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#![warn(rust_2018_idioms, single_use_lifetimes)]
#![allow(dead_code)]
#[macro_use]
mod auxiliary;
use std::{
marker::{PhantomData, PhantomPinned},
panic,
pin::Pin,
};
use pin_project::{pin_project, pinned_drop, UnsafeUnpin};
#[test]
fn projection() {
#[pin_project(
project = StructProj,
project_ref = StructProjRef,
project_replace = StructProjOwn,
)]
struct Struct<T, U> {
#[pin]
f1: T,
f2: U,
}
let mut s = Struct { f1: 1, f2: 2 };
let mut s_orig = Pin::new(&mut s);
let s = s_orig.as_mut().project();
let _: Pin<&mut i32> = s.f1;
assert_eq!(*s.f1, 1);
let _: &mut i32 = s.f2;
assert_eq!(*s.f2, 2);
assert_eq!(s_orig.as_ref().f1, 1);
assert_eq!(s_orig.as_ref().f2, 2);
let mut s = Struct { f1: 1, f2: 2 };
let mut s = Pin::new(&mut s);
{
let StructProj { f1, f2 } = s.as_mut().project();
let _: Pin<&mut i32> = f1;
let _: &mut i32 = f2;
}
{
let StructProjRef { f1, f2 } = s.as_ref().project_ref();
let _: Pin<&i32> = f1;
let _: &i32 = f2;
}
{
let StructProjOwn { f1, f2 } = s.as_mut().project_replace(Struct { f1: 3, f2: 4 });
let _: PhantomData<i32> = f1;
let _: i32 = f2;
assert_eq!(f2, 2);
assert_eq!(s.f1, 3);
assert_eq!(s.f2, 4);
}
#[pin_project(project_replace)]
struct TupleStruct<T, U>(#[pin] T, U);
let mut s = TupleStruct(1, 2);
let s = Pin::new(&mut s).project();
let _: Pin<&mut i32> = s.0;
assert_eq!(*s.0, 1);
let _: &mut i32 = s.1;
assert_eq!(*s.1, 2);
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
#[derive(Eq, PartialEq, Debug)]
enum Enum<A, B, C, D> {
Tuple(#[pin] A, B),
Struct {
#[pin]
f1: C,
f2: D,
},
Unit,
}
let mut e = Enum::Tuple(1, 2);
let mut e = Pin::new(&mut e);
match e.as_mut().project() {
EnumProj::Tuple(x, y) => {
let x: Pin<&mut i32> = x;
assert_eq!(*x, 1);
let y: &mut i32 = y;
assert_eq!(*y, 2);
}
EnumProj::Struct { f1, f2 } => {
let _: Pin<&mut i32> = f1;
let _: &mut i32 = f2;
unreachable!();
}
EnumProj::Unit => unreachable!(),
}
assert_eq!(&*e, &Enum::Tuple(1, 2));
let mut e = Enum::Struct { f1: 3, f2: 4 };
let mut e = Pin::new(&mut e);
match e.as_mut().project() {
EnumProj::Tuple(x, y) => {
let _: Pin<&mut i32> = x;
let _: &mut i32 = y;
unreachable!();
}
EnumProj::Struct { f1, f2 } => {
let _: Pin<&mut i32> = f1;
assert_eq!(*f1, 3);
let _: &mut i32 = f2;
assert_eq!(*f2, 4);
}
EnumProj::Unit => unreachable!(),
}
if let EnumProj::Struct { f1, f2 } = e.as_mut().project() {
let _: Pin<&mut i32> = f1;
assert_eq!(*f1, 3);
let _: &mut i32 = f2;
assert_eq!(*f2, 4);
}
}
#[test]
fn enum_project_set() {
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
#[derive(Eq, PartialEq, Debug)]
enum Enum {
V1(#[pin] u8),
V2(bool),
}
let mut e = Enum::V1(25);
let mut e_orig = Pin::new(&mut e);
let e_proj = e_orig.as_mut().project();
match e_proj {
EnumProj::V1(val) => {
let new_e = Enum::V2(val.as_ref().get_ref() == &25);
e_orig.set(new_e);
}
EnumProj::V2(_) => unreachable!(),
}
assert_eq!(e, Enum::V2(true));
}
#[test]
fn where_clause() {
#[pin_project]
struct Struct<T>
where
T: Copy,
{
f: T,
}
#[pin_project]
struct TupleStruct<T>(T)
where
T: Copy;
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
enum Enum<T>
where
