Document subdirectories of UI tests with README files
Part of rust-lang/rust#133895 and the [2025 Google Summer of Code](https://blog.rust-lang.org/2025/05/08/gsoc-2025-selected-projects/) associated project.
When adding a new UI test, one is faced with hundreds of subdirectories in `tests/ui` reflecting various categories. Knowing where to put the new test is not trivial, as many of the categories have slightly misleading names. For example, `moves` does not only refer to the `move` keyword but to functions taking ownership in general, whereas `allocator` does not refer to allocation in general but rather to the very specific `allocator_api` and `global_allocator` features.
Many contributors will therefore place their test at the top level of ̀`tests/ui` where it will be mixed with hundreds of unrelated tests.
This PR is a tentative move towards more clearly defined tag/categories, with a SUMMARY.md file documenting the true purpose of each subdirectory, placed inside `tests/ui`.
r? ``@jieyouxu``
Update cargo
7 commits in 2251525ae503fa196f6d7f9ce6d32eccb2d5f044..84709f085062cbf3c51fa507527c1b2334015178
2025-06-16 22:01:27 +0000 to 2025-06-22 23:58:39 +0000
- Bump cargo-util-schemas version (rust-lang/cargo#15696)
- test(msrv): use a far future "newer" version (rust-lang/cargo#15693)
- Plumb rustc `-Zhint-mostly-unused` flag through as a profile option (rust-lang/cargo#15643)
- Disable lldb test, which seems to be broken due to issues with lldb (rust-lang/cargo#15687)
- docs(contrib): change clap URL to docs.rs/clap (rust-lang/cargo#15682)
- feat: Introduce perma unstable `--compile-time-deps` option for `cargo build` (rust-lang/cargo#15674)
- fix: Failing tests on rustc nightly (rust-lang/cargo#15679)
Let String pass #[track_caller] to its Vec calls
I've added `#[track_caller]` to `String` methods that delegate to `Vec` methods that already have `#[track_caller]`.
I've also added `#[track_caller]` to methods that have `assert!` or `panic!` due to invalid inputs.
Skip no-op drop glue
Since rust-lang/rust#122662 this no longer gets used in vtables, so we're safe to fully
drop generating functions from vtables. Those are eventually cleaned up
by LLVM, but it's wasteful to produce them in the first place.
This doesn't appear to be a significant win (and shows some slight regressions) but
seems like the right thing to do. At minimum it reduces noise in the LLVM IR we generate,
which seems like a good thing.
Rollup of 10 pull requests
Successful merges:
- rust-lang/rust#142458 (Merge unboxed trait object error suggestion into regular dyn incompat error)
- rust-lang/rust#142593 (Add a warning to LateContext::get_def_path)
- rust-lang/rust#142594 (Add DesugaringKind::FormatLiteral)
- rust-lang/rust#142740 (Clean-up `FnCtxt::is_destruct_assignment_desugaring`)
- rust-lang/rust#142780 (Port `#[must_use]` to new attribute parsing infrastructure)
- rust-lang/rust#142798 (Don't fail to parse a struct if a semicolon is used to separate fields)
- rust-lang/rust#142856 (Add a few inline directives in rustc_serialize.)
- rust-lang/rust#142868 (remove few allow(dead_code))
- rust-lang/rust#142874 (cranelift: fix target feature name typo: "fxsr")
- rust-lang/rust#142877 (Document why tidy checks if `eslint` is installed via `npm`)
r? `@ghost`
`@rustbot` modify labels: rollup
Add a few inline directives in rustc_serialize.
I see `debug_strict_add` and `debug_strict_sub` appearing in callgrind output. This bothers me. This PR should make them disappear.
Clean-up `FnCtxt::is_destruct_assignment_desugaring`
I noticed the docstring thing and fixed that; then I thought I'd rewrite the method using let-chains while I'm at it, since that seemed appropriate. But I don't feel too strongly about the second change, so let me know if I should remove it
Add DesugaringKind::FormatLiteral
Implements `DesugaringKind::FormatLiteral` to mark the FormatArgs desugaring of format literals. The main use for this is to stop yapping about about formatting parameters if we're not anywhere near a format literal. The other use case is to fix suggestions such as https://github.com/rust-lang/rust/issues/141350. It might also be useful for new or existing diagnostics that check whether they're in a format-like macro.
cc `@xizheyin` `@fmease`
Merge unboxed trait object error suggestion into regular dyn incompat error
Another hir-walker removed from the well-formed queries. This error was always a duplicate of another, but it was able to provide more information because it could invoke `is_dyn_compatible` without worrying about cycle errors. That's also the reason we can't put the error directly into hir_ty_lowering when lowering a `dyn Trait` within an associated item signature. So instead I packed it into the error handling of wf obligation checking.
completely deduplicate `Visitor` and `MutVisitor`
r? oli-obk
This closesrust-lang/rust#127615.
### Discussion
> * Give every `MutVisitor::visit_*` method a corresponding `flat_map_*` method.
Not every AST node exists in a location where they can be mapped to multiple instances of themselves. Not every AST node exists in a location where they can be removed from existence (e.g. `filter_map_expr`). I don't think this is doable.
> * Give every `MutVisitor::visit_*` method a corresponding `Visitor` method and vice versa
The only three remaining method-level asymmetries after this PR are `visit_stmt` and `visit_nested_use_tree` (only on `Visitor`) and `visit_span` (only on `MutVisitor`).
`visit_stmt` doesn't seem applicable to `MutVisitor` because `walk_flat_map_stmt_kind` will ask `flat_map_item` / `filter_map_expr` to potentially turn a single `Stmt` to multiple based on what a visitor wants. So only using `flat_map_stmt` seems appropriate.
`visit_nested_use_tree` is used for `rustc_resolve` to track stuff. Not useful for `MutVisitor` for now.
`visit_span` is currently not used for `MutVisitor` already, it was just kept in case we want to revive rust-lang/rust#127241. cc `@cjgillot` maybe we could remove for now and re-insert later if we find a use-case? It does involve some extra effort to maintain.
* Remaining FIXMEs
`visit_lifetime` has an extra param for `Visitor` that's not in `MutVisitor`. This is again something only used by `rustc_resolve`. I think we can keep that symmetry for now.
