Point at lint name instead of whole attr for gated lints
```
warning: unknown lint: `test_unstable_lint`
--> $DIR/warn-unknown-unstable-lint-inline.rs:4:10
|
LL | #![allow(test_unstable_lint, another_unstable_lint)]
| ^^^^^^^^^^^^^^^^^^
|
= note: the `test_unstable_lint` lint is unstable
= help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
note: the lint level is defined here
--> $DIR/warn-unknown-unstable-lint-inline.rs:3:9
|
LL | #![warn(unknown_lints)]
| ^^^^^^^^^^^^^
warning: unknown lint: `test_unstable_lint`
--> $DIR/warn-unknown-unstable-lint-inline.rs:4:29
|
LL | #![allow(test_unstable_lint, another_unstable_lint)]
| ^^^^^^^^^^^^^^^^^^^^^
|
= note: the `another_unstable_lint` lint is unstable
= help: add `#![feature(another_unstable_lint)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
```
This is particularly relevant when there are multiple lints in the same `warn` attribute. Pointing at the smaller span makes it clearer which one the warning is complaining about.
Advent of `tests/ui` (misc cleanups and improvements) [3/N]
Part of #133895.
Misc improvements to some ui tests immediately under `tests/ui/`.
Best reviewed commit-by-commit. Each commit's commit message contains further elaboration and rationale for changes.
r? compiler
Update books
## rust-lang/book
21 commits in 9900d976bbfecf4e8124da54351a9ad85ee3c7f3..ad2011d3bcad9f152d034faf7635c22506839d58
2024-12-16 16:11:34 UTC to 2024-12-05 19:19:24 UTC
- Ch. 10: clarify note about compiler errors and `'static` (rust-lang/book#4164)
- Introduce `let`-`else` statement (rust-lang/book#3702)
- Fix misleading explanation of comma in `$(),*` (rust-lang/book#3800)
- ch18-03: Matching Named Variables: mention `if let`/`while let` (rust-lang/book#3110)
- Ch. 4: Rephrase/clarify paragraph on reference scope (rust-lang/book#3688)
- Simplify note about functions in ch13-01-closures.md (rust-lang/book#3699)
- fix: make the reason more understandable (rust-lang/book#4074)
- Fixed grammatical error in the comment on line 22 (rust-lang/book#3180)
- ch17-02: Monomorphization applies to generics in general (rust-lang/book#3367)
- Ch. 21: Use `Vec::drain` to teach alternatives to `Option` (rust-lang/book#4159)
- fix(typo): correct punctuation in ch15-06-reference-cycles.md (rust-lang/book#4155)
- Ch. 20: show both `impl Fn` and `Box<dyn Fn>` (rust-lang/book#4152)
- Add `use super::*;` to unit-test examples. (rust-lang/book#4151)
- Remove emphasis on four-space indents (rust-lang/book#4150)
- Fix `.git-blame-ignore-revs` file (rust-lang/book#4149)
- Rust 2024: distinguish `unsafe fn` vs. `unsafe` blocks (rust-lang/book#4148)
- Update README.md typo (rust-lang/book#4146)
- Ch. 15.5: account for improved error message (rust-lang/book#4142)
- Document use of rustfmt and dprint for formatting (rust-lang/book#4138)
- tools: fix nostarch build reference to mdbook-trpl (rust-lang/book#4137)
- Revise sentence to not refer to two subjects as it (rust-lang/book#4136)
## edition-guide
6 commits in 128669297c8a7fdf771042eaec18b8adfaeaf0cd..bc4ce51e1d4dacb9350a92e95f6159a42de2f8c6
2024-12-03 22:02:43 +0000 to 2024-12-18 05:34:59 +0000
- Add chapter for 2024 match ergonomics reservations (rust-lang/edition-guide#349)
- Re-title "Additions to the prelude" (rust-lang/edition-guide#348)
- Show tail expression temporary example that fails in 2024 (rust-lang/edition-guide#345)
- Add more triagebot labeling support (rust-lang/edition-guide#346)
- 2024: Assignment operator RHS indentation (rust-lang/edition-guide#341)
- 2024: Add chapter on single-line `where` clauses (rust-lang/edition-guide#340)
## rust-lang/nomicon
1 commits in 0674321898cd454764ab69702819d39a919afd68..97e84a38c94bf9362b11284c20b2cb4adaa1e868
2024-12-10 02:41:27 UTC to 2024-12-10 02:41:27 UTC
- races.md: data race -> race condition to violate memory safety (rust-lang/nomicon#470)
## reference
8 commits in ede56d1bbe132bac476b5029cd6d7508ca9572e9..9f41bc11342d46544ae0732caf14ec0bcaf27376
2024-12-03 22:26:55 +0000 to 2024-12-18 23:04:30 +0000
- `coverage` attribute (rust-lang/reference#1628)
- Clarify that `extern crate foo as føø` is allowed (rust-lang/reference#1697)
- Fix rule auto-linking on Windows (rust-lang/reference#1698)
- Reflect rust#133422 & rust#133587 to inline assembly documentation (rust-lang/reference#1695)
- Describe async closures (rust-lang/reference#1692)
- Update closures for edition 2021 disjoint closure capturing (rust-lang/reference#1521)
- Fix paragraphs with trailing `\1` (rust-lang/reference#1696)
- Add triagebot autolabel (rust-lang/reference#1694)
## rust-lang/rust-by-example
1 commits in e1d1f2cdcee4d52b9a01ff7c448be4372a377b70..76406337f4131253443aea0ed7e7f451b464117c
2024-12-07 00:24:30 UTC to 2024-12-07 00:24:30 UTC
- Fix#1900 (rust-lang/rust-by-example#1901)
## rust-lang/rustc-dev-guide
9 commits in b21d99b770f9aceb0810c843847c52f86f45d2ed..7f7ba48f04abc2ad25e52f30b5e2bffa286b019f
2024-12-16 07:12:01 UTC to 2024-12-05 05:01:46 UTC
- Specify what a CGU is (rust-lang/rustc-dev-guide#2163)
- functionality removed from codebase (part 2) (rust-lang/rustc-dev-guide#2160)
- functionality removed from codebase (rust-lang/rustc-dev-guide#2159)
- remove polymorphization (rust-lang/rustc-dev-guide#2158)
- squashing: recommend --keep-base when squashing without a conflict (rust-lang/rustc-dev-guide#2157)
- update section even more (rust-lang/rustc-dev-guide#2156)
- extend closure constraints section (rust-lang/rustc-dev-guide#2155)
- Remove `//@ compare-output-lines-by-subset` directive (rust-lang/rustc-dev-guide#2151)
- Document `needs-target-has-atomic` directive (rust-lang/rustc-dev-guide#2154)
-Znext-solver: modify candