5976: Complete trait impl immediately after type/const/fn r=jonas-schievink a=oxalica
Currently, we can complete type/const/fn but only if we typed an identifier.
That is, `impl .. { fn f<|> }` has completions with all trait fn including `f`, but `impl .. { fn <|> }` doesn't provide any suggestion (even if explicit trigger it).
This PR tweak the logic of completion match to make it possible.
However, we still need to explicit trigger suggestions (`Control + Space` by default) in vscode to show. Not sure if we can make it automatically triggered after typing the space after `fn`.
Another question is that I cannot figure out why `BLOCK_EXPR` need to be checked. A block expr directly inside a impl block should be invalid, and nested items will failed to locate impl block in specific offset and skip the suggestion. Now I simply removed it and no tests are broken.
4f91478e50/crates/ide/src/completion/complete_trait_impl.rs (L109)
Co-authored-by: oxalica <oxalicc@pm.me>
5971: Implement async blocks r=flodiebold a=oxalica
Fix#4018
@flodiebold already gave a generic guide in the issue. Here's some concern about implementation detail:
- Chalk doesn't support generator type yet.
- Adding generator type as a brand new type (ctor) can be complex and need to *re-introduced* builtin impls. (Like how we implement closures before native closure support of chalk, which is already removed in #5401 )
- The output type of async block should be known after type inference of the whole body.
- We cannot directly get the type from source like return-positon-impl-trait. But we still need to provide trait bounds when chalk asking for `opaque_ty_data`.
- During the inference, the output type of async block can be temporary unknown and participate the later inference.
`let a = async { None }; let _: i32 = a.await.unwrap();`
So in this PR, the type of async blocks is inferred as an opaque type parameterized by the `Future::Output` type it should be, like what we do with closure type.
And it really works now.
Well, I still have some questions:
- The bounds `AsyncBlockImplType<T>: Future<Output = T>` is currently generated in `opaque_ty_data`. I'm not sure if we should put this code here.
- Type of async block is now rendered as `impl Future<Output = OutputType>`. Do we need to special display to hint that it's a async block? Note that closure type has its special format, instead of `impl Fn(..) -> ..` or function type.
Co-authored-by: oxalica <oxalicc@pm.me>
