| #![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!(), |
| } |
| } |