i32 {
+ if rc.len() == 0 {
+ return 0;
+ } else if rc.len() == 1 {
+ return rc[0];
+ }
+ let mid = rc.len() / 2;
+ let left = rc.clone().map(|s| &s[..mid]);
+ let right = rc.map(|s| &s[mid..]);
+
+ let left = thread::spawn(move || par_sum(left));
+ let right = thread::spawn(move || par_sum(right));
+
+ left.join().unwrap() + right.join().unwrap()
+ }
+
+ let rc: Arc<[i32]> = Arc::new([1, 2, 3, 4]);
+ let rc: ArcRef<[i32]> = rc.into();
+
+ assert_eq!(par_sum(rc), 10);
+}
+```
+
+## References into RAII locks
+
+```
+extern crate owning_ref;
+use owning_ref::RefRef;
+use std::cell::{RefCell, Ref};
+
+fn main() {
+ let refcell = RefCell::new((1, 2, 3, 4));
+ // Also works with Mutex and RwLock
+
+ let refref = {
+ let refref = RefRef::new(refcell.borrow()).map(|x| &x.3);
+ assert_eq!(*refref, 4);
+
+ // We move the RAII lock and the reference to one of
+ // the subfields in the data it guards here:
+ refref
+ };
+
+ assert_eq!(*refref, 4);
+
+ drop(refref);
+
+ assert_eq!(*refcell.borrow(), (1, 2, 3, 4));
+}
+```
+
+## Mutable reference
+
+When the owned container implements `DerefMut`, it is also possible to make
+a _mutable owning reference_. (E.g. with `Box`, `RefMut`, `MutexGuard`)
+
+```
+extern crate owning_ref;
+use owning_ref::RefMutRefMut;
+use std::cell::{RefCell, RefMut};
+
+fn main() {
+ let refcell = RefCell::new((1, 2, 3, 4));
+
+ let mut refmut_refmut = {
+ let mut refmut_refmut = RefMutRefMut::new(refcell.borrow_mut()).map_mut(|x| &mut x.3);
+ assert_eq!(*refmut_refmut, 4);
+ *refmut_refmut *= 2;
+
+ refmut_refmut
+ };
+
+ assert_eq!(*refmut_refmut, 8);
+ *refmut_refmut *= 2;
+
+ drop(refmut_refmut);
+
+ assert_eq!(*refcell.borrow(), (1, 2, 3, 16));
+}
+```
+*/
+
+extern crate stable_deref_trait;
+pub use stable_deref_trait::{StableDeref as StableAddress, CloneStableDeref as CloneStableAddress};
+
+/// An owning reference.
+///
+/// This wraps an owner `O` and a reference `&T` pointing
+/// at something reachable from `O::Target` while keeping
+/// the ability to move `self` around.
+///
+/// The owner is usually a pointer that points at some base type.
+///
+/// For more details and examples, see the module and method docs.
+pub struct OwningRef<O, T: ?Sized> {
+ owner: O,
+ reference: *const T,
+}
+
+/// An mutable owning reference.
+///
+/// This wraps an owner `O` and a reference `&mut T` pointing
+/// at something reachable from `O::Target` while keeping
+/// the ability to move `self` around.
+///
+/// The owner is usually a pointer that points at some base type.
+///
+/// For more details and examples, see the module and method docs.
+pub struct OwningRefMut<O, T: ?Sized> {
+ owner: O,
+ reference: *mut T,
+}
+
+/// Helper trait for an erased concrete type an owner dereferences to.
+/// This is used in form of a trait object for keeping
+/// something around to (virtually) call the destructor.
+pub trait Erased {}
+impl<T> Erased for T {}
+
+/// Helper trait for erasing the concrete type of what an owner derferences to,
+/// for example `Box<T> -> Box<dyn Erased>`. This would be unneeded with
+/// higher kinded types support in the language.
+pub unsafe trait IntoErased<'a> {
+ /// Owner with the dereference type substituted to `Erased`.
+ type Erased;
+ /// Perform the type erasure.
+ fn into_erased(self) -> Self::Erased;
+}
+
+/////////////////////////////////////////////////////////////////////////////
+// OwningRef
+/////////////////////////////////////////////////////////////////////////////
+
+impl<O, T: ?Sized> OwningRef<O, T> {
+ /// Creates a new owning reference from a owner
+ /// initialized to the direct dereference of it.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRef;
+ ///
+ /// fn main() {
+ /// let owning_ref = OwningRef::new(Box::new(42));
+ /// assert_eq!(*owning_ref, 42);
+ /// }
+ /// ```
+ pub fn new(o: O) -> Self
+ where O: StableAddress,
+ O: Deref<Target = T>,
+ {
+ OwningRef {
+ reference: &*o,
+ owner: o,
+ }
+ }
+
+ /// Like `new`, but doesn’t require `O` to implement the `StableAddress` trait.
+ /// Instead, the caller is responsible to make the same promises as implementing the trait.
+ ///
+ /// This is useful for cases where coherence rules prevents implementing the trait
+ /// without adding a dependency to this crate in a third-party library.
+ pub unsafe fn new_assert_stable_address(o: O) -> Self
+ where O: Deref<Target = T>,
+ {
+ OwningRef {
+ reference: &*o,
+ owner: o,
+ }
+ }
+
+ /// Converts `self` into a new owning reference that points at something reachable
+ /// from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRef;
+ ///
+ /// fn main() {
+ /// let owning_ref = OwningRef::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// // create a owning reference that points at the
+ /// // third element of the array.
+ /// let owning_ref = owning_ref.map(|array| &array[2]);
+ /// assert_eq!(*owning_ref, 3);
+ /// }
+ /// ```
+ pub fn map<F, U: ?Sized>(self, f: F) -> OwningRef<O, U>
+ where O: StableAddress,
+ F: FnOnce(&T) -> &U
+ {
+ OwningRef {
+ reference: f(&self),
+ owner: self.owner,
+ }
+ }
+
+ /// Converts `self` into a new owning reference that points at something reachable
+ /// from the previous one or from the owner itself.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U` or from the owner `O`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRef;
+ ///
+ /// fn main() {
+ /// let owning_ref = OwningRef::new(Box::new([1, 2, 3, 4]));
+ /// let owning_ref = owning_ref.map(|array| &array[2]);
+ /// assert_eq!(*owning_ref, 3);
+ ///
+ /// // create a owning reference that points at the
+ /// // second element of the array from the owning ref that was pointing to the third
+ /// let owning_ref = owning_ref.map_with_owner(|array, _prev| &array[1]);
+ /// assert_eq!(*owning_ref, 2);
+ /// }
+ /// ```
+ pub fn map_with_owner<F, U: ?Sized>(self, f: F) -> OwningRef<O, U>
+ where O: StableAddress,
+ F: for<'a> FnOnce(&'a O, &'a T) -> &'a U
+ {
+ OwningRef {
+ reference: f(&self.owner, &self),
+ owner: self.owner,
+ }
+ }
+
+ /// Tries to convert `self` into a new owning reference that points
+ /// at something reachable from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRef;
+ ///
+ /// fn main() {
+ /// let owning_ref = OwningRef::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// // create a owning reference that points at the
+ /// // third element of the array.
+ /// let owning_ref = owning_ref.try_map(|array| {
+ /// if array[2] == 3 { Ok(&array[2]) } else { Err(()) }
+ /// });
+ /// assert_eq!(*owning_ref.unwrap(), 3);
+ /// }
+ /// ```
+ pub fn try_map<F, U: ?Sized, E>(self, f: F) -> Result<OwningRef<O, U>, E>
+ where O: StableAddress,
+ F: FnOnce(&T) -> Result<&U, E>
+ {
+ Ok(OwningRef {
+ reference: f(&self)?,
+ owner: self.owner,
+ })
+ }
+
+ /// Tries to convert `self` into a new owning reference that points
+ /// at something reachable from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRef;
+ ///
+ /// fn main() {
+ /// let owning_ref = OwningRef::new(Box::new([1, 2, 3, 4]));
+ /// let owning_ref = owning_ref.map(|array| &array[2]);
+ ///
+ /// // create a owning reference that points at the
+ /// // second element of the array from the owning ref that was pointing to the third
+ /// let owning_ref = owning_ref.try_map_with_owner(|array, _prev| {
+ /// if array[1] == 2 { Ok(&array[1]) } else { Err(()) }
+ /// });
+ /// assert_eq!(*owning_ref.unwrap(), 2);
+ /// }
+ /// ```
+ pub fn try_map_with_owner<F, U: ?Sized, E>(self, f: F) -> Result<OwningRef<O, U>, E>
+ where O: StableAddress,
+ F: for<'a> FnOnce(&'a O, &'a T) -> Result<&'a U, E>
+ {
+ Ok(OwningRef {
+ reference: f(&self.owner, &self)?,
+ owner: self.owner,
+ })
+ }
+
+ /// Converts `self` into a new owning reference with a different owner type.
