Incorrect type hints for async closures (nightly feature async_closure).

[zachs18]

Rust-analyzer shows incorrect type hints for async closures (nightly feature, tracking issue).

#![feature(async_closure)]
pub async fn test_async_closure() {
    let f = async move |num: u8| num + 1;
    let fut = f(3);
    let output = fut.await;
}
pub async fn test_closure_returning_async_block() {
    let f = |num: u8| async move {num + 1};
    let fut = f(3);
    let output = fut.await;
}

RA gives following the inlay hints:

pub async fn test_async_closure() { // Incorrect
    let f: |u8| -> u8 = async move |num: u8| num + 1;
    let fut: u8 = f(3);
    let output: <u8 as Future>::Output = fut.await;
}
pub async fn test_closure_returning_async_block() { // Correct
    let f: |u8| -> impl Future<Output = u8> = |num: u8| async move {num + 1};
    let fut: impl Future<Output = u8> = f(3);
    let output: u8 = fut.await;
}

(No type errors are given, despite u8: !Future)

The inlay hints for test_async_closure should be the same as test_closure_returning_async_block.

---

rust-analyzer version: rust-analyzer version: 0.4.1159-standalone (3792720 2022-08-05)
Also happens on current HEAD

rustc version: rustc 1.64.0-nightly (1b57946a4 2022-08-03)

relevant settings: None that I am aware are relevant.