T: Copy,
{
V(T),
}
}
#[test]
fn where_clause_and_associated_type_field() {
#[pin_project(project_replace)]
struct Struct1<I>
where
I: Iterator,
{
#[pin]
f1: I,
f2: I::Item,
}
#[pin_project(project_replace)]
struct Struct2<I, J>
where
I: Iterator<Item = J>,
{
#[pin]
f1: I,
f2: J,
}
#[pin_project(project_replace)]
struct Struct3<T>
where
T: 'static,
{
f: T,
}
trait Static: 'static {}
impl<T> Static for Struct3<T> {}
#[pin_project(project_replace)]
struct TupleStruct<I>(#[pin] I, I::Item)
where
I: Iterator;
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
enum Enum<I>
where
I: Iterator,
{
V1(#[pin] I),
V2(I::Item),
}
}
#[test]
fn derive_copy() {
#[pin_project(project_replace)]
#[derive(Clone, Copy)]
struct Struct<T> {
f: T,
}
fn is_copy<T: Copy>() {}
is_copy::<Struct<u8>>();
}
#[test]
fn move_out() {
struct NotCopy;
#[pin_project(project_replace)]
struct Struct {
f: NotCopy,
}
let x = Struct { f: NotCopy };
let _val: NotCopy = x.f;
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
enum Enum {
V(NotCopy),
}
let x = Enum::V(NotCopy);
#[allow(clippy::infallible_destructuring_match)]
let _val: NotCopy = match x {
Enum::V(val) => val,
};
}
#[test]
fn trait_bounds_on_type_generics() {
#[pin_project(project_replace)]
pub struct Struct1<'a, T: ?Sized> {
f: &'a mut T,
}
#[pin_project(project_replace)]
pub struct Struct2<'a, T: ::core::fmt::Debug> {
f: &'a mut T,
}
#[pin_project(project_replace)]
pub struct Struct3<'a, T: core::fmt::Debug> {
f: &'a mut T,
}
#[pin_project(project_replace)]
pub struct Struct4<'a, T: core::fmt::Debug + core::fmt::Display> {
f: &'a mut T,
}
#[pin_project(project_replace)]
pub struct Struct5<'a, T: core::fmt::Debug + ?Sized> {
f: &'a mut T,
}
#[pin_project(project_replace)]
pub struct Struct6<'a, T: core::fmt::Debug = [u8; 16]> {
f: &'a mut T,
}
let _: Struct6<'_> = Struct6 { f: &mut [0_u8; 16] };
#[pin_project(project_replace)]
pub struct Struct7<T: 'static> {
f: T,
}
trait Static: 'static {}
impl<T> Static for Struct7<T> {}
#[pin_project(project_replace)]
pub struct Struct8<'a, 'b: 'a> {
f1: &'a u8,
f2: &'b u8,
}
#[pin_project(project_replace)]
pub struct TupleStruct<'a, T: ?Sized>(&'a mut T);
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
enum Enum<'a, T: ?Sized> {
V(&'a mut T),
}
}
#[test]
fn overlapping_lifetime_names() {
#[pin_project(project_replace)]
pub struct Struct1<'pin, T> {
#[pin]
f: &'pin mut T,
}
#[pin_project(project_replace)]
pub struct Struct2<'pin, 'pin_, 'pin__> {
#[pin]
f: &'pin &'pin_ &'pin__ (),
}
pub trait Trait<'a> {}
#[allow(single_use_lifetimes)] // https://github.com/rust-lang/rust/issues/55058
#[pin_project(project_replace)]
pub struct Hrtb<'pin___, T>
where
for<'pin> &'pin T: Unpin,
T: for<'pin> Trait<'pin>,
for<'pin, 'pin_, 'pin__> &'pin &'pin_ &'pin__ T: Unpin,
{
#[pin]
f: &'pin___ mut T,
}
#[pin_project(PinnedDrop)]
pub struct PinnedDropStruct<'pin> {
#[pin]
f: &'pin (),
}
#[pinned_drop]
impl PinnedDrop for PinnedDropStruct<'_> {
fn drop(self: Pin<&mut Self>) {}
}
#[pin_project(UnsafeUnpin)]
pub struct UnsafeUnpinStruct<'pin> {
#[pin]
f: &'pin (),
}
unsafe impl UnsafeUnpin for UnsafeUnpinStruct<'_> {}
#[pin_project(!Unpin)]
