Commit Graph

866 Commits

Author SHA1 Message Date
Esteban Küber 3b27a36601 Suggest appropriate spaces around = in let binding parse error 2026-03-20 19:45:29 +00:00
Esteban Küber 244322f0be Make : -> = typo suggestion verbose 2026-03-20 19:07:28 +00:00
Esteban Küber 87d8f5885b Provide more context on type errors in const context
- On `const` and `static` point at the type (like we do for let bindings)
- On fn calls, point at const parameter in fn definition
- On type, point at const parameter in type definition
- On array type lengths, explain that array length is always `usize`
- On enum variant discriminant, mention `repr`
2026-03-14 20:13:43 +00:00
cyrgani 9e97c57cc8 relocate several ui tests 2026-03-13 10:00:39 +00:00
Jonathan Brouwer cecc5e7cea Rollup merge of #153346 - WaffleLapkin:sometimes-test, r=jieyouxu
move never type tests to subdirectories and add some comments

This hopefully makes things a little bit clearer
2026-03-07 01:42:36 +01:00
Waffle Lapkin 05174fbcc5 tidy never type issue-* tests 2026-03-06 17:44:18 +01:00
Waffle Lapkin eef3c4db7b move never type tests to subdirectories and add some comments 2026-03-04 13:17:19 +01:00
Stuart Cook 70287b9bc2 Rollup merge of #153048 - ozankenangungor:fix-irrefutable-let-else-wording, r=Kivooeo
Improve irrefutable let-else lint wording

Update the `irrefutable_let_patterns` wording for let-else to better reflect that the `else` clause is unreachable when the LHS pattern always matches.

Closes rust-lang/rust#152938
2026-03-04 11:54:09 +11:00
Jonathan Brouwer 87bd517707 Rollup merge of #153034 - arferreira:fix-trivial-bound-diagnostic, r=Kivooeo
Remove unhelpful hint from trivial bound errors

The `= help: see issue #48214` hint on trivial bound errors isn't useful, most users hitting these errors aren't trying to use the `trivial_bounds` feature. The `disabled_nightly_features` call already handles suggesting the feature gate on nightly.

Closes rust-lang/rust#152872
2026-03-03 07:14:15 +01:00
Ozan Kenan Güngör a8d4eeef1b Improve irrefutable let-else lint wording 2026-03-03 03:39:56 +03:00
Kevin Reid f5d3b158b9 Don’t report missing fields in struct exprs with syntax errors.
This prevents spurious errors when a field is intended to be present
but a preceding syntax error caused it not to be parsed. For example,

    StructName { foo: 1 bar: 2 }

will not successfully parse a field `bar`, and we will report the syntax
error but not the missing field.
2026-02-28 20:32:20 -08:00
bors 6f54d591c3 Auto merge of #151247 - chenyukang:yukang-fix-const-recover-151149, r=estebank
Try to recover from over-parsing in const item with missing semicolon

Fixes rust-lang/rust#151149

r? @estebank
2026-02-27 09:09:21 +00:00
arferreira d3bd9e6103 Remove unhelpful hint from trivial bound errors 2026-02-24 00:04:45 -05:00
Jonathan Brouwer 0b5290123d Update uitests 2026-02-22 20:20:33 +01:00
Jonathan Brouwer 9330931a2b Rollup merge of #152596 - estebank:multipart_suggestions, r=petrochenkov
Make all multipart suggestions verbose

The ShowAlways style of suggestions is usually easier to understand than the inline style.
2026-02-19 10:56:37 +01:00
bors e0cb264b81 Auto merge of #141295 - Kivooeo:if-let-guard-stable, r=fee1-dead,est31
Stabilize `if let` guards (`feature(if_let_guard)`)



## Summary

This proposes the stabilization of `if let` guards (tracking issue: rust-lang/rust#51114, RFC: rust-lang/rfcs#2294). This feature allows `if let` expressions to be used directly within match arm guards, enabling conditional pattern matching within guard clauses.

## What is being stabilized

The ability to use `if let` expressions within match arm guards.