+ ///
+ /// The new owner type needs to still contain the original owner in some way
+ /// so that the reference into it remains valid. This function is marked unsafe
+ /// because the user needs to manually uphold this guarantee.
+ pub unsafe fn map_owner<F, P>(self, f: F) -> OwningRef<P, T>
+ where O: StableAddress,
+ P: StableAddress,
+ F: FnOnce(O) -> P
+ {
+ OwningRef {
+ reference: self.reference,
+ owner: f(self.owner),
+ }
+ }
+
+ /// Converts `self` into a new owning reference where the owner is wrapped
+ /// in an additional `Box<O>`.
+ ///
+ /// This can be used to safely erase the owner of any `OwningRef<O, T>`
+ /// to a `OwningRef<Box<dyn Erased>, T>`.
+ pub fn map_owner_box(self) -> OwningRef<Box<O>, T> {
+ OwningRef {
+ reference: self.reference,
+ owner: Box::new(self.owner),
+ }
+ }
+
+ /// Erases the concrete base type of the owner with a trait object.
+ ///
+ /// This allows mixing of owned references with different owner base types.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::{OwningRef, Erased};
+ ///
+ /// fn main() {
+ /// // NB: Using the concrete types here for explicitnes.
+ /// // For less verbose code type aliases like `BoxRef` are provided.
+ ///
+ /// let owning_ref_a: OwningRef<Box<[i32; 4]>, [i32; 4]>
+ /// = OwningRef::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// let owning_ref_b: OwningRef<Box<Vec<(i32, bool)>>, Vec<(i32, bool)>>
+ /// = OwningRef::new(Box::new(vec![(0, false), (1, true)]));
+ ///
+ /// let owning_ref_a: OwningRef<Box<[i32; 4]>, i32>
+ /// = owning_ref_a.map(|a| &a[0]);
+ ///
+ /// let owning_ref_b: OwningRef<Box<Vec<(i32, bool)>>, i32>
+ /// = owning_ref_b.map(|a| &a[1].0);
+ ///
+ /// let owning_refs: [OwningRef<Box<dyn Erased>, i32>; 2]
+ /// = [owning_ref_a.erase_owner(), owning_ref_b.erase_owner()];
+ ///
+ /// assert_eq!(*owning_refs[0], 1);
+ /// assert_eq!(*owning_refs[1], 1);
+ /// }
+ /// ```
+ pub fn erase_owner<'a>(self) -> OwningRef<O::Erased, T>
+ where O: IntoErased<'a>,
+ {
+ OwningRef {
+ reference: self.reference,
+ owner: self.owner.into_erased(),
+ }
+ }
+
+ // TODO: wrap_owner
+
+ /// A reference to the underlying owner.
+ pub fn as_owner(&self) -> &O {
+ &self.owner
+ }
+
+ /// Discards the reference and retrieves the owner.
+ pub fn into_owner(self) -> O {
+ self.owner
+ }
+}
+
+impl<O, T: ?Sized> OwningRefMut<O, T> {
+ /// Creates a new owning reference from a owner
+ /// initialized to the direct dereference of it.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRefMut;
+ ///
+ /// fn main() {
+ /// let owning_ref_mut = OwningRefMut::new(Box::new(42));
+ /// assert_eq!(*owning_ref_mut, 42);
+ /// }
+ /// ```
+ pub fn new(mut o: O) -> Self
+ where O: StableAddress,
+ O: DerefMut<Target = T>,
+ {
+ OwningRefMut {
+ reference: &mut *o,
+ owner: o,
+ }
+ }
+
+ /// Like `new`, but doesn’t require `O` to implement the `StableAddress` trait.
+ /// Instead, the caller is responsible to make the same promises as implementing the trait.
+ ///
+ /// This is useful for cases where coherence rules prevents implementing the trait
+ /// without adding a dependency to this crate in a third-party library.
+ pub unsafe fn new_assert_stable_address(mut o: O) -> Self
+ where O: DerefMut<Target = T>,
+ {
+ OwningRefMut {
+ reference: &mut *o,
+ owner: o,
+ }
+ }
+
+ /// Converts `self` into a new _shared_ owning reference that points at
+ /// something reachable from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRefMut;
+ ///
+ /// fn main() {
+ /// let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// // create a owning reference that points at the
+ /// // third element of the array.
+ /// let owning_ref = owning_ref_mut.map(|array| &array[2]);
+ /// assert_eq!(*owning_ref, 3);
+ /// }
+ /// ```
+ pub fn map<F, U: ?Sized>(mut self, f: F) -> OwningRef<O, U>
+ where O: StableAddress,
+ F: FnOnce(&mut T) -> &U
+ {
+ OwningRef {
+ reference: f(&mut self),
+ owner: self.owner,
+ }
+ }
+
+ /// Converts `self` into a new _mutable_ owning reference that points at
+ /// something reachable from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRefMut;
+ ///
+ /// fn main() {
+ /// let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// // create a owning reference that points at the
+ /// // third element of the array.
+ /// let owning_ref_mut = owning_ref_mut.map_mut(|array| &mut array[2]);
+ /// assert_eq!(*owning_ref_mut, 3);
+ /// }
+ /// ```
+ pub fn map_mut<F, U: ?Sized>(mut self, f: F) -> OwningRefMut<O, U>
+ where O: StableAddress,
+ F: FnOnce(&mut T) -> &mut U
+ {
+ OwningRefMut {
+ reference: f(&mut self),
+ owner: self.owner,
+ }
+ }
+
+ /// Tries to convert `self` into a new _shared_ owning reference that points
+ /// at something reachable from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRefMut;
+ ///
+ /// fn main() {
+ /// let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// // create a owning reference that points at the
+ /// // third element of the array.
+ /// let owning_ref = owning_ref_mut.try_map(|array| {
+ /// if array[2] == 3 { Ok(&array[2]) } else { Err(()) }
+ /// });
+ /// assert_eq!(*owning_ref.unwrap(), 3);
+ /// }
+ /// ```
+ pub fn try_map<F, U: ?Sized, E>(mut self, f: F) -> Result<OwningRef<O, U>, E>
+ where O: StableAddress,
+ F: FnOnce(&mut T) -> Result<&U, E>
+ {
+ Ok(OwningRef {
+ reference: f(&mut self)?,
+ owner: self.owner,
+ })
+ }
+
+ /// Tries to convert `self` into a new _mutable_ owning reference that points
+ /// at something reachable from the previous one.
+ ///
+ /// This can be a reference to a field of `U`, something reachable from a field of
+ /// `U`, or even something unrelated with a `'static` lifetime.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::OwningRefMut;
+ ///
+ /// fn main() {
+ /// let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// // create a owning reference that points at the
+ /// // third element of the array.
+ /// let owning_ref_mut = owning_ref_mut.try_map_mut(|array| {
+ /// if array[2] == 3 { Ok(&mut array[2]) } else { Err(()) }
+ /// });
+ /// assert_eq!(*owning_ref_mut.unwrap(), 3);
+ /// }
+ /// ```
+ pub fn try_map_mut<F, U: ?Sized, E>(mut self, f: F) -> Result<OwningRefMut<O, U>, E>
+ where O: StableAddress,
+ F: FnOnce(&mut T) -> Result<&mut U, E>
+ {
+ Ok(OwningRefMut {
+ reference: f(&mut self)?,
+ owner: self.owner,
+ })
+ }
+
+ /// Converts `self` into a new owning reference with a different owner type.
+ ///
+ /// The new owner type needs to still contain the original owner in some way
+ /// so that the reference into it remains valid. This function is marked unsafe
+ /// because the user needs to manually uphold this guarantee.