pub struct NotUnpinStruct<'pin> {
#[pin]
f: &'pin (),
}
}
#[test]
fn combine() {
#[pin_project(PinnedDrop, UnsafeUnpin)]
pub struct PinnedDropWithUnsafeUnpin<T> {
#[pin]
f: T,
}
#[pinned_drop]
impl<T> PinnedDrop for PinnedDropWithUnsafeUnpin<T> {
fn drop(self: Pin<&mut Self>) {}
}
unsafe impl<T: Unpin> UnsafeUnpin for PinnedDropWithUnsafeUnpin<T> {}
#[pin_project(PinnedDrop, !Unpin)]
pub struct PinnedDropWithNotUnpin<T> {
#[pin]
f: T,
}
#[pinned_drop]
impl<T> PinnedDrop for PinnedDropWithNotUnpin<T> {
fn drop(self: Pin<&mut Self>) {}
}
#[pin_project(UnsafeUnpin, project_replace)]
pub struct UnsafeUnpinWithReplace<T> {
#[pin]
f: T,
}
unsafe impl<T: Unpin> UnsafeUnpin for UnsafeUnpinWithReplace<T> {}
#[pin_project(!Unpin, project_replace)]
pub struct NotUnpinWithReplace<T> {
#[pin]
f: T,
}
}
#[test]
fn private_type_in_public_type() {
#[pin_project(project_replace)]
pub struct PublicStruct<T> {
#[pin]
inner: PrivateStruct<T>,
}
struct PrivateStruct<T>(T);
}
#[allow(clippy::needless_lifetimes)]
#[test]
fn lifetime_project() {
#[pin_project(project_replace)]
struct Struct1<T, U> {
#[pin]
pinned: T,
unpinned: U,
}
#[pin_project(project_replace)]
struct Struct2<'a, T, U> {
#[pin]
pinned: &'a T,
unpinned: U,
}
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
enum Enum<T, U> {
V {
#[pin]
pinned: T,
unpinned: U,
},
}
impl<T, U> Struct1<T, U> {
fn get_pin_ref<'a>(self: Pin<&'a Self>) -> Pin<&'a T> {
self.project_ref().pinned
}
fn get_pin_mut<'a>(self: Pin<&'a mut Self>) -> Pin<&'a mut T> {
self.project().pinned
}
fn get_pin_ref_elided(self: Pin<&Self>) -> Pin<&T> {
self.project_ref().pinned
}
fn get_pin_mut_elided(self: Pin<&mut Self>) -> Pin<&mut T> {
self.project().pinned
}
}
impl<'b, T, U> Struct2<'b, T, U> {
fn get_pin_ref<'a>(self: Pin<&'a Self>) -> Pin<&'a &'b T> {
self.project_ref().pinned
}
fn get_pin_mut<'a>(self: Pin<&'a mut Self>) -> Pin<&'a mut &'b T> {
self.project().pinned
}
fn get_pin_ref_elided(self: Pin<&Self>) -> Pin<&&'b T> {
self.project_ref().pinned
}
fn get_pin_mut_elided(self: Pin<&mut Self>) -> Pin<&mut &'b T> {
self.project().pinned
}
}
impl<T, U> Enum<T, U> {
fn get_pin_ref<'a>(self: Pin<&'a Self>) -> Pin<&'a T> {
match self.project_ref() {
EnumProjRef::V { pinned, .. } => pinned,
}
}
fn get_pin_mut<'a>(self: Pin<&'a mut Self>) -> Pin<&'a mut T> {
match self.project() {
EnumProj::V { pinned, .. } => pinned,
}
}
fn get_pin_ref_elided(self: Pin<&Self>) -> Pin<&T> {
match self.project_ref() {
EnumProjRef::V { pinned, .. } => pinned,
}
}
fn get_pin_mut_elided(self: Pin<&mut Self>) -> Pin<&mut T> {
match self.project() {
EnumProj::V { pinned, .. } => pinned,
}
}
}
}
mod visibility {
use pin_project::pin_project;
#[pin_project(project_replace)]
pub(crate) struct S {
pub f: u8,
}
}
#[test]
fn visibility() {
let mut x = visibility::S { f: 0 };
let x = Pin::new(&mut x);
let y = x.as_ref().project_ref();
let _: &u8 = y.f;
let y = x.project();
let _: &mut u8 = y.f;
}
#[test]
fn trivial_bounds() {
#[pin_project(project_replace)]
pub struct NoGenerics {
#[pin]
f: PhantomPinned,
}
assert_not_unpin!(NoGenerics);
}
#[test]
fn dst() {
#[pin_project]
struct Struct1<T: ?Sized> {
