98 lines
2.9 KiB
Rust
98 lines
2.9 KiB
Rust
// edition:2018
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use core::future::Future;
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use core::pin::Pin;
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use core::task::{Context, Poll};
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struct T;
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struct Tuple(i32);
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struct Struct {
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a: i32
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}
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impl Struct {
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fn method(&self) {}
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}
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impl Future for Struct {
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type Output = Struct;
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fn poll(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Self::Output> { Poll::Pending }
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}
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impl Future for Tuple {
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type Output = Tuple;
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fn poll(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Self::Output> { Poll::Pending }
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}
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impl Future for T {
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type Output = Result<(), ()>;
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fn poll(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Self::Output> {
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Poll::Pending
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}
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}
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async fn foo() -> Result<(), ()> {
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Ok(())
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}
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async fn bar() -> Result<(), ()> {
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foo()?; //~ ERROR the `?` operator can only be applied to values that implement `Try`
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//~^ NOTE the `?` operator cannot be applied to type `impl Future<Output = Result<(), ()>>`
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//~| HELP the trait `Try` is not implemented for `impl Future<Output = Result<(), ()>>`
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//~| HELP consider `await`ing on the `Future`
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//~| NOTE in this expansion of desugaring of operator `?`
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//~| NOTE in this expansion of desugaring of operator `?`
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//~| NOTE in this expansion of desugaring of operator `?`
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Ok(())
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}
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async fn struct_() -> Struct {
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Struct { a: 1 }
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}
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async fn tuple() -> Tuple {
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//~^ NOTE checked the `Output` of this `async fn`, expected opaque type
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//~| NOTE while checking the return type of the `async fn`
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//~| NOTE in this expansion of desugaring of `async` block or function
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Tuple(1i32)
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}
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async fn baz() -> Result<(), ()> {
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let t = T;
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t?; //~ ERROR the `?` operator can only be applied to values that implement `Try`
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//~^ NOTE the `?` operator cannot be applied to type `T`
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//~| HELP the trait `Try` is not implemented for `T`
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//~| HELP consider `await`ing on the `Future`
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//~| NOTE in this expansion of desugaring of operator `?`
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//~| NOTE in this expansion of desugaring of operator `?`
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//~| NOTE in this expansion of desugaring of operator `?`
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let _: i32 = tuple().0; //~ ERROR no field `0`
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//~^ HELP consider `await`ing on the `Future`
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//~| NOTE field not available in `impl Future`
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let _: i32 = struct_().a; //~ ERROR no field `a`
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//~^ HELP consider `await`ing on the `Future`
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//~| NOTE field not available in `impl Future`
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struct_().method(); //~ ERROR no method named
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//~^ NOTE method not found in `impl Future<Output = Struct>`
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//~| HELP consider `await`ing on the `Future`
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Ok(())
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}
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async fn match_() {
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match tuple() { //~ HELP consider `await`ing on the `Future`
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//~^ NOTE this expression has type `impl Future<Output = Tuple>`
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Tuple(_) => {} //~ ERROR mismatched types
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//~^ NOTE expected opaque type, found `Tuple`
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//~| NOTE expected opaque type `impl Future<Output = Tuple>`
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}
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}
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fn main() {}
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