+ pub unsafe fn map_owner<F, P>(self, f: F) -> OwningRefMut<P, T>
+ where O: StableAddress,
+ P: StableAddress,
+ F: FnOnce(O) -> P
+ {
+ OwningRefMut {
+ reference: self.reference,
+ owner: f(self.owner),
+ }
+ }
+
+ /// Converts `self` into a new owning reference where the owner is wrapped
+ /// in an additional `Box<O>`.
+ ///
+ /// This can be used to safely erase the owner of any `OwningRefMut<O, T>`
+ /// to a `OwningRefMut<Box<dyn Erased>, T>`.
+ pub fn map_owner_box(self) -> OwningRefMut<Box<O>, T> {
+ OwningRefMut {
+ reference: self.reference,
+ owner: Box::new(self.owner),
+ }
+ }
+
+ /// Erases the concrete base type of the owner with a trait object.
+ ///
+ /// This allows mixing of owned references with different owner base types.
+ ///
+ /// # Example
+ /// ```
+ /// extern crate owning_ref;
+ /// use owning_ref::{OwningRefMut, Erased};
+ ///
+ /// fn main() {
+ /// // NB: Using the concrete types here for explicitnes.
+ /// // For less verbose code type aliases like `BoxRef` are provided.
+ ///
+ /// let owning_ref_mut_a: OwningRefMut<Box<[i32; 4]>, [i32; 4]>
+ /// = OwningRefMut::new(Box::new([1, 2, 3, 4]));
+ ///
+ /// let owning_ref_mut_b: OwningRefMut<Box<Vec<(i32, bool)>>, Vec<(i32, bool)>>
+ /// = OwningRefMut::new(Box::new(vec![(0, false), (1, true)]));
+ ///
+ /// let owning_ref_mut_a: OwningRefMut<Box<[i32; 4]>, i32>
+ /// = owning_ref_mut_a.map_mut(|a| &mut a[0]);
+ ///
+ /// let owning_ref_mut_b: OwningRefMut<Box<Vec<(i32, bool)>>, i32>
+ /// = owning_ref_mut_b.map_mut(|a| &mut a[1].0);
+ ///
+ /// let owning_refs_mut: [OwningRefMut<Box<dyn Erased>, i32>; 2]
+ /// = [owning_ref_mut_a.erase_owner(), owning_ref_mut_b.erase_owner()];
+ ///
+ /// assert_eq!(*owning_refs_mut[0], 1);
+ /// assert_eq!(*owning_refs_mut[1], 1);
+ /// }
+ /// ```
+ pub fn erase_owner<'a>(self) -> OwningRefMut<O::Erased, T>
+ where O: IntoErased<'a>,
+ {
+ OwningRefMut {
+ reference: self.reference,
+ owner: self.owner.into_erased(),
+ }
+ }
+
+ // TODO: wrap_owner
+
+ /// A reference to the underlying owner.
+ pub fn as_owner(&self) -> &O {
+ &self.owner
+ }
+
+ /// A mutable reference to the underlying owner.
+ pub fn as_owner_mut(&mut self) -> &mut O {
+ &mut self.owner
+ }
+
+ /// Discards the reference and retrieves the owner.
+ pub fn into_owner(self) -> O {
+ self.owner
+ }
+}
+
+/////////////////////////////////////////////////////////////////////////////
+// OwningHandle
+/////////////////////////////////////////////////////////////////////////////
+
+use std::ops::{Deref, DerefMut};
+
+/// `OwningHandle` is a complement to `OwningRef`. Where `OwningRef` allows
+/// consumers to pass around an owned object and a dependent reference,
+/// `OwningHandle` contains an owned object and a dependent _object_.
+///
+/// `OwningHandle` can encapsulate a `RefMut` along with its associated
+/// `RefCell`, or an `RwLockReadGuard` along with its associated `RwLock`.
+/// However, the API is completely generic and there are no restrictions on
+/// what types of owning and dependent objects may be used.
+///
+/// `OwningHandle` is created by passing an owner object (which dereferences
+/// to a stable address) along with a callback which receives a pointer to
+/// that stable location. The callback may then dereference the pointer and
+/// mint a dependent object, with the guarantee that the returned object will
+/// not outlive the referent of the pointer.
+///
+/// Since the callback needs to dereference a raw pointer, it requires `unsafe`
+/// code. To avoid forcing this unsafety on most callers, the `ToHandle` trait is
+/// implemented for common data structures. Types that implement `ToHandle` can
+/// be wrapped into an `OwningHandle` without passing a callback.
+pub struct OwningHandle<O, H>
+ where O: StableAddress, H: Deref,
+{
+ handle: H,
+ _owner: O,
+}
+
+impl<O, H> Deref for OwningHandle<O, H>
+ where O: StableAddress, H: Deref,
+{
+ type Target = H::Target;
+ fn deref(&self) -> &H::Target {
+ self.handle.deref()
+ }
+}
+
+unsafe impl<O, H> StableAddress for OwningHandle<O, H>
+ where O: StableAddress, H: StableAddress,
+{}
+
+impl<O, H> DerefMut for OwningHandle<O, H>
+ where O: StableAddress, H: DerefMut,
+{
+ fn deref_mut(&mut self) -> &mut H::Target {
+ self.handle.deref_mut()
+ }
+}
+
+/// Trait to implement the conversion of owner to handle for common types.
+pub trait ToHandle {
+ /// The type of handle to be encapsulated by the OwningHandle.
+ type Handle: Deref;
+
+ /// Given an appropriately-long-lived pointer to ourselves, create a
+ /// handle to be encapsulated by the `OwningHandle`.
+ unsafe fn to_handle(x: *const Self) -> Self::Handle;
+}
+
+/// Trait to implement the conversion of owner to mutable handle for common types.
+pub trait ToHandleMut {
+ /// The type of handle to be encapsulated by the OwningHandle.
+ type HandleMut: DerefMut;
+
+ /// Given an appropriately-long-lived pointer to ourselves, create a
+ /// mutable handle to be encapsulated by the `OwningHandle`.
+ unsafe fn to_handle_mut(x: *const Self) -> Self::HandleMut;
+}
+
+impl<O, H> OwningHandle<O, H>
+ where O: StableAddress, O::Target: ToHandle<Handle = H>, H: Deref,
+{
+ /// Create a new `OwningHandle` for a type that implements `ToHandle`. For types
+ /// that don't implement `ToHandle`, callers may invoke `new_with_fn`, which accepts
+ /// a callback to perform the conversion.
+ pub fn new(o: O) -> Self {
+ OwningHandle::new_with_fn(o, |x| unsafe { O::Target::to_handle(x) })
+ }
+}
+
+impl<O, H> OwningHandle<O, H>
+ where O: StableAddress, O::Target: ToHandleMut<HandleMut = H>, H: DerefMut,
+{
+ /// Create a new mutable `OwningHandle` for a type that implements `ToHandleMut`.
+ pub fn new_mut(o: O) -> Self {
+ OwningHandle::new_with_fn(o, |x| unsafe { O::Target::to_handle_mut(x) })
+ }
+}
+
+impl<O, H> OwningHandle<O, H>
+ where O: StableAddress, H: Deref,
+{
+ /// Create a new OwningHandle. The provided callback will be invoked with
+ /// a pointer to the object owned by `o`, and the returned value is stored
+ /// as the object to which this `OwningHandle` will forward `Deref` and
+ /// `DerefMut`.
+ pub fn new_with_fn<F>(o: O, f: F) -> Self
+ where F: FnOnce(*const O::Target) -> H
+ {
+ let h: H;
+ {
+ h = f(o.deref() as *const O::Target);
+ }
+
+ OwningHandle {
+ handle: h,
+ _owner: o,
+ }
+ }
+
+ /// Create a new OwningHandle. The provided callback will be invoked with
+ /// a pointer to the object owned by `o`, and the returned value is stored
+ /// as the object to which this `OwningHandle` will forward `Deref` and
+ /// `DerefMut`.
+ pub fn try_new<F, E>(o: O, f: F) -> Result<Self, E>
+ where F: FnOnce(*const O::Target) -> Result<H, E>
+ {
+ let h: H;
+ {
+ h = f(o.deref() as *const O::Target)?;
+ }
+
+ Ok(OwningHandle {
+ handle: h,
+ _owner: o,
+ })
+ }
+
+ /// A getter for the underlying owner.
