needless_question_mark lint not applied to async fn

[Swatinem]

Summary

It seems like the needless_question_mark is not correctly applied to async fn, while it is applied to normal functions (obviously), and also async blocks correctly. See the reproduction below.

Lint Name

needless_question_mark

Reproducer

I tried this code:

pub fn normal_fn() -> Result<(), ()> {
    let res = Err(());
    Ok(res?) // warns
}
pub async fn async_fn() -> Result<(), ()> {
    let res = Err(());
    Ok(res?) // does not warn
}
pub fn async_block() -> impl std::future::Future<Output = Result<(), ()>> {
    async move {
        let res = Err(());
        Ok(res?) // warns
    }
}

I expected to see this happen:

All three variants should trigger a needless_question_mark lint.

Instead, this happened:

Only the normal_fn and async_block variants are triggering the lint.

warning: question mark operator is useless here
  --> src/main.rs:47:5
   |
47 |     Ok(res?) // warns
   |     ^^^^^^^^ help: try: `res`
   |
   = note: `#[warn(clippy::needless_question_mark)]` implied by `#[warn(clippy::all)]`
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_question_mark

warning: question mark operator is useless here
  --> src/main.rs:56:9
   |
56 |         Ok(res?) // warns
   |         ^^^^^^^^ help: try: `res`
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_question_mark

Version

rustc 1.58.0 (02072b482 2022-01-11)
binary: rustc
commit-hash: 02072b482a8b5357f7fb5e5637444ae30e423c40
commit-date: 2022-01-11
host: x86_64-apple-darwin
release: 1.58.0
LLVM version: 13.0.0

and

rustc 1.60.0-nightly (22e491ac7 2022-01-13)
binary: rustc
commit-hash: 22e491ac7ed454d34669151a8b6464cb643c9b41
commit-date: 2022-01-13
host: x86_64-apple-darwin
release: 1.60.0-nightly
LLVM version: 13.0.0

[loyd]

It seems that question_mark also works incorrectly.

[dswij]

@rustbot claim