#17497 - Invalid RA diagnostic error: expected 2 arguments, found 1
Fix for #17497
The issue occurs because in some configurations of traits where one of them has `Deref` as a supertrait, RA's type inference algorithm fails to resolve the `Deref::Target` type, and instead uses a `TyKind::BoundVar` (i.e. an unknown type). This "autoderefed" type then incorrectly acts as if it implements all traits in scope.
The fix is to re-apply the same sanity-check that is done in [`iterate_method_candidates_with_autoref()`](9463d9eea4/crates/hir-ty/src/method_resolution.rs (L1008)), that is: don't try to resolve methods on unknown types. This same sanity-check is now done on each autoderefed type for which trait methods are about to be checked. If the autoderefed type is unknown, then the iterating of the trait methods for that type is skipped.
Includes a unit test that only passes after applying the fixes in this commit.
Includes a change to the assertion count in test `syntax_highlighting::tests::benchmark_syntax_highlighting_parser` as suggested by Lukas Wirth during review.
Includes a change to the sanity-check code as suggested by Florian Diebold during review.
The issue occurs because in some configurations of traits where one of them has Deref as a supertrait, RA's type inference algorithm fails to resolve the Deref::Target type, and instead uses a TyKind::BoundVar (i.e. an unknown type). This "autoderefed" type then incorrectly acts as if it implements all traits in scope.
The fix is to re-apply the same sanity-check that is done in iterate_method_candidates_with_autoref(), that is: don't try to resolve methods on unknown types. This same sanity-check is now done on each autoderefed type for which trait methods are about to be checked. If the autoderefed type is unknown, then the iterating of the trait methods for that type is skipped.
Includes a unit test that only passes after applying the fixes in this commit.
Includes a change to the assertion count in test syntax_highlighting::tests::benchmark_syntax_highlighting_parser as suggested by Lukas Wirth during review.
Includes a change to the sanity-check code as suggested by Florian Diebold during review.
Switch from `derivative` to `derive-where`
This is a part of the effort to get rid of `syn 1.*` in compiler's dependencies: #109302
Derivative has not been maintained in nearly 3 years[^1]. It also depends on `syn 1.*`.
This PR replaces `derivative` with `derive-where`[^2], a not dead alternative, which uses `syn 2.*`.
A couple of `Debug` formats have changed around the skipped fields[^3], but I doubt this is an issue.
[^1]: https://github.com/mcarton/rust-derivative/issues/117
[^2]: https://lib.rs/crates/derive-where
[^3]: See the changes in `tests/ui`
Add basic Serde serialization capabilities to Stable MIR
This PR adds basic Serde serialization capabilities to Stable MIR. It is intentionally minimal (just wrapping all stable MIR types with a Serde `derive`), so that any important design decisions can be discussed before going further. A simple test is included with this PR to validate that JSON can actually be emitted.
## Notes
When I wrapped the Stable MIR error types in `compiler/stable_mir/src/error.rs`, it caused test failures (though I'm not sure why) so I backed those out.
## Future Work
So, this PR will support serializing basic stable MIR, but it _does not_ support serializing interned values beneath `Ty`s and `AllocId`s, etc... My current thinking about how to handle this is as follows:
1. Add new `visited_X` fields to the `Tables` struct for each interned category of interest.
2. As serialization is occuring, serialize interned values as usual _and_ also record the interned value we referenced in `visited_X`.
(Possibly) In addition, if an interned value recursively references other interned values, record those interned values as well.
3. Teach the stable MIR `Context` how to access the `visited_X` values and expose them with wrappers in `stable_mir/src/lib.rs` to users (e.g. to serialize and/or further analyze them).
### Pros
This approach does not commit to any specific serialization format regarding interned values or other more complex cases, which avoids us locking into any behaviors that may not be desired long-term.
### Cons
The user will need to manually handle serializing interned values.
### Alternatives
1. We can directly provide access to the underlying `Tables` maps for interned values; the disadvantage of this approach is that it either requires extra processing for users to filter out to only use the values that they need _or_ users may serialize extra values that they don't need. The advantage is that the implementation is even simpler. The other pros/cons are similar to the above.
2. We can directly serialize interned values by expanding them in-place. The pro is that this may make some basic inputs easier to consume. However, the cons are that there will need to be special provisions for dealing with cyclical values on both the producer and consumer _and_ global values will possibly need to be de-duplicated on the consumer side.
feat: add preliminary support for `+ use<..>` `precise_capturing` syntax
## Summary
This PR adds basic support for the following syntax.
```rs
fn captures<'a: 'a, 'b: 'b, T>() -> impl Sized + use<'b, T> {}
// ~~~~~~~~~~~~~~~~~~~~~~~
// This opaque type does not capture `'a`.
fn outlives<'o, T: 'o>(_: T) {}
fn caller<'o, 'a, 'b: 'o, T: 'o>() {
// ~~
// ^ Note that we don't need `'a: 'o`.
outlives::<'o>(captures::<'a, 'b, T>());
}
```
Related to #17598
Remove Params and Fields from AstIdMap
These are too volatile, and the only reason for them seems to be for cfg diagnostics which does not carry the weight
compiler: Never debug_assert in codegen
In the name of Turing and his Hoarey heralds, assert our truths before creating a monster!
The `rustc_codegen_llvm` and `rustc_codegen_ssa` crates are fairly critical for rustc's correctness. Small mistakes here can easily result in undefined behavior, since a "small mistake" can mean something like "link and execute the wrong code". We should probably run any and all asserts in these modules unconditionally on whether this is a "debug build", and damn the costs in performance.
...Especially because the costs in performance seem to be *nothing*. It is not clear how much correctness we gain here, but I'll take free correctness improvements.
internal: add more output to the status command
Bit of a lazy change, but this is was pretty handy. I think I should clean up the configuration into something a bit more legible (maybe serialize as JSON?), but I think this is a good enough starting point that we might as well start asking people for it in issue reports.
Add method `Impl::all_in_module(…)` for allowing more localized querying
This PR is motivated by an [outside use](https://github.com/regexident/cargo-modules) of the `ra_ap_hir` crate that would benefit from being able to more efficiently query for all impls of a given module (instead of having to query for its parent crate's impls and then filtering on `impl_hir.module(db) == module_hir`).
I have the suspicion that the code as is won't quite work for file-level modules, since those don't have a block, afaict, but with all the crate-rename and version shenanigans around the `ra_ap_` release process I haven't yet been able to figure out how to patch a `ra_ap_` dependency from a third-party crate (let alone how to test this from inside of `rust-analyzer`), so haven't been able to actually run and test this. 😔
Any hints on how to make this (i.e. the code itself, as well as the testing) work are more than welcome!