f: T,
}
let mut x = Struct1 { f: 0_u8 };
let x: Pin<&mut Struct1<dyn core::fmt::Debug>> = Pin::new(&mut x as _);
let _: &mut (dyn core::fmt::Debug) = x.project().f;
#[pin_project]
struct Struct2<T: ?Sized> {
#[pin]
f: T,
}
let mut x = Struct2 { f: 0_u8 };
let x: Pin<&mut Struct2<dyn core::fmt::Debug + Unpin>> = Pin::new(&mut x as _);
let _: Pin<&mut (dyn core::fmt::Debug + Unpin)> = x.project().f;
#[allow(explicit_outlives_requirements)] // https://github.com/rust-lang/rust/issues/60993
#[pin_project]
struct Struct3<T>
where
T: ?Sized,
{
f: T,
}
#[allow(explicit_outlives_requirements)] // https://github.com/rust-lang/rust/issues/60993
#[pin_project]
struct Struct4<T>
where
T: ?Sized,
{
#[pin]
f: T,
}
#[pin_project(UnsafeUnpin)]
struct Struct5<T: ?Sized> {
f: T,
}
#[pin_project(UnsafeUnpin)]
struct Struct6<T: ?Sized> {
#[pin]
f: T,
}
#[pin_project(PinnedDrop)]
struct Struct7<T: ?Sized> {
f: T,
}
#[pinned_drop]
impl<T: ?Sized> PinnedDrop for Struct7<T> {
fn drop(self: Pin<&mut Self>) {}
}
#[pin_project(PinnedDrop)]
struct Struct8<T: ?Sized> {
#[pin]
f: T,
}
#[pinned_drop]
impl<T: ?Sized> PinnedDrop for Struct8<T> {
fn drop(self: Pin<&mut Self>) {}
}
#[pin_project(!Unpin)]
struct Struct9<T: ?Sized> {
f: T,
}
#[pin_project(!Unpin)]
struct Struct10<T: ?Sized> {
#[pin]
f: T,
}
#[pin_project]
struct Struct11<'a, T: ?Sized, U: ?Sized> {
f1: &'a mut T,
f2: U,
}
#[pin_project]
struct TupleStruct1<T: ?Sized>(T);
#[pin_project]
struct TupleStruct2<T: ?Sized>(#[pin] T);
#[allow(explicit_outlives_requirements)] // https://github.com/rust-lang/rust/issues/60993
#[pin_project]
struct TupleStruct3<T>(T)
where
T: ?Sized;
#[allow(explicit_outlives_requirements)] // https://github.com/rust-lang/rust/issues/60993
#[pin_project]
struct TupleStruct4<T>(#[pin] T)
where
T: ?Sized;
#[pin_project(UnsafeUnpin)]
struct TupleStruct5<T: ?Sized>(T);
#[pin_project(UnsafeUnpin)]
struct TupleStruct6<T: ?Sized>(#[pin] T);
#[pin_project(PinnedDrop)]
struct TupleStruct7<T: ?Sized>(T);
#[pinned_drop]
impl<T: ?Sized> PinnedDrop for TupleStruct7<T> {
fn drop(self: Pin<&mut Self>) {}
}
#[pin_project(PinnedDrop)]
struct TupleStruct8<T: ?Sized>(#[pin] T);
#[pinned_drop]
impl<T: ?Sized> PinnedDrop for TupleStruct8<T> {
fn drop(self: Pin<&mut Self>) {}
}
#[pin_project(!Unpin)]
struct TupleStruct9<T: ?Sized>(T);
#[pin_project(!Unpin)]
struct TupleStruct10<T: ?Sized>(#[pin] T);
#[pin_project]
struct TupleStruct11<'a, T: ?Sized, U: ?Sized>(&'a mut T, U);
}
#[test]
fn dyn_type() {
#[pin_project]
struct Struct1 {
f: dyn core::fmt::Debug,
}
#[pin_project]
struct Struct2 {
#[pin]
f: dyn core::fmt::Debug,
}
#[pin_project]
struct Struct3 {
f: dyn core::fmt::Debug + Send,
}
#[pin_project]
struct Struct4 {
#[pin]
f: dyn core::fmt::Debug + Send,
}
#[pin_project]
struct TupleStruct1(dyn core::fmt::Debug);
#[pin_project]
struct TupleStruct2(#[pin] dyn core::fmt::Debug);
#[pin_project]
struct TupleStruct3(dyn core::fmt::Debug + Send);
#[pin_project]
struct TupleStruct4(#[pin] dyn core::fmt::Debug + Send);
}
#[allow(clippy::trailing_empty_array)] // TODO: how do we handle this? Should propagate #[repr(...)] to ProjectionOwned?
