subtree-push nightly-2026-02-19#6807
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ytmimi merged 87 commits intorust-lang:mainfrom Feb 19, 2026
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"Missing" patterns are possible in bare fn types (`fn f(u32)`) and
similar places. Currently these are represented in the AST with
`ast::PatKind::Ident` with no `by_ref`, no `mut`, an empty ident, and no
sub-pattern. This flows through to `{hir,thir}::PatKind::Binding` for
HIR and THIR.
This is a bit nasty. It's very non-obvious, and easy to forget to check
for the exceptional empty identifier case.
This commit adds a new variant, `PatKind::Missing`, to do it properly.
The process I followed:
- Add a `Missing` variant to `{ast,hir,thir}::PatKind`.
- Chang `parse_param_general` to produce `ast::PatKind::Missing`
instead of `ast::PatKind::Missing`.
- Look through `kw::Empty` occurrences to find functions where an
existing empty ident check needs replacing with a `PatKind::Missing`
check: `print_param`, `check_trait_item`, `is_named_param`.
- Add a `PatKind::Missing => unreachable!(),` arm to every exhaustive
match identified by the compiler.
- Find which arms are actually reachable by running the test suite,
changing them to something appropriate, usually by looking at what
would happen to a `PatKind::Ident`/`PatKind::Binding` with no ref, no
`mut`, an empty ident, and no subpattern.
Quite a few of the `unreachable!()` arms were never reached. This makes
sense because `PatKind::Missing` can't happen in every pattern, only
in places like bare fn tys and trait fn decls.
I also tried an alternative approach: modifying `ast::Param::pat` to
hold an `Option<P<Pat>>` instead of a `P<Pat>`, but that quickly turned
into a very large and painful change. Adding `PatKind::Missing` is much
easier.
In the AST, currently we use `BinOpKind` within `ExprKind::AssignOp` and `AssocOp::AssignOp`, even though this allows some nonsensical combinations. E.g. there is no `&&=` operator. Likewise for HIR and THIR. This commit introduces `AssignOpKind` which only includes the ten assignable operators, and uses it in `ExprKind::AssignOp` and `AssocOp::AssignOp`. (And does similar things for `hir::ExprKind` and `thir::ExprKind`.) This avoids the possibility of nonsensical combinations, as seen by the removal of the `bug!` case in `lang_item_for_binop`. The commit is mostly plumbing, including: - Adds an `impl From<AssignOpKind> for BinOpKind` (AST) and `impl From<AssignOp> for BinOp` (MIR/THIR). - `BinOpCategory` can now be created from both `BinOpKind` and `AssignOpKind`. - Replaces the `IsAssign` type with `Op`, which has more information and a few methods. - `suggest_swapping_lhs_and_rhs`: moves the condition to the call site, it's easier that way. - `check_expr_inner`: had to factor out some code into a separate method. I'm on the fence about whether avoiding the nonsensical combinations is worth the extra code.
Add new `PatKind::Missing` variants To avoid some ugly uses of `kw::Empty` when handling "missing" patterns, e.g. in bare fn tys. Helps with #137978. Details in the individual commits. r? ``@oli-obk``
…rpolated, r=petrochenkov Remove `Nonterminal` and `TokenKind::Interpolated` A third attempt at this; the first attempt was #96724 and the second was #114647. r? `@ghost`
By replacing them with `{Open,Close}{Param,Brace,Bracket,Invisible}`.
PR #137902 made `ast::TokenKind` more like `lexer::TokenKind` by
replacing the compound `BinOp{,Eq}(BinOpToken)` variants with fieldless
variants `Plus`, `Minus`, `Star`, etc. This commit does a similar thing
with delimiters. It also makes `ast::TokenKind` more similar to
`parser::TokenType`.
This requires a few new methods:
- `TokenKind::is_{,open_,close_}delim()` replace various kinds of
pattern matches.
- `Delimiter::as_{open,close}_token_kind` are used to convert
`Delimiter` values to `TokenKind`.
Despite these additions, it's a net reduction in lines of code. This is
because e.g. `token::OpenParen` is so much shorter than
`token::OpenDelim(Delimiter::Parenthesis)` that many multi-line forms
reduce to single line forms. And many places where the number of lines
doesn't change are still easier to read, just because the names are
shorter, e.g.:
```
- } else if self.token != token::CloseDelim(Delimiter::Brace) {
+ } else if self.token != token::CloseBrace {
```
Co-authored-by: est31 <est31@users.noreply.github.com>
apparently it doesn't really use the asm parsing at present, so this may work?
Keep the `P` constructor function for now, to minimize immediate churn. All the `into_inner` calls are removed, which is nice.
So they match the order of the parts in the source code, e.g.:
```
struct Foo<T, U> { t: T, u: U }
<-><----> <------------>
/ | \
ident generics variant_data
```
Reorder `ast::ItemKind::{Struct,Enum,Union}` fields.
So they match the order of the parts in the source code, e.g.:
```
struct Foo<T, U> { t: T, u: U }
<-><----> <------------>
/ | \
ident generics variant_data
```
r? `@fee1-dead`
Reduce `ast::ptr::P` to a typedef of `Box` As per the MCP at rust-lang/compiler-team#878. r? `@fee1-dead`
"{{root}}" is an internal-only name, and cannot appear in Rust code
being formatted.
Rollup of 9 pull requests Successful merges: - rust-lang/rust#142331 (Add `trim_prefix` and `trim_suffix` methods for both `slice` and `str` types.) - rust-lang/rust#142491 (Rework #[cold] attribute parser) - rust-lang/rust#142494 (Fix missing docs in `rustc_attr_parsing`) - rust-lang/rust#142495 (Better template for `#[repr]` attributes) - rust-lang/rust#142497 (Fix random failure when JS code is executed when the whole file was not read yet) - rust-lang/rust#142575 (Ensure copy* intrinsics also perform the static self-init checks) - rust-lang/rust#142650 (Refactor Translator) - rust-lang/rust#142713 (mbe: Refactor transcription) - rust-lang/rust#142755 (rustdoc: Remove `FormatRenderer::cache`) r? `@ghost` `@rustbot` modify labels: rollup
…iscross Implement parsing of pinned borrows This PR implements part of #130494. EDIT: It introduces `&pin mut $place` and `&pin const $place` as sugars for `std::pin::pin!($place)` and its shared reference equivalent, except that `$place` will not be moved when borrowing. The borrow check will be in charge of enforcing places cannot be moved or mutably borrowed since being pinned till dropped. ### Implementation steps: - [x] parse the `&pin mut $place` and `&pin const $place` syntaxes - [ ] borrowck of `&pin mut|const` - [ ] support autoref of `&pin mut|const` when needed
New const traits syntax This PR only affects the AST and doesn't actually change anything semantically. All occurrences of `~const` outside of libcore have been replaced by `[const]`. Within libcore we have to wait for rustfmt to be bumped in the bootstrap compiler. This will happen "automatically" (when rustfmt is run) during the bootstrap bump, as rustfmt converts `~const` into `[const]`. After this we can remove the `~const` support from the parser Caveat discovered during impl: there is no legacy bare trait object recovery for `[const] Trait` as that snippet in type position goes down the slice /array parsing code and will error r? ``@fee1-dead`` cc ``@nikomatsakis`` ``@traviscross`` ``@compiler-errors``
Remove let_chains unstable feature Per rust-lang/rust#53667 (comment) (but then I also noticed rust-lang/rust#140722) This replaces the feature gate with a parser error that says let chains require 2024. A lot of tests were using the unstable feature. I either added edition:2024 to the test or split out the parts that require 2024.
`const` blocks as a `mod` item Tracking issue: rust-lang/rust#149226 This adds support for writing `const { ... }` as an item in a module. In the current implementation, this is a unique AST item that gets lowered to `const _: () = const { ... };` in HIR. rustfmt support included. TODO: - `pub const { ... }` does not make sense (see rust-lang/rust#147136). Reject it. Should this be rejected by the parser or smth? - Improve diagnostics (preferably they should not mention the fake `_` ident).
And move try_find_description to rustc_errors::codes.
…conized. Revert, but without type const. Update symbol for feature err, then update suggestion output, and lastly update tests that change because of those. Update these new tests with the correct syntax, and few existing tests with the new outputs the merge with main added. Fix for tidyfmt and some errors when manually resolving a merge conflicts. Update these tests to use update error messages and type const syntax. Update comments and error message to use new syntax instead of old type_const attribute. Remove the type_const attribute update some more tests to use the new syntax. Update these test cases. update feature gate test Change gate logic for `mgca_type_const_syntax` to work also if `min_generic_const_args` is enabled. Create a new feature gate that checks for the feature before expansion. Make rustfmt handle the `type const` syntax correctly. Add a convience method to check if a RhsKind is type const. Rename `Const` discriminant to `Body` for `ConstItemRhsKind` Give the `TraitItemKind` flag an enum instead of a simple bool to better describe what the flag is for. Update formatting for these match statements. Update clippy test to use type const syntax. Update test to use type const syntax. update rustfmt to match ast items. Update clippy to match ast and hir items. Few more test cases that used old attribute, instead of 'type const' Update to match the output from the feature gate checks. tidyfmt adjustments. Update the is_type_const, so I can constrain record!(..) in encoder.rs Update conditional compilation test. Move the feature gate to after expansion to allow for cfg(...) to work. Update some more tests to use the new syntax. Update type const tests in associated-const-bindings to use new syntax. Don't check based off the attribute, but the item here. Update some tests outside of the const_generics folder that were using #[type_const] update the tests in associated consts that use #[type_const] to use type const Update these mgca tests with the type const syntax. Add a flag to TraitItemKind for detecting type const for now. Maybe later change ItemConstRhs to have optional consts but that touches a lot more lines of code. Don't need into for these now that it's a query. Add is_type_const query to handle foreign def ids. update this test to use type const syntax. Fix logic here, we only want to lower if there is expression in this case. Update built-in macros to use ConstItemRhsKind Update more instance of the old ConstItemRhs. Rename ConstItemKind to ConstItemRhsKind, I noticed there is a typed called ConstantItemKind, so add the Rhs to the name to avoid confusion. Update lower to use ConstItemKind Add an other helper method to check if the rhs kinda has an expr. Update item parse to use ConstItemKind enum. Felt the field name could a be little clear when editing a few other things. Change the ConstItem struct see know if we have a type const or regular const. Make sure this syntax is properly feature gated.
Format heterogeneous try blocks The tracking issue for `try_blocks_heterogeneous` is rust-lang/rust#149488. This follows the formatting of homogeneous try blocks (feature `try_blocks`) by considering `try bikeshed <type>` to be the equivalent of `try` (in particular a single "token"). An alternative would be to permit breaking between `bikeshed` and `<type>`, but given that those 2 elements are an explicitly temporary part of the syntax, it doesn't seem worth it. There also doesn't seem to be any existing precedent breaking between a keyword and a type. It also doesn't seem to be useful in practice, given that the type itself doesn't break (which is how it works for the return type of closures) and has more chances to dominate the length in case a break is necessary. Happy to adapt anything in case this formatting is not optimal. The test is also copied from homogeneous try blocks with 2 additional test cases to demonstrate the behavior with long types. See [#t-lang > try blocks @ 💬](https://rust-lang.zulipchat.com/#narrow/channel/213817-t-lang/topic/try.20blocks/near/572387493) for context.
Co-authored-by: Michael Goulet <michael@errs.io>
update dependencies for the subtree-push
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We've had issues with |
Having some issues with the subtree-push related to bytecount. Hoping that bumping the version fixes that.
This is a temporary measure meant to allow rustfmt to move forward with the latest subtree-push. Currently, there are issues with `bytecount/generic-simd` on the latest nightly.
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unfortunately bumping |
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@ytmimi the fix is very simple (llogiq/bytecount#100), it's just a Disabling for now makes sense to me 👍 |
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@jieyouxu Thanks for looking into that! I think for now I want to prioritize the sync so I'm also in favor of disabling it for now. When the |
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Diff Check --edition=2024 --style-edition=2021 completed successfully ✅ Diff Check --edition=2024 --style-edition=2024 completed successfully ✅ Diff Check --edition=2021 --style-edition=2021 completed successfully ✅ Diff Check --edition=2021 --style-edition=2024 completed successfully ✅ |
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Diff-Checks leads me to believe that there won't be any issues syncing back with r-l/rust. Going to get this merged now and then we'll need to updated the CHANGELOG before the full sync. |
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This was referenced Feb 19, 2026
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Bumping the toolchain version as part of a git subtree push
current toolchain (nightly-2025-04-02):
latest toolchain (nightly-2026-02-19):