rust/tests/ui/unused_async.rs

83 lines
1.3 KiB
Rust

#![warn(clippy::unused_async)]
#![feature(async_fn_in_trait)]
#![allow(incomplete_features)]
use std::future::Future;
use std::pin::Pin;
mod issue10800 {
#![allow(dead_code, unused_must_use, clippy::no_effect)]
use std::future::ready;
async fn async_block_await() {
async {
ready(()).await;
};
}
async fn normal_block_await() {
{
{
ready(()).await;
}
}
}
}
mod issue10459 {
trait HasAsyncMethod {
async fn do_something() -> u32;
}
impl HasAsyncMethod for () {
async fn do_something() -> u32 {
1
}
}
}
async fn foo() -> i32 {
4
}
async fn bar() -> i32 {
foo().await
}
struct S;
impl S {
async fn unused(&self) -> i32 {
1
}
async fn used(&self) -> i32 {
self.unused().await
}
}
trait AsyncTrait {
fn trait_method() -> Pin<Box<dyn Future<Output = i32>>>;
}
macro_rules! async_trait_impl {
() => {
impl AsyncTrait for S {
fn trait_method() -> Pin<Box<dyn Future<Output = i32>>> {
async fn unused() -> i32 {
5
}
Box::pin(unused())
}
}
};
}
async_trait_impl!();
fn main() {
foo();
bar();
}