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