+ pub fn as_owner(&self) -> &O {
+ &self._owner
+ }
+
+ /// Discards the dependent object and returns the owner.
+ pub fn into_owner(self) -> O {
+ self._owner
+ }
+}
+
+/////////////////////////////////////////////////////////////////////////////
+// std traits
+/////////////////////////////////////////////////////////////////////////////
+
+use std::convert::From;
+use std::fmt::{self, Debug};
+use std::marker::{Send, Sync};
+use std::cmp::{Eq, PartialEq, Ord, PartialOrd, Ordering};
+use std::hash::{Hash, Hasher};
+use std::borrow::Borrow;
+
+impl<O, T: ?Sized> Deref for OwningRef<O, T> {
+ type Target = T;
+
+ fn deref(&self) -> &T {
+ unsafe {
+ &*self.reference
+ }
+ }
+}
+
+impl<O, T: ?Sized> Deref for OwningRefMut<O, T> {
+ type Target = T;
+
+ fn deref(&self) -> &T {
+ unsafe {
+ &*self.reference
+ }
+ }
+}
+
+impl<O, T: ?Sized> DerefMut for OwningRefMut<O, T> {
+ fn deref_mut(&mut self) -> &mut T {
+ unsafe {
+ &mut *self.reference
+ }
+ }
+}
+
+unsafe impl<O, T: ?Sized> StableAddress for OwningRef<O, T> {}
+
+unsafe impl<O, T: ?Sized> StableAddress for OwningRefMut<O, T> {}
+
+impl<O, T: ?Sized> AsRef<T> for OwningRef<O, T> {
+ fn as_ref(&self) -> &T {
+ &*self
+ }
+}
+
+impl<O, T: ?Sized> AsRef<T> for OwningRefMut<O, T> {
+ fn as_ref(&self) -> &T {
+ &*self
+ }
+}
+
+impl<O, T: ?Sized> AsMut<T> for OwningRefMut<O, T> {
+ fn as_mut(&mut self) -> &mut T {
+ &mut *self
+ }
+}
+
+impl<O, T: ?Sized> Borrow<T> for OwningRef<O, T> {
+ fn borrow(&self) -> &T {
+ &*self
+ }
+}
+
+impl<O, T: ?Sized> From<O> for OwningRef<O, T>
+ where O: StableAddress,
+ O: Deref<Target = T>,
+{
+ fn from(owner: O) -> Self {
+ OwningRef::new(owner)
+ }
+}
+
+impl<O, T: ?Sized> From<O> for OwningRefMut<O, T>
+ where O: StableAddress,
+ O: DerefMut<Target = T>
+{
+ fn from(owner: O) -> Self {
+ OwningRefMut::new(owner)
+ }
+}
+
+impl<O, T: ?Sized> From<OwningRefMut<O, T>> for OwningRef<O, T>
+ where O: StableAddress,
+ O: DerefMut<Target = T>
+{
+ fn from(other: OwningRefMut<O, T>) -> Self {
+ OwningRef {
+ owner: other.owner,
+ reference: other.reference,
+ }
+ }
+}
+
+// ^ FIXME: Is a Into impl for calling into_owner() possible as well?
+
+impl<O, T: ?Sized> Debug for OwningRef<O, T>
+ where O: Debug,
+ T: Debug,
+{
+ fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+ write!(f,
+ "OwningRef {{ owner: {:?}, reference: {:?} }}",
+ self.as_owner(),
+ &**self)
+ }
+}
+
+impl<O, T: ?Sized> Debug for OwningRefMut<O, T>
+ where O: Debug,
+ T: Debug,
+{
+ fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+ write!(f,
+ "OwningRefMut {{ owner: {:?}, reference: {:?} }}",
+ self.as_owner(),
+ &**self)
+ }
+}
+
+impl<O, T: ?Sized> Clone for OwningRef<O, T>
+ where O: CloneStableAddress,
+{
+ fn clone(&self) -> Self {
+ OwningRef {
+ owner: self.owner.clone(),
+ reference: self.reference,
+ }
+ }
+}
+
+unsafe impl<O, T: ?Sized> CloneStableAddress for OwningRef<O, T>
+ where O: CloneStableAddress {}
+
+unsafe impl<O, T: ?Sized> Send for OwningRef<O, T>
+ where O: Send, for<'a> (&'a T): Send {}
+unsafe impl<O, T: ?Sized> Sync for OwningRef<O, T>
+ where O: Sync, for<'a> (&'a T): Sync {}
+
+unsafe impl<O, T: ?Sized> Send for OwningRefMut<O, T>
+ where O: Send, for<'a> (&'a mut T): Send {}
+unsafe impl<O, T: ?Sized> Sync for OwningRefMut<O, T>
+ where O: Sync, for<'a> (&'a mut T): Sync {}
+
+impl Debug for dyn Erased {
+ fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+ write!(f, "<dyn Erased>",)
+ }
+}
+
+impl<O, T: ?Sized> PartialEq for OwningRef<O, T> where T: PartialEq {
+ fn eq(&self, other: &Self) -> bool {
+ (&*self as &T).eq(&*other as &T)
+ }
+}
+
+impl<O, T: ?Sized> Eq for OwningRef<O, T> where T: Eq {}
+
+impl<O, T: ?Sized> PartialOrd for OwningRef<O, T> where T: PartialOrd {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ (&*self as &T).partial_cmp(&*other as &T)
+ }
+}
+
+impl<O, T: ?Sized> Ord for OwningRef<O, T> where T: Ord {
+ fn cmp(&self, other: &Self) -> Ordering {
+ (&*self as &T).cmp(&*other as &T)
+ }
+}
+
+impl<O, T: ?Sized> Hash for OwningRef<O, T> where T: Hash {
+ fn hash<H: Hasher>(&self, state: &mut H) {
+ (&*self as &T).hash(state);
+ }
+}
+
+impl<O, T: ?Sized> PartialEq for OwningRefMut<O, T> where T: PartialEq {
+ fn eq(&self, other: &Self) -> bool {
+ (&*self as &T).eq(&*other as &T)
+ }
+}
+
+impl<O, T: ?Sized> Eq for OwningRefMut<O, T> where T: Eq {}
+
+impl<O, T: ?Sized> PartialOrd for OwningRefMut<O, T> where T: PartialOrd {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ (&*self as &T).partial_cmp(&*other as &T)
+ }
+}
+
+impl<O, T: ?Sized> Ord for OwningRefMut<O, T> where T: Ord {
+ fn cmp(&self, other: &Self) -> Ordering {
+ (&*self as &T).cmp(&*other as &T)
+ }
+}
+
+impl<O, T: ?Sized> Hash for OwningRefMut<O, T> where T: Hash {
+ fn hash<H: Hasher>(&self, state: &mut H) {
+ (&*self as &T).hash(state);
+ }
+}
+
+/////////////////////////////////////////////////////////////////////////////
+// std types integration and convenience type defs
+/////////////////////////////////////////////////////////////////////////////
+
+use std::boxed::Box;
+use std::rc::Rc;
+use std::sync::Arc;
+use std::sync::{MutexGuard, RwLockReadGuard, RwLockWriteGuard};
+use std::cell::{Ref, RefCell, RefMut};
+
+impl<T: 'static> ToHandle for RefCell<T> {
+ type Handle = Ref<'static, T>;
+ unsafe fn to_handle(x: *const Self) -> Self::Handle { (*x).borrow() }
+}
+
+impl<T: 'static> ToHandleMut for RefCell<T> {
+ type HandleMut = RefMut<'static, T>;
+ unsafe fn to_handle_mut(x: *const Self) -> Self::HandleMut { (*x).borrow_mut() }
+}
+
+// NB: Implementing ToHandle{,Mut} for Mutex and RwLock requires a decision
+// about which handle creation to use (i.e. read() vs try_read()) as well as
+// what to do with error results.
+
+/// Typedef of a owning reference that uses a `Box` as the owner.
+pub type BoxRef<T, U = T> = OwningRef<Box<T>, U>;
+/// Typedef of a owning reference that uses a `Vec` as the owner.
+pub type VecRef<T, U = T> = OwningRef<Vec<T>, U>;
+/// Typedef of a owning reference that uses a `String` as the owner.
+pub type StringRef = OwningRef<String, str>;
+
+/// Typedef of a owning reference that uses a `Rc` as the owner.
+pub type RcRef<T, U = T> = OwningRef<Rc<T>, U>;
+/// Typedef of a owning reference that uses a `Arc` as the owner.
+pub type ArcRef<T, U = T> = OwningRef<Arc<T>, U>;
+
+/// Typedef of a owning reference that uses a `Ref` as the owner.
+pub type RefRef<'a, T, U = T> = OwningRef<Ref<'a, T>, U>;
+/// Typedef of a owning reference that uses a `RefMut` as the owner.
+pub type RefMutRef<'a, T, U = T> = OwningRef<RefMut<'a, T>, U>;
+/// Typedef of a owning reference that uses a `MutexGuard` as the owner.
+pub type MutexGuardRef<'a, T, U = T> = OwningRef<MutexGuard<'a, T>, U>;
+/// Typedef of a owning reference that uses a `RwLockReadGuard` as the owner.
+pub type RwLockReadGuardRef<'a, T, U = T> = OwningRef<RwLockReadGuard<'a, T>, U>;
+/// Typedef of a owning reference that uses a `RwLockWriteGuard` as the owner.
+pub type RwLockWriteGuardRef<'a, T, U = T> = OwningRef<RwLockWriteGuard<'a, T>, U>;
+
+/// Typedef of a mutable owning reference that uses a `Box` as the owner.
+pub type BoxRefMut<T, U = T> = OwningRefMut<Box<T>, U>;
+/// Typedef of a mutable owning reference that uses a `Vec` as the owner.
+pub type VecRefMut<T, U = T> = OwningRefMut<Vec<T>, U>;
+/// Typedef of a mutable owning reference that uses a `String` as the owner.
+pub type StringRefMut = OwningRefMut<String, str>;
+
+/// Typedef of a mutable owning reference that uses a `RefMut` as the owner.
+pub type RefMutRefMut<'a, T, U = T> = OwningRefMut<RefMut<'a, T>, U>;
+/// Typedef of a mutable owning reference that uses a `MutexGuard` as the owner.
+pub type MutexGuardRefMut<'a, T, U = T> = OwningRefMut<MutexGuard<'a, T>, U>;
+/// Typedef of a mutable owning reference that uses a `RwLockWriteGuard` as the owner.
+pub type RwLockWriteGuardRefMut<'a, T, U = T> = OwningRefMut<RwLockWriteGuard<'a, T>, U>;
+
+unsafe impl<'a, T: 'a> IntoErased<'a> for Box<T> {
+ type Erased = Box<dyn Erased + 'a>;
+ fn into_erased(self) -> Self::Erased {
+ self
+ }
+}
+unsafe impl<'a, T: 'a> IntoErased<'a> for Rc<T> {
+ type Erased = Rc<dyn Erased + 'a>;
+ fn into_erased(self) -> Self::Erased {
+ self
+ }
+}
+unsafe impl<'a, T: 'a> IntoErased<'a> for Arc<T> {
+ type Erased = Arc<dyn Erased + 'a>;
+ fn into_erased(self) -> Self::Erased {
+ self
+ }
+}
+
+/// Typedef of a owning reference that uses an erased `Box` as the owner.
+pub type ErasedBoxRef<U> = OwningRef<Box<dyn Erased>, U>;
+/// Typedef of a owning reference that uses an erased `Rc` as the owner.
+pub type ErasedRcRef<U> = OwningRef<Rc<dyn Erased>, U>;
+/// Typedef of a owning reference that uses an erased `Arc` as the owner.
+pub type ErasedArcRef<U> = OwningRef<Arc<dyn Erased>, U>;
+
+/// Typedef of a mutable owning reference that uses an erased `Box` as the owner.
+pub type ErasedBoxRefMut<U> = OwningRefMut<Box<dyn Erased>, U>;
+
+#[cfg(test)]
+mod tests {
+ mod owning_ref {
+ use super::super::OwningRef;
+ use super::super::{RcRef, BoxRef, Erased, ErasedBoxRef};
+ use std::cmp::{PartialEq, Ord, PartialOrd, Ordering};
+ use std::hash::{Hash, Hasher};
+ use std::collections::hash_map::DefaultHasher;
+ use std::collections::HashMap;
+ use std::rc::Rc;
+
+ #[derive(Debug, PartialEq)]
+ struct Example(u32, String, [u8; 3]);
+ fn example() -> Example {
+ Example(42, "hello world".to_string(), [1, 2, 3])
+ }
+
+ #[test]
+ fn new_deref() {
+ let or: OwningRef<Box<()>, ()> = OwningRef::new(Box::new(()));
+ assert_eq!(&*or, &());
+ }
+
+ #[test]
+ fn into() {
+ let or: OwningRef<Box<()>, ()> = Box::new(()).into();
+ assert_eq!(&*or, &());
+ }
+
+ #[test]
+ fn map_offset_ref() {
+ let or: BoxRef<Example> = Box::new(example()).into();
+ let or: BoxRef<_, u32> = or.map(|x| &x.0);
+ assert_eq!(&*or, &42);
+
+ let or: BoxRef<Example> = Box::new(example()).into();
+ let or: BoxRef<_, u8> = or.map(|x| &x.2[1]);
+ assert_eq!(&*or, &2);
+ }
+
+ #[test]
+ fn map_heap_ref() {
+ let or: BoxRef<Example> = Box::new(example()).into();
+ let or: BoxRef<_, str> = or.map(|x| &x.1[..5]);
+ assert_eq!(&*or, "hello");
+ }
+
+ #[test]
+ fn map_static_ref() {
+ let or: BoxRef<()> = Box::new(()).into();
+ let or: BoxRef<_, str> = or.map(|_| "hello");
+ assert_eq!(&*or, "hello");
+ }
+
+ #[test]
+ fn map_chained() {
+ let or: BoxRef<String> = Box::new(example().1).into();
+ let or: BoxRef<_, str> = or.map(|x| &x[1..5]);
+ let or: BoxRef<_, str> = or.map(|x| &x[..2]);
+ assert_eq!(&*or, "el");
+ }
+
+ #[test]
+ fn map_chained_inference() {
+ let or = BoxRef::new(Box::new(example().1))
+ .map(|x| &x[..5])
+ .map(|x| &x[1..3]);
+ assert_eq!(&*or, "el");
+ }
+
+ #[test]
+ fn as_owner() {
+ let or: BoxRef<String> = Box::new(example().1).into();
+ let or = or.map(|x| &x[..5]);
+ assert_eq!(&*or, "hello");
+ assert_eq!(&**or.as_owner(), "hello world");
+ }
+
+ #[test]
+ fn into_owner() {
+ let or: BoxRef<String> = Box::new(example().1).into();
+ let or = or.map(|x| &x[..5]);
+ assert_eq!(&*or, "hello");
+ let s = *or.into_owner();
+ assert_eq!(&s, "hello world");
+ }
+
+ #[test]
+ fn fmt_debug() {
+ let or: BoxRef<String> = Box::new(example().1).into();
+ let or = or.map(|x| &x[..5]);
+ let s = format!("{:?}", or);
+ assert_eq!(&s, "OwningRef { owner: \"hello world\", reference: \"hello\" }");
+ }
+
+ #[test]
+ fn erased_owner() {
+ let o1: BoxRef<Example, str> = BoxRef::new(Box::new(example()))
+ .map(|x| &x.1[..]);
+
+ let o2: BoxRef<String, str> = BoxRef::new(Box::new(example().1))
+ .map(|x| &x[..]);
+
+ let os: Vec<ErasedBoxRef<str>> = vec![o1.erase_owner(), o2.erase_owner()];
+ assert!(os.iter().all(|e| &e[..] == "hello world"));
+ }
+
+ #[test]
+ fn non_static_erased_owner() {
+ let foo = [413, 612];
+ let bar = &foo;
+
+ // FIXME: lifetime inference fails us, and we can't easily define a lifetime for a closure
+ // (see https://github.com/rust-lang/rust/issues/22340)
+ // So we use a function to identify the lifetimes instead.
+ fn borrow<'a>(a: &'a &[i32; 2]) -> &'a i32 {
+ &a[0]
+ }
+
+ let o: BoxRef<&[i32; 2]> = Box::new(bar).into();
+ let o: BoxRef<&[i32; 2], i32> = o.map(borrow);
+ let o: BoxRef<dyn Erased, i32> = o.erase_owner();
+
+ assert_eq!(*o, 413);
+ }
+
+ #[test]
+ fn raii_locks() {
+ use super::super::{RefRef, RefMutRef};
+ use std::cell::RefCell;
+ use super::super::{MutexGuardRef, RwLockReadGuardRef, RwLockWriteGuardRef};
+ use std::sync::{Mutex, RwLock};
+
+ {
+ let a = RefCell::new(1);
+ let a = {
+ let a = RefRef::new(a.borrow());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ {
+ let a = RefCell::new(1);
+ let a = {
+ let a = RefMutRef::new(a.borrow_mut());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ {
+ let a = Mutex::new(1);
+ let a = {
+ let a = MutexGuardRef::new(a.lock().unwrap());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ {
+ let a = RwLock::new(1);
+ let a = {
+ let a = RwLockReadGuardRef::new(a.read().unwrap());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ {
+ let a = RwLock::new(1);
+ let a = {
+ let a = RwLockWriteGuardRef::new(a.write().unwrap());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ }
+
+ #[test]
+ fn eq() {
+ let or1: BoxRef<[u8]> = BoxRef::new(vec![1, 2, 3].into_boxed_slice());
+ let or2: BoxRef<[u8]> = BoxRef::new(vec![1, 2, 3].into_boxed_slice());
+ assert_eq!(or1.eq(&or2), true);
+ }
+
+ #[test]
+ fn cmp() {
+ let or1: BoxRef<[u8]> = BoxRef::new(vec![1, 2, 3].into_boxed_slice());
+ let or2: BoxRef<[u8]> = BoxRef::new(vec![4, 5, 6].into_boxed_slice());
+ assert_eq!(or1.cmp(&or2), Ordering::Less);
+ }
+
+ #[test]
+ fn partial_cmp() {
+ let or1: BoxRef<[u8]> = BoxRef::new(vec![4, 5, 6].into_boxed_slice());
+ let or2: BoxRef<[u8]> = BoxRef::new(vec![1, 2, 3].into_boxed_slice());
+ assert_eq!(or1.partial_cmp(&or2), Some(Ordering::Greater));
+ }
+
+ #[test]
+ fn hash() {
+ let mut h1 = DefaultHasher::new();
+ let mut h2 = DefaultHasher::new();
+
+ let or1: BoxRef<[u8]> = BoxRef::new(vec![1, 2, 3].into_boxed_slice());
+ let or2: BoxRef<[u8]> = BoxRef::new(vec![1, 2, 3].into_boxed_slice());
+
+ or1.hash(&mut h1);
+ or2.hash(&mut h2);
+
+ assert_eq!(h1.finish(), h2.finish());
+ }
+
+ #[test]
+ fn borrow() {
+ let mut hash = HashMap::new();
+ let key = RcRef::<String>::new(Rc::new("foo-bar".to_string())).map(|s| &s[..]);
+
+ hash.insert(key.clone().map(|s| &s[..3]), 42);
+ hash.insert(key.clone().map(|s| &s[4..]), 23);
+
+ assert_eq!(hash.get("foo"), Some(&42));
+ assert_eq!(hash.get("bar"), Some(&23));
+ }
+
+ #[test]
+ fn total_erase() {
+ let a: OwningRef<Vec<u8>, [u8]>
+ = OwningRef::new(vec![]).map(|x| &x[..]);
+ let b: OwningRef<Box<[u8]>, [u8]>
+ = OwningRef::new(vec![].into_boxed_slice()).map(|x| &x[..]);
+
+ let c: OwningRef<Rc<Vec<u8>>, [u8]> = unsafe {a.map_owner(Rc::new)};
+ let d: OwningRef<Rc<Box<[u8]>>, [u8]> = unsafe {b.map_owner(Rc::new)};
+
+ let e: OwningRef<Rc<dyn Erased>, [u8]> = c.erase_owner();
+ let f: OwningRef<Rc<dyn Erased>, [u8]> = d.erase_owner();
+
+ let _g = e.clone();
+ let _h = f.clone();
+ }
+
+ #[test]
+ fn total_erase_box() {
+ let a: OwningRef<Vec<u8>, [u8]>
+ = OwningRef::new(vec![]).map(|x| &x[..]);
+ let b: OwningRef<Box<[u8]>, [u8]>
+ = OwningRef::new(vec![].into_boxed_slice()).map(|x| &x[..]);
+
+ let c: OwningRef<Box<Vec<u8>>, [u8]> = a.map_owner_box();
+ let d: OwningRef<Box<Box<[u8]>>, [u8]> = b.map_owner_box();
+
+ let _e: OwningRef<Box<dyn Erased>, [u8]> = c.erase_owner();
+ let _f: OwningRef<Box<dyn Erased>, [u8]> = d.erase_owner();
+ }
+
+ #[test]
+ fn try_map1() {
+ use std::any::Any;
+
+ let x = Box::new(123_i32);
+ let y: Box<dyn Any> = x;
+
+ OwningRef::new(y).try_map(|x| x.downcast_ref::<i32>().ok_or(())).unwrap();
+ }
+
+ #[test]
+ fn try_map2() {
+ use std::any::Any;
+
+ let x = Box::new(123_u32);
+ let y: Box<dyn Any> = x;
+
+ OwningRef::new(y).try_map(|x| x.downcast_ref::<i32>().ok_or(())).unwrap_err();
+ }
+
+ #[test]
+ fn map_with_owner() {
+ let owning_ref: BoxRef<Example> = Box::new(example()).into();
+ let owning_ref = owning_ref.map(|owner| &owner.1);
+
+ owning_ref.map_with_owner(|owner, ref_field| {
+ assert_eq!(owner.1, *ref_field);
+ ref_field
+ });
+ }
+
+ #[test]
+ fn try_map_with_owner_ok() {
+ let owning_ref: BoxRef<Example> = Box::new(example()).into();
+ let owning_ref = owning_ref.map(|owner| &owner.1);
+
+ owning_ref.try_map_with_owner(|owner, ref_field| {
+ assert_eq!(owner.1, *ref_field);
+ Ok(ref_field) as Result<_, ()>
+ }).unwrap();
+ }
+
+ #[test]
+ fn try_map_with_owner_err() {
+ let owning_ref: BoxRef<Example> = Box::new(example()).into();
+ let owning_ref = owning_ref.map(|owner| &owner.1);
+
+ owning_ref.try_map_with_owner(|owner, ref_field| {
+ assert_eq!(owner.1, *ref_field);
+ Err(()) as Result<&(), _>
+ }).unwrap_err();
+ }
+ }
+
+ mod owning_handle {
+ use super::super::OwningHandle;
+ use super::super::RcRef;
+ use std::rc::Rc;
+ use std::cell::RefCell;
+ use std::sync::Arc;
+ use std::sync::RwLock;
+
+ #[test]
+ fn owning_handle() {
+ use std::cell::RefCell;
+ let cell = Rc::new(RefCell::new(2));
+ let cell_ref = RcRef::new(cell);
+ let mut handle = OwningHandle::new_with_fn(cell_ref, |x| unsafe { x.as_ref() }.unwrap().borrow_mut());
+ assert_eq!(*handle, 2);
+ *handle = 3;
+ assert_eq!(*handle, 3);
+ }
+
+ #[test]
+ fn try_owning_handle_ok() {
+ use std::cell::RefCell;
+ let cell = Rc::new(RefCell::new(2));
+ let cell_ref = RcRef::new(cell);
+ let mut handle = OwningHandle::try_new::<_, ()>(cell_ref, |x| {
+ Ok(unsafe {
+ x.as_ref()
+ }.unwrap().borrow_mut())
+ }).unwrap();
+ assert_eq!(*handle, 2);
+ *handle = 3;
+ assert_eq!(*handle, 3);
+ }
+
+ #[test]
+ fn try_owning_handle_err() {
+ use std::cell::RefCell;
+ let cell = Rc::new(RefCell::new(2));
+ let cell_ref = RcRef::new(cell);
+ let handle = OwningHandle::try_new::<_, ()>(cell_ref, |x| {
+ if false {
+ return Ok(unsafe {
+ x.as_ref()
+ }.unwrap().borrow_mut())
+ }
+ Err(())
+ });
+ assert!(handle.is_err());
+ }
+
+ #[test]
+ fn nested() {
+ use std::cell::RefCell;
+ use std::sync::{Arc, RwLock};
+
+ let result = {
