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#![warn(unsafe_code)]
#![warn(rust_2018_idioms, single_use_lifetimes)]
#![allow(dead_code)]
use pin_project::{pin_project, project_ref};
use std::pin::Pin;
#[project_ref] // Nightly does not need a dummy attribute to the function.
#[test]
fn project_stmt_expr() {
// struct
#[pin_project]
struct Foo<T, U> {
#[pin]
field1: T,
field2: U,
}
let foo = Foo { field1: 1, field2: 2 };
#[project_ref]
let Foo { field1, field2 } = Pin::new(&foo).project_ref();
let x: Pin<&i32> = field1;
assert_eq!(*x, 1);
let y: &i32 = field2;
assert_eq!(*y, 2);
// tuple struct
#[pin_project]
struct Bar<T, U>(#[pin] T, U);
let bar = Bar(1, 2);
#[project_ref]
let Bar(x, y) = Pin::new(&bar).project_ref();
let x: Pin<&i32> = x;
assert_eq!(*x, 1);
let y: &i32 = y;
assert_eq!(*y, 2);
// enum
#[pin_project]
enum Baz<A, B, C, D> {
Variant1(#[pin] A, B),
Variant2 {
#[pin]
field1: C,
field2: D,
},
None,
}
let baz = Baz::Variant1(1, 2);
let baz = Pin::new(&baz).project_ref();
#[project_ref]
match &baz {
Baz::Variant1(x, y) => {
let x: &Pin<&i32> = x;
assert_eq!(**x, 1);
let y: &&i32 = y;
assert_eq!(**y, 2);
}
Baz::Variant2 { field1, field2 } => {
let _x: &Pin<&i32> = field1;
let _y: &&i32 = field2;
}
Baz::None => {}
}
#[project_ref]
let val = match &baz {
Baz::Variant1(_, _) => true,
Baz::Variant2 { .. } => false,
Baz::None => false,
};
assert_eq!(val, true);
}
#[test]
fn project_impl() {
#[pin_project]
struct HasGenerics<T, U> {
#[pin]
field1: T,
field2: U,
}
#[project_ref]
impl<T, U> HasGenerics<T, U> {
fn a(self) {
let Self { field1, field2 } = self;
let _x: Pin<&T> = field1;
let _y: &U = field2;
}
}
#[pin_project]
struct NoneGenerics {
#[pin]
field1: i32,
field2: u32,
}
#[project_ref]
impl NoneGenerics {}
#[pin_project]
struct HasLifetimes<'a, T, U> {
#[pin]
field1: &'a mut T,
field2: U,
}
#[project_ref]
impl<T, U> HasLifetimes<'_, T, U> {}
#[pin_project]
struct HasOverlappingLifetimes<'pin, T, U> {
#[pin]
field1: &'pin mut T,
field2: U,
}
#[allow(single_use_lifetimes)]
#[project_ref]
impl<'pin, T, U> HasOverlappingLifetimes<'pin, T, U> {}
#[pin_project]
struct HasOverlappingLifetimes2<T, U> {
#[pin]
field1: T,
field2: U,
}
#[allow(single_use_lifetimes)]
#[project_ref]
impl<T, U> HasOverlappingLifetimes2<T, U> {
fn foo<'pin>(&'pin self) {}
}
}
|