Example:

```rust
enum Command {
    Run(String),
    Stop,
    Pause,
}

fn process_command(cmd: Command, state: &mut String) {
    match cmd {
        Command::Run(name) if let Some(first_char) = name.chars().next() && first_char.is_ascii_alphabetic() => {
            // Both `name` and `first_char` are available here
            println!("Running command: {} (starts with '{}')", name, first_char);
            state.push_str(&format!("Running {}", name));
        }
        Command::Run(name) => {
            println!("Cannot run command '{}'. Invalid name.", name);
        }
        Command::Stop if state.contains("running") => {
            println!("Stopping current process.");
            state.clear();
        }
        _ => {
            println!("Unhandled command or state.");
        }
    }
}
```

## Motivation

The primary motivation for `if let` guards is to reduce nesting and improve readability when conditional logic depends on pattern matching. Without this feature, such logic requires nested `if let` statements within match arms:

```rust
// Without if let guards
match value {
    Some(x) => {
        if let Ok(y) = compute(x) {
            // Both `x` and `y` are available here
            println!("{}, {}", x, y);
        }
    }
    _ => {}
}

// With if let guards
match value {
    Some(x) if let Ok(y) = compute(x) => {
        // Both `x` and `y` are available here
        println!("{}, {}", x, y);
    }
    _ => {}
}
```

## Implementation and Testing

The feature has been implemented and tested comprehensively across different scenarios:

### Core Functionality Tests

**Scoping and variable binding:**
- [`scope.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/scope.rs) - Verifies that bindings created in `if let` guards are properly scoped and available in match arms
- [`shadowing.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/shadowing.rs) - Tests that variable shadowing works correctly within guards
- [`scoping-consistency.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/scoping-consistency.rs) - Ensures temporaries in guards remain valid for the duration of their match arms

**Type system integration:**
- [`type-inference.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/type-inference.rs) - Confirms type inference works correctly in `if let` guards  
- [`typeck.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/typeck.rs) - Verifies type mismatches are caught appropriately

**Pattern matching semantics:**
- [`exhaustive.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.rs) - Validates that `if let` guards are correctly handled in exhaustiveness analysis
- [`move-guard-if-let.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/move-guard-if-let.rs) and [`move-guard-if-let-chain.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/move-guard-if-let-chain.rs) - Test that conditional moves in guards are tracked correctly by the borrow checker

### Error Handling and Diagnostics

- [`warns.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/warns.rs) - Tests warnings for irrefutable patterns and unreachable code in guards
- [`parens.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs) - Ensures parentheses around `let` expressions are properly rejected
- [`macro-expanded.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.rs) - Verifies macro expansions that produce invalid constructs are caught
- [`guard-mutability-2.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.rs) - Tests mutability and ownership violations in guards
- [`ast-validate-guards.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2497-if-let-chains/ast-validate-guards.rs) - Validates AST-level syntax restrictions

### Drop Order and Temporaries

**Key insight:** Unlike `let_chains` in regular `if` expressions, `if let` guards do not have drop order inconsistencies because:
1. Match guards are clearly scoped to their arms
2. There is no "else block" equivalent that could cause temporal confusion

- [`drop-order.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/drop-order.rs) - Check drop order of temporaries create in match guards
- [`compare-drop-order.rs`](https://github.com/rust-lang/rust/blob/aef3f5fdf052fbbc16e174aef5da6d50832ca316/tests/ui/rfcs/rfc-2294-if-let-guard/compare-drop-order.rs) - Compares drop order between `if let` guards and nested `if let` in match arms, confirming they behave identically across all editions
- rust-lang/rust#140981 - A complicated drop order test involved `let chain` was made by @est31
- [`drop-order-comparisons-let-chains.rs`](https://github.com/rust-lang/rust/blob/902b4d28783e03e231d8513082cc30c4fcce5d95/tests/ui/drop/drop-order-comparisons-let-chains.rs) - Compares drop order between `let chains` in `if let guard` and regular `if` expressions
- [`if-let-guards.rs`](https://github.com/rust-lang/rust/blob/5650d716e0589e2e145ce9027f35bd534e5f862a/tests/ui/drop/if-let-guards.rs) - Test correctness of drop order for bindings and temporaries
- [`if-let-guards-2`](https://github.com/rust-lang/rust/blob/3a6c8c8f3d7ae654fdb6ce1255182bda21680655/tests/ui/drop/if-let-guards-2.rs) - The same test as above but more comprehensive and tests more interactions between different features and their drop order, checking that drop order is correct, created by @traviscross 

## Edition Compatibility

This feature stabilizes on all editions, unlike `let chains` which was limited to edition 2024. This is safe because:

1. `if let` guards don't suffer from the drop order issues that affected `let chains` in regular `if` expressions
2. The scoping is unambiguous - guards are clearly tied to their match arms
3. Extensive testing confirms identical behavior across all editions

## Interactions with Future Features

The lang team has reviewed potential interactions with planned "guard patterns" and determined that stabilizing `if let` guards now does not create obstacles for future work. The scoping and evaluation semantics established here align with what guard patterns will need.

