feat: More callable info
With this PR we retain more info about callables other than functions, allowing for closure parameter type inlay hints to be linkable as well as better signature help around closures and `Fn*` implementors.
When viewing traces, it's slightly confusing when the span name doesn't
match the function name. Ensure the names are consistent.
(It might be worth moving most of these to use #[tracing::instrument]
so the name can never go stale. @davidbarsky suggested that is marginally
slower, so I've just done the simple change here.)
It is bitset semantically --- many categorical things can be true about
a reference at the same time.
In parciular, a reference can be a "test" and a "write" at the same
time.
internal: Compress file text using LZ4
I haven't tested properly, but this roughly looks like:
```
1246 MB
59mb 4899 FileTextQuery
1008 MB
20mb 4899 CompressedFileTextQuery
555kb 1790 FileTextQuery
```
We might want to test on something more interesting, like `bevy`.
Add more methods for resolving definitions from AST to their corresponding HIR types
In order to be able to add these methods with consistent naming I had to also rename two existing methods that would otherwise be conflicting/confusing:
`Semantics::to_module_def(&self, file: FileId) -> Option<Module>` (before)
`Semantics::file_to_module_def(&self, file: FileId) -> Option<Module>` (after)
`Semantics::to_module_defs(&self, file: FileId) -> impl Iterator<Item = Module>` (before)
`Semantics::file_to_module_defs(&self, file: FileId) -> impl Iterator<Item = Module>` (after)
(the PR is motivated by an outside use of the `ra_ap_hir` crate that would benefit from being able to walk a `hir::Function`'s AST, resolving its exprs/stmts/items to their HIR equivalents)
fix: use 4 spaces for indentation in macro expansion
Partial fix for #16471.
In the previous code, the indentation produced by macro expansion was set to 2 spaces. This PR modifies it to 4 spaces for the sake of consistency.
performance: Speed up Method Completions By Taking Advantage of Orphan Rules
(Continues https://github.com/rust-lang/rust-analyzer/pull/16498)
This PR speeds up method completions by doing two things without regressing `analysis-stats`[^1]:
- Filter candidate traits prior to calling `iterate_path_candidates` by relying on orphan rules (see below for a slightly more in-depth explanation). When generating completions [on `slog::Logger`](5e9e59c312/common/src/ledger.rs (L78)) in `oxidecomputer/omicron` as a test, this PR halved my completion times—it's now 454ms cold and 281ms warm. Before this PR, it was 808ms cold and 579ms warm.
- Inline some of the method candidate checks into `is_valid_method_candidate` and remove some unnecessary visibility checks. This was suggested by `@Veykril` in [this comment](https://github.com/rust-lang/rust-analyzer/pull/16498#issuecomment-1929864427).
We filter candidate traits by taking advantage of orphan rules. For additional details, I'll rely on `@WaffleLapkin's` explanation [from Zulip](https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Frust-analyzer/topic/Trait.20Checking/near/420942417):
> A type `A` can only implements traits which
> 1. Have a blanket implementation (`impl<T> Trait for T {}`)
> 2. Have implementation for `A` (`impl Trait for A {}`)
>
> Blanket implementation can only exist in `Trait`'s crate. Implementation for `A` can only exist in `A`'s or `Trait`'s crate.
Big thanks to Waffle for its keen observation!
---
I think some additional improvements are possible:
- `for_trait_and_self_ty` seemingly does not distinguish between `&T`, `&mut T`, or `T`, resulting in seemingly irrelevant traits like `tokio::io::AsyncWrite` being being included for, e.g., `&slog::Logger`. I don't know they're being considered due to the [autoref/autoderef behavior](a02a219773/crates/hir-ty/src/method_resolution.rs (L945-L962)), but I wonder if it'd make sense to filter by mutability earlier and not consider trait implementations that require `&mut T` when we only have a `&T`.
- The method completions [spend a _lot_ of time in unification](https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Frust-analyzer/topic/Trait.20Checking/near/421072356), and while there might be low-hanging fruit there, it might make more sense to wait for the new trait solver in `rustc`. I dunno.
[^1]: The filtering occurs outside of typechecking, after all.
