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#![warn(rust_2018_idioms, single_use_lifetimes)]
#![allow(dead_code)]
use pin_project::{pin_project, project_replace};
use std::{marker::PhantomData, pin::Pin};
#[project_replace] // Nightly does not need a dummy attribute to the function.
#[test]
fn project_replace_stmt_expr() {
#[pin_project(Replace)]
struct Struct<T, U> {
#[pin]
field1: T,
field2: U,
}
let mut s = Struct { field1: 1, field2: 2 };
#[project_replace]
let Struct { field1, field2 } =
Pin::new(&mut s).project_replace(Struct { field1: 42, field2: 43 });
let _x: PhantomData<i32> = field1;
let y: i32 = field2;
assert_eq!(y, 2);
// tuple struct
#[pin_project(Replace)]
struct TupleStruct<T, U>(#[pin] T, U);
let mut s = TupleStruct(1, 2);
#[project_replace]
let TupleStruct(x, y) = Pin::new(&mut s).project_replace(TupleStruct(42, 43));
let _x: PhantomData<i32> = x;
let y: i32 = y;
assert_eq!(y, 2);
#[pin_project(Replace)]
enum Enum<A, B, C, D> {
Variant1(#[pin] A, B),
Variant2 {
#[pin]
field1: C,
field2: D,
},
None,
}
let mut e = Enum::Variant1(1, 2);
let e = Pin::new(&mut e).project_replace(Enum::None);
#[project_replace]
match e {
Enum::Variant1(x, y) => {
let _x: PhantomData<i32> = x;
let y: i32 = y;
assert_eq!(y, 2);
}
Enum::Variant2 { field1, field2 } => {
let _x: PhantomData<i32> = field1;
let _y: i32 = field2;
panic!()
}
Enum::None => panic!(),
}
}
#[project_replace]
#[test]
fn combine() {
#[pin_project(Replace)]
enum Enum<A> {
V1(#[pin] A),
V2,
}
let mut x = Enum::V1(1);
#[project]
match Pin::new(&mut x).project() {
Enum::V1(_) => {}
Enum::V2 => unreachable!(),
}
#[project_ref]
match Pin::new(&x).project_ref() {
Enum::V1(_) => {}
Enum::V2 => unreachable!(),
}
#[project_replace]
match Pin::new(&mut x).project_replace(Enum::V2) {
Enum::V1(_) => {}
Enum::V2 => unreachable!(),
}
}
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