## Unresolved Issues

- [x] - rust-lang/rust#140981
- [x] - added tests description by @jieyouxu request
- [x] - Concers from @scottmcm about stabilizing this across all editions
- [x] - check if drop order in all edition when using `let chains` inside `if let` guard is the same
- [x] - interactions with guard patters
- [x] - pattern bindings drops before guard bindings https://github.com/rust-lang/rust/pull/143376
- [x] - documentaion (https://github.com/rust-lang/reference/pull/1957)
- [ ] (non-blocking) add tests for [this](https://github.com/rust-lang/rust/issues/145237) and [this](https://github.com/rust-lang/rust/pull/141295#issuecomment-3173059821)

---

**Related:**
- Tracking Issue: rust-lang/rust#51114  
- RFC: rust-lang/rfcs#2294
- Documentation PR: https://github.com/rust-lang/reference/pull/1957
2026-02-18 20:49:50 +00:00
Esteban Küber 37684bdfc5 Make all multipart suggestions verbose
The ShowAlways style of suggestions is usually easier to understand than the inline style.
2026-02-18 18:33:35 +00:00
Esteban Küber c73b3d20c6 Unify wording of resolve error
Remove "failed to resolve" and use the same format we use in other resolution errors "cannot find `name`".

```
error[E0433]: cannot find `nonexistent` in `existent`
  --> $DIR/custom_attr_multisegment_error.rs:5:13
   |
LL | #[existent::nonexistent]
   |             ^^^^^^^^^^^ could not find `nonexistent` in `existent`
```
2026-02-17 16:51:44 +00:00
Stuart Cook 1367126837 Rollup merge of #151783 - mu001999-contrib:impl/final-method, r=fee1-dead
Implement RFC 3678: Final trait methods

Tracking: https://github.com/rust-lang/rust/issues/131179

This PR is based on rust-lang/rust#130802, with some minor changes and conflict resolution.

Futhermore, this PR excludes final methods from the vtable of a dyn Trait.

And some excerpt from the original PR description:
> Implements the surface part of https://github.com/rust-lang/rfcs/pull/3678.
>
> I'm using the word "method" in the title, but in the diagnostics and the feature gate I used "associated function", since that's more accurate.

cc @joshtriplett
2026-02-17 13:02:21 +11:00
Kivooeo 964b63f42e if let guard stabilize 2026-02-16 12:24:15 +00:00
Jacob Pratt 494c6da389 Rollup merge of #150601 - folkertdev:c-variadic-const-eval, r=RalfJung
support c-variadic functions in `rustc_const_eval`

tracking issue: https://github.com/rust-lang/rust/issues/44930

The new `GlobalAlloc::VaList` is used to create an `AllocId` that represents the variable argument list of a frame. The allocation itself does not store any data, all we need is the unique identifier.

The actual variable argument list is stored in `Memory`, and keyed by the `AllocId`. The `Frame` also stores this `AllocId`, so that when a frame is popped, it can deallocate the variable arguments.

At "runtime" a `VaList` value stores a pointer to the global allocation in its first bytes. The provenance on this pointer can be used to retrieve its `AllocId`, and the offset of the pointer is used to store the index of the next argument to read from the variable argument list.

