Can actually split out adding the functions from getting the impl to
update or create thanks to being able to refer to the impl ast node.
FIXME Context:
Unfortunately we can't adjust the indentation of the newly added function
inside of `ast::AssocItemList::add_item` since for some reason the `todo!()`
placeholder generated by `add_missing_impl_members` and
`replace_derive_with_manual_impl` gets indented weirdly.
fix: generate async delegate methods
Fixes a bug where the generated async method doesn't await the result before returning it.
This is an example of what the output looked like:
```rust
struct Age<T>(T);
impl<T> Age<T> {
pub(crate) async fn age<J, 'a>(&'a mut self, ty: T, arg: J) -> T {
self.0
}
}
struct Person<T> {
age: Age<T>,
}
impl<T> Person<T> {
pub(crate) async fn age<J, 'a>(&'a mut self, ty: T, arg: J) -> T {
self.age.age(ty, arg) // .await is missing
}
}
```
The `.await` is missing, so the return type is `impl Future<Output = T>` instead of `T`
This makes code more readale and concise,
moving all format arguments like `format!("{}", foo)`
into the more compact `format!("{foo}")` form.
The change was automatically created with, so there are far less change
of an accidental typo.
```
cargo clippy --fix -- -A clippy::all -W clippy::uninlined_format_args
```