+ let complex = Rc::new(RefCell::new(Arc::new(RwLock::new("someString"))));
+ let curr = RcRef::new(complex);
+ let curr = OwningHandle::new_with_fn(curr, |x| unsafe { x.as_ref() }.unwrap().borrow_mut());
+ let mut curr = OwningHandle::new_with_fn(curr, |x| unsafe { x.as_ref() }.unwrap().try_write().unwrap());
+ assert_eq!(*curr, "someString");
+ *curr = "someOtherString";
+ curr
+ };
+ assert_eq!(*result, "someOtherString");
+ }
+
+ #[test]
+ fn owning_handle_safe() {
+ use std::cell::RefCell;
+ let cell = Rc::new(RefCell::new(2));
+ let cell_ref = RcRef::new(cell);
+ let handle = OwningHandle::new(cell_ref);
+ assert_eq!(*handle, 2);
+ }
+
+ #[test]
+ fn owning_handle_mut_safe() {
+ use std::cell::RefCell;
+ let cell = Rc::new(RefCell::new(2));
+ let cell_ref = RcRef::new(cell);
+ let mut handle = OwningHandle::new_mut(cell_ref);
+ assert_eq!(*handle, 2);
+ *handle = 3;
+ assert_eq!(*handle, 3);
+ }
+
+ #[test]
+ fn owning_handle_safe_2() {
+ let result = {
+ let complex = Rc::new(RefCell::new(Arc::new(RwLock::new("someString"))));
+ let curr = RcRef::new(complex);
+ let curr = OwningHandle::new_with_fn(curr, |x| unsafe { x.as_ref() }.unwrap().borrow_mut());
+ let mut curr = OwningHandle::new_with_fn(curr, |x| unsafe { x.as_ref() }.unwrap().try_write().unwrap());
+ assert_eq!(*curr, "someString");
+ *curr = "someOtherString";
+ curr
+ };
+ assert_eq!(*result, "someOtherString");
+ }
+ }
+
+ mod owning_ref_mut {
+ use super::super::{OwningRefMut, BoxRefMut, Erased, ErasedBoxRefMut};
+ use super::super::BoxRef;
+ use std::cmp::{PartialEq, Ord, PartialOrd, Ordering};
+ use std::hash::{Hash, Hasher};
+ use std::collections::hash_map::DefaultHasher;
+ use std::collections::HashMap;
+
+ #[derive(Debug, PartialEq)]
+ struct Example(u32, String, [u8; 3]);
+ fn example() -> Example {
+ Example(42, "hello world".to_string(), [1, 2, 3])
+ }
+
+ #[test]
+ fn new_deref() {
+ let or: OwningRefMut<Box<()>, ()> = OwningRefMut::new(Box::new(()));
+ assert_eq!(&*or, &());
+ }
+
+ #[test]
+ fn new_deref_mut() {
+ let mut or: OwningRefMut<Box<()>, ()> = OwningRefMut::new(Box::new(()));
+ assert_eq!(&mut *or, &mut ());
+ }
+
+ #[test]
+ fn mutate() {
+ let mut or: OwningRefMut<Box<usize>, usize> = OwningRefMut::new(Box::new(0));
+ assert_eq!(&*or, &0);
+ *or = 1;
+ assert_eq!(&*or, &1);
+ }
+
+ #[test]
+ fn into() {
+ let or: OwningRefMut<Box<()>, ()> = Box::new(()).into();
+ assert_eq!(&*or, &());
+ }
+
+ #[test]
+ fn map_offset_ref() {
+ let or: BoxRefMut<Example> = Box::new(example()).into();
+ let or: BoxRef<_, u32> = or.map(|x| &mut x.0);
+ assert_eq!(&*or, &42);
+
+ let or: BoxRefMut<Example> = Box::new(example()).into();
+ let or: BoxRef<_, u8> = or.map(|x| &mut x.2[1]);
+ assert_eq!(&*or, &2);
+ }
+
+ #[test]
+ fn map_heap_ref() {
+ let or: BoxRefMut<Example> = Box::new(example()).into();
+ let or: BoxRef<_, str> = or.map(|x| &mut x.1[..5]);
+ assert_eq!(&*or, "hello");
+ }
+
+ #[test]
+ fn map_static_ref() {
+ let or: BoxRefMut<()> = Box::new(()).into();
+ let or: BoxRef<_, str> = or.map(|_| "hello");
+ assert_eq!(&*or, "hello");
+ }
+
+ #[test]
+ fn map_mut_offset_ref() {
+ let or: BoxRefMut<Example> = Box::new(example()).into();
+ let or: BoxRefMut<_, u32> = or.map_mut(|x| &mut x.0);
+ assert_eq!(&*or, &42);
+
+ let or: BoxRefMut<Example> = Box::new(example()).into();
+ let or: BoxRefMut<_, u8> = or.map_mut(|x| &mut x.2[1]);
+ assert_eq!(&*or, &2);
+ }
+
+ #[test]
+ fn map_mut_heap_ref() {
+ let or: BoxRefMut<Example> = Box::new(example()).into();
+ let or: BoxRefMut<_, str> = or.map_mut(|x| &mut x.1[..5]);
+ assert_eq!(&*or, "hello");
+ }
+
+ #[test]
+ fn map_mut_static_ref() {
+ static mut MUT_S: [u8; 5] = *b"hello";
+
+ let mut_s: &'static mut [u8] = unsafe { &mut MUT_S };
+
+ let or: BoxRefMut<()> = Box::new(()).into();
+ let or: BoxRefMut<_, [u8]> = or.map_mut(move |_| mut_s);
+ assert_eq!(&*or, b"hello");
+ }
+
+ #[test]
+ fn map_mut_chained() {
+ let or: BoxRefMut<String> = Box::new(example().1).into();
+ let or: BoxRefMut<_, str> = or.map_mut(|x| &mut x[1..5]);
+ let or: BoxRefMut<_, str> = or.map_mut(|x| &mut x[..2]);
+ assert_eq!(&*or, "el");
+ }
+
+ #[test]
+ fn map_chained_inference() {
+ let or = BoxRefMut::new(Box::new(example().1))
+ .map_mut(|x| &mut x[..5])
+ .map_mut(|x| &mut x[1..3]);
+ assert_eq!(&*or, "el");
+ }
+
+ #[test]
+ fn try_map_mut() {
+ let or: BoxRefMut<String> = Box::new(example().1).into();
+ let or: Result<BoxRefMut<_, str>, ()> = or.try_map_mut(|x| Ok(&mut x[1..5]));
+ assert_eq!(&*or.unwrap(), "ello");
+
+ let or: BoxRefMut<String> = Box::new(example().1).into();
+ let or: Result<BoxRefMut<_, str>, ()> = or.try_map_mut(|_| Err(()));
+ assert!(or.is_err());
+ }
+
+ #[test]
+ fn as_owner() {
+ let or: BoxRefMut<String> = Box::new(example().1).into();
+ let or = or.map_mut(|x| &mut x[..5]);
+ assert_eq!(&*or, "hello");
+ assert_eq!(&**or.as_owner(), "hello world");
+ }
+
+ #[test]
+ fn into_owner() {
+ let or: BoxRefMut<String> = Box::new(example().1).into();
+ let or = or.map_mut(|x| &mut x[..5]);
+ assert_eq!(&*or, "hello");
+ let s = *or.into_owner();
+ assert_eq!(&s, "hello world");
+ }
+
+ #[test]
+ fn fmt_debug() {
+ let or: BoxRefMut<String> = Box::new(example().1).into();
+ let or = or.map_mut(|x| &mut x[..5]);
+ let s = format!("{:?}", or);
+ assert_eq!(&s,
+ "OwningRefMut { owner: \"hello world\", reference: \"hello\" }");
+ }
+
+ #[test]
+ fn erased_owner() {
+ let o1: BoxRefMut<Example, str> = BoxRefMut::new(Box::new(example()))
+ .map_mut(|x| &mut x.1[..]);
+
+ let o2: BoxRefMut<String, str> = BoxRefMut::new(Box::new(example().1))
+ .map_mut(|x| &mut x[..]);
+
+ let os: Vec<ErasedBoxRefMut<str>> = vec![o1.erase_owner(), o2.erase_owner()];
+ assert!(os.iter().all(|e| &e[..] == "hello world"));
+ }
+
+ #[test]
+ fn non_static_erased_owner() {
+ let mut foo = [413, 612];
+ let bar = &mut foo;
+
+ // FIXME: lifetime inference fails us, and we can't easily define a lifetime for a closure
+ // (see https://github.com/rust-lang/rust/issues/22340)
+ // So we use a function to identify the lifetimes instead.