Miri does not yet support `va_arg`, but I think that can be done separetely?

r? @RalfJung
cc @workingjubilee
2026-02-16 04:28:56 -05:00
bors 75b9d89c68 Auto merge of #151380 - ShoyuVanilla:shallow-resolve-to-root-var, r=lcnr
Shallow resolve ty and const vars to their root vars

Continuation of https://github.com/rust-lang/rust/pull/147193
2026-02-15 03:04:28 +00:00
Folkert de Vries f5bf3353e6 move va_list operations into InterpCx 2026-02-14 22:55:26 +01:00
Folkert de Vries ce693807f6 make Va::arg and VaList::drop const fns 2026-02-14 22:26:24 +01:00
Folkert de Vries a7888c1342 allow const fn to be c-variadic
however `Drop` for `VaList` is not yet available in const fn
2026-02-14 22:26:23 +01:00
yukang ba0e1c9497 Address review comments: fix span and add run-rustfix
- Change error span to start from 'const' keyword instead of binop RHS
- Add decl_lo parameter to missing_semi_from_binop() for better spans
- Add run-rustfix directive to test file
- Simplify test to focus on const item recovery cases
2026-02-12 18:49:58 +08:00
yukang 6f40616148 remove mismatched errors when recovered 2026-02-12 18:19:08 +08:00
yukang 6d0e077d13 also add recover from over parsing for let 2026-02-12 18:19:07 +08:00
yukang caf7cdf558 Improve code suggestion for incorrect macro_rules! usage 2026-02-12 15:30:41 +08:00
mu001999 7077797f52 Parse and lower final for methods
Co-authored-by: Michael Goulet <michael@errs.io>
2026-02-12 15:12:29 +08:00
Shoyu Vanilla 8062bee9e3 Bless tests 2026-02-11 18:08:18 +09:00
Stuart Cook 55277add61 Rollup merge of #150443 - estebank:long-diff-markers, r=jackh726
Support long diff conflict markers

git can be configured to use more than 7 characters for conflict markers, and jj automatically uses longer conflict markers when the text contains any char sequence that could be confused with conflict markers. Ensure that we only point at markers that are consistent with the start marker's length.

Ensure that we only consider char sequences at the beginning of a line as a diff marker.

Fix https://github.com/rust-lang/rust/issues/150352.
2026-02-08 16:58:23 +11:00
Jonathan Brouwer 6ff5bb3968 Rollup merge of #151290 - Unique-Usman:ua/nostruct, r=estebank
Recover from struct literals with placeholder or empty path

Based on earlier work by León Orell Valerian Liehr.
2026-01-26 18:19:12 +01:00
Usman Akinyemi 54fc546f20 Recover from struct literals with placeholder or empty path
Based on earlier work by León Orell Valerian Liehr.

Co-authored-by: León Orell Valerian Liehr <me@fmease.dev>
Signed-off-by: Usman Akinyemi <uniqueusman@archlinux>
2026-01-26 04:09:28 +05:30
Pavel Grigorenko d14491567b rustfmt: support const block items 2026-01-23 13:29:24 +03:00
Pavel Grigorenko a315d230d5 const_block_items: do not create an AnonConst 2026-01-21 19:36:27 +03:00
Pavel Grigorenko e77b11924f const_block_items: tests 2026-01-21 19:36:27 +03:00
Pavel Grigorenko 5eb01938c9 Audit AllowConstBlockItems 2026-01-21 19:36:14 +03:00
Jonathan Brouwer 8c5e10bb11 Rollup merge of #151249 - fix/151238, r=petrochenkov
Parse ident with allowing recovery when trying to diagnose

Fixes rust-lang/rust#151238

rust-lang/rust#146978 made parsing ident not always allowed-recovery ([change](https://github.com/rust-lang/rust/pull/146978/changes#diff-ef8d6186dc7fb1d03a71446d0c9e6cc9e72158ec6896703dcf05686ee7dc83fcL469-R469)), so when matching macro with `NoopTracker`, which has `Recovery::Forbidden`, ICE happens when trying to parse kw as ident and then unwraping it.

This PR introduces a new method for parsing ident with allowing recovery when trying to diagnose. Then errors will behave like previous.

r? @petrochenkov
2026-01-19 20:53:24 +01:00
mu001999 3713512217 Parse ident with allowing recovery when trying to recover in diagnosing 2026-01-19 10:08:45 +08:00
Esteban Küber d194795f14 Do not recover from Trait() if generic list is unterminated
If we encounter `fn foo<T: Trait()`, the recovery logic would it as if `Trait` was intended to use the Fn-like trait syntax, but if we don't know for certain that we've parsed a full trait bound (`fn foo<T: Trait()>`), we bail from the recovery as more likely there could have been a missing closing `>` and the `(` corresponds to the start of the fn parameter list.
2026-01-15 19:32:39 +00:00
Jonathan Brouwer 9ef76797ea Rollup merge of #150590 - ident-kw-ice, r=petrochenkov
Don't try to recover keyword as non-keyword identifier

Fixes rust-lang/rust#149692.

On beta after rust-lang/rust#146978, we ICE on

```rs
macro_rules! m {
    ($id:item()) => {}
}

m!(Self());
```

where `Self` in the macro invocation is a keyword not a "normal" identifier, while attempting to recover an missing keyword before an identifier. Except, `Self` *is* a keyword, so trying to parse that as a non-reserved identifier expectedly fails.

I suspect rust-lang/rust#146978 merely unmasked a possible code path to hit this case; this logic has been so for a good while. Previously, on stable, the error message looks something like

```rs
error: expected identifier, found keyword `Self`
 --> src/lib.rs:5:4
  |
5 | m!(Self());
  |    ^^^^ expected identifier, found keyword

error: missing `fn` or `struct` for function or struct definition
 --> src/lib.rs:5:4
  |
2 |     ($id:item()) => {}
  |      -------- while parsing argument for this `item` macro fragment
...
5 | m!(Self());
  |    ^^^^
  |
help: if you meant to call a macro, try
  |
5 | m!(Self!());
  |        +
```

I considered restoring this diagnostic, but I'm not super convinced it's worth the complexity (and to me, it's not super clear what the user actually intended here).
2026-01-14 22:29:56 +01:00
AprilNEA 4421270516 Merge associated_const_equality feature gate into MGCA
This removes `associated_const_equality` as a separate feature gate and makes it part of `min_generic_const_args` (mgca).

Key changes:
  - Remove `associated_const_equality` from unstable features, add to removed
  - Update all test files to use `min_generic_const_args` instead
  - Preserve the original "associated const equality is incomplete" error message by specially handling `sym::associated_const_equality` spans in `feature_gate.rs`
  - Rename FIXME(associated_const_equality) to FIXME(mgca)
2026-01-05 12:31:42 +08:00
Esteban Küber ebd4bc9224 Support long diff conflict markers
git can be configured to use more than 7 characters for conflict markers, and jj automatically uses longer conflict markers when the text contains any char sequence that could be confused with conflict markers. Ensure that we only point at markers that are consistent with the start marker's length.

Ensure that we only consider char sequences at the beginning of a line as a diff marker.
2026-01-02 22:32:52 +00:00
Jieyou Xu 31531b3665 Add regression tests for keyword-in-identifier-position recovery ICE
... in macro invocations.

Issue: <https://github.com/rust-lang/rust/issues/149692>.
2026-01-02 17:26:41 +08:00
Jonathan Brouwer 21d3df6268 Rollup merge of #150382 - estebank:git-markers-wording, r=nnethercote
Tweak wording of diff marker diagnostic
2026-01-02 00:04:07 +01:00
Esteban Küber 40be1f8bc5 Tweak wording of diff marker diagnostic 2025-12-25 20:56:03 +00:00
Matthias Krüger b6c2dab72b Rollup merge of #150216 - reddevilmidzy:t13, r=Kivooeo
Tidying up tests/ui/issues 15 tests [6/N]

> [!NOTE]
> Intermediate commits are intended to help review, but will be squashed add comment commit prior to merge.

part of rust-lang/rust#133895

r? Kivooeo
2025-12-24 00:54:36 +01:00
reddevilmidzy 4578082361 Cleaned up some tests
add comment to closure-move-use-after-move-diagnostic.rs

add comment to missing-operator-after-float.rs

add comment to closure-array-break-length.rs

add comment to box-lifetime-argument-not-allowed.rs

add comment to const-return-outside-fn.rs

add comment to drop-conflicting-impls.rs

add comment to unbalanced-doublequote-2.rs

add comment to borrow-immutable-deref-box.rs

add comment to for-in-const-eval.rs

add comment to borrowck-annotated-static-lifetime.rs

cleaned up cast-rfc0401.rs

add comment to nll-anon-to-static.rs

add comment to cast-to-dyn-any.rs

add comment to missing-associated-items.rs

add comment to enum-discriminant-missing-variant.rs
2025-12-23 21:13:24 +09:00
reddevilmidzy 7ca2eb9c6f moved test 2025-12-23 20:33:37 +09:00