#[test]
fn parse_self() {
macro_rules! mac {
($($tt:tt)*) => {
$($tt)*
};
}
pub trait Trait {
type Assoc;
}
#[allow(clippy::type_repetition_in_bounds)]
#[pin_project(project_replace)]
pub struct Generics<T: Trait<Assoc = Self>>
where
Self: Trait<Assoc = Self>,
<Self as Trait>::Assoc: Sized,
mac!(Self): Trait<Assoc = mac!(Self)>,
{
_f: T,
}
impl<T: Trait<Assoc = Self>> Trait for Generics<T> {
type Assoc = Self;
}
#[pin_project(project_replace)]
pub struct Struct {
_f1: Box<Self>,
_f2: Box<<Self as Trait>::Assoc>,
_f3: Box<mac!(Self)>,
_f4: [(); Self::ASSOC],
_f5: [(); Self::assoc()],
_f6: [(); mac!(Self::assoc())],
}
impl Struct {
const ASSOC: usize = 1;
const fn assoc() -> usize {
0
}
}
impl Trait for Struct {
type Assoc = Self;
}
#[pin_project(project_replace)]
struct Tuple(
Box<Self>,
Box<<Self as Trait>::Assoc>,
Box<mac!(Self)>,
[(); Self::ASSOC],
[(); Self::assoc()],
[(); mac!(Self::assoc())],
);
impl Tuple {
const ASSOC: usize = 1;
const fn assoc() -> usize {
0
}
}
impl Trait for Tuple {
type Assoc = Self;
}
#[pin_project(project = EnumProj, project_ref = EnumProjRef, project_replace = EnumProjOwn)]
enum Enum {
Struct {
_f1: Box<Self>,
_f2: Box<<Self as Trait>::Assoc>,
_f3: Box<mac!(Self)>,
_f4: [(); Self::ASSOC],
_f5: [(); Self::assoc()],
_f6: [(); mac!(Self::assoc())],
},
Tuple(
Box<Self>,
Box<<Self as Trait>::Assoc>,
Box<mac!(Self)>,
[(); Self::ASSOC],
[(); Self::assoc()],
[(); mac!(Self::assoc())],
),
}
impl Enum {
const ASSOC: usize = 1;
const fn assoc() -> usize {
0
}
}
impl Trait for Enum {
type Assoc = Self;
}
}
#[test]
fn no_infer_outlives() {
trait Trait<X> {
type Y;
}
struct Struct1<A>(A);
impl<X, T> Trait<X> for Struct1<T> {
type Y = Option<T>;
}
#[pin_project(project_replace)]
struct Struct2<A, B> {
_f: <Struct1<A> as Trait<B>>::Y,
}
}
#[allow(clippy::many_single_char_names)]
#[test]
fn project_replace_panic() {
#[pin_project(project_replace)]
struct S<T, U> {
#[pin]
pinned: T,
unpinned: U,
}
struct D<'a>(&'a mut bool, bool);
impl Drop for D<'_> {
fn drop(&mut self) {
*self.0 = true;
if self.1 {
panic!();
}
}
}
let (mut a, mut b, mut c, mut d) = (false, false, false, false);
let res = panic::catch_unwind(panic::AssertUnwindSafe(|| {
let mut x = S { pinned: D(&mut a, true), unpinned: D(&mut b, false) };
let _y = Pin::new(&mut x)
.project_replace(S { pinned: D(&mut c, false), unpinned: D(&mut d, false) });
// Previous `x.pinned` was dropped and panicked when `project_replace` is
// called, so this is unreachable.
unreachable!();
}));
assert!(res.is_err());
assert!(a);
assert!(b);
assert!(c);
assert!(d);
let (mut a, mut b, mut c, mut d) = (false, false, false, false);
let res = panic::catch_unwind(panic::AssertUnwindSafe(|| {
let mut x = S { pinned: D(&mut a, false), unpinned: D(&mut b, true) };
{
let _y = Pin::new(&mut x)
.project_replace(S { pinned: D(&mut c, false), unpinned: D(&mut d, false) });
// `_y` (previous `x.unpinned`) live to the end of this scope, so
// this is not unreachable.
// unreachable!();
}
unreachable!();
}));
assert!(res.is_err());
assert!(a);
assert!(b);
assert!(c);
assert!(d);
}