+ fn borrow<'a>(a: &'a mut &mut [i32; 2]) -> &'a mut i32 {
+ &mut a[0]
+ }
+
+ let o: BoxRefMut<&mut [i32; 2]> = Box::new(bar).into();
+ let o: BoxRefMut<&mut [i32; 2], i32> = o.map_mut(borrow);
+ let o: BoxRefMut<dyn Erased, i32> = o.erase_owner();
+
+ assert_eq!(*o, 413);
+ }
+
+ #[test]
+ fn raii_locks() {
+ use super::super::RefMutRefMut;
+ use std::cell::RefCell;
+ use super::super::{MutexGuardRefMut, RwLockWriteGuardRefMut};
+ use std::sync::{Mutex, RwLock};
+
+ {
+ let a = RefCell::new(1);
+ let a = {
+ let a = RefMutRefMut::new(a.borrow_mut());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ {
+ let a = Mutex::new(1);
+ let a = {
+ let a = MutexGuardRefMut::new(a.lock().unwrap());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ {
+ let a = RwLock::new(1);
+ let a = {
+ let a = RwLockWriteGuardRefMut::new(a.write().unwrap());
+ assert_eq!(*a, 1);
+ a
+ };
+ assert_eq!(*a, 1);
+ drop(a);
+ }
+ }
+
+ #[test]
+ fn eq() {
+ let or1: BoxRefMut<[u8]> = BoxRefMut::new(vec![1, 2, 3].into_boxed_slice());
+ let or2: BoxRefMut<[u8]> = BoxRefMut::new(vec![1, 2, 3].into_boxed_slice());
+ assert_eq!(or1.eq(&or2), true);
+ }
+
+ #[test]
+ fn cmp() {
+ let or1: BoxRefMut<[u8]> = BoxRefMut::new(vec![1, 2, 3].into_boxed_slice());
+ let or2: BoxRefMut<[u8]> = BoxRefMut::new(vec![4, 5, 6].into_boxed_slice());
+ assert_eq!(or1.cmp(&or2), Ordering::Less);
+ }
+
+ #[test]
+ fn partial_cmp() {
+ let or1: BoxRefMut<[u8]> = BoxRefMut::new(vec![4, 5, 6].into_boxed_slice());
+ let or2: BoxRefMut<[u8]> = BoxRefMut::new(vec![1, 2, 3].into_boxed_slice());
+ assert_eq!(or1.partial_cmp(&or2), Some(Ordering::Greater));
+ }
+
+ #[test]
+ fn hash() {
+ let mut h1 = DefaultHasher::new();
+ let mut h2 = DefaultHasher::new();
+
+ let or1: BoxRefMut<[u8]> = BoxRefMut::new(vec![1, 2, 3].into_boxed_slice());
+ let or2: BoxRefMut<[u8]> = BoxRefMut::new(vec![1, 2, 3].into_boxed_slice());
+
+ or1.hash(&mut h1);
+ or2.hash(&mut h2);
+
+ assert_eq!(h1.finish(), h2.finish());
+ }
+
+ #[test]
+ fn borrow() {
+ let mut hash = HashMap::new();
+ let key1 = BoxRefMut::<String>::new(Box::new("foo".to_string())).map(|s| &s[..]);
+ let key2 = BoxRefMut::<String>::new(Box::new("bar".to_string())).map(|s| &s[..]);
+
+ hash.insert(key1, 42);
+ hash.insert(key2, 23);
+
+ assert_eq!(hash.get("foo"), Some(&42));
+ assert_eq!(hash.get("bar"), Some(&23));
+ }
+
+ #[test]
+ fn total_erase() {
+ let a: OwningRefMut<Vec<u8>, [u8]>
+ = OwningRefMut::new(vec![]).map_mut(|x| &mut x[..]);
+ let b: OwningRefMut<Box<[u8]>, [u8]>
+ = OwningRefMut::new(vec![].into_boxed_slice()).map_mut(|x| &mut x[..]);
+
+ let c: OwningRefMut<Box<Vec<u8>>, [u8]> = unsafe {a.map_owner(Box::new)};
+ let d: OwningRefMut<Box<Box<[u8]>>, [u8]> = unsafe {b.map_owner(Box::new)};
+
+ let _e: OwningRefMut<Box<dyn Erased>, [u8]> = c.erase_owner();
+ let _f: OwningRefMut<Box<dyn Erased>, [u8]> = d.erase_owner();
+ }
+
+ #[test]
+ fn total_erase_box() {
+ let a: OwningRefMut<Vec<u8>, [u8]>
+ = OwningRefMut::new(vec![]).map_mut(|x| &mut x[..]);
+ let b: OwningRefMut<Box<[u8]>, [u8]>
+ = OwningRefMut::new(vec![].into_boxed_slice()).map_mut(|x| &mut x[..]);
+
+ let c: OwningRefMut<Box<Vec<u8>>, [u8]> = a.map_owner_box();
+ let d: OwningRefMut<Box<Box<[u8]>>, [u8]> = b.map_owner_box();
+
+ let _e: OwningRefMut<Box<dyn Erased>, [u8]> = c.erase_owner();
+ let _f: OwningRefMut<Box<dyn Erased>, [u8]> = d.erase_owner();
+ }
+
+ #[test]
+ fn try_map1() {
+ use std::any::Any;
+
+ let x = Box::new(123_i32);
+ let y: Box<dyn Any> = x;
+
+ OwningRefMut::new(y).try_map_mut(|x| x.downcast_mut::<i32>().ok_or(())).unwrap();
+ }
+
+ #[test]
+ fn try_map2() {
+ use std::any::Any;
+
+ let x = Box::new(123_u32);
+ let y: Box<dyn Any> = x;
+
+ OwningRefMut::new(y).try_map_mut(|x| x.downcast_mut::<i32>().ok_or(())).unwrap_err();
+ }
+
+ #[test]
+ fn try_map3() {
+ use std::any::Any;
+
+ let x = Box::new(123_i32);
+ let y: Box<dyn Any> = x;
+
+ OwningRefMut::new(y).try_map(|x| x.downcast_ref::<i32>().ok_or(())).unwrap();
+ }
+
+ #[test]
+ fn try_map4() {
+ use std::any::Any;
+
+ let x = Box::new(123_u32);
+ let y: Box<dyn Any> = x;
+
+ OwningRefMut::new(y).try_map(|x| x.downcast_ref::<i32>().ok_or(())).unwrap_err();
+ }
+
+ #[test]
+ fn into_owning_ref() {
+ use super::super::BoxRef;
+
+ let or: BoxRefMut<()> = Box::new(()).into();
+ let or: BoxRef<()> = or.into();
+ assert_eq!(&*or, &());
+ }
+
+ struct Foo {
+ u: u32,
+ }
+ struct Bar {
+ f: Foo,
+ }
+
+ #[test]
+ fn ref_mut() {
+ use std::cell::RefCell;
+
+ let a = RefCell::new(Bar { f: Foo { u: 42 } });
+ let mut b = OwningRefMut::new(a.borrow_mut());
+ assert_eq!(b.f.u, 42);
+ b.f.u = 43;
+ let mut c = b.map_mut(|x| &mut x.f);
+ assert_eq!(c.u, 43);
+ c.u = 44;
+ let mut d = c.map_mut(|x| &mut x.u);
+ assert_eq!(*d, 44);
+ *d = 45;
+ assert_eq!(*d, 45);
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 20:51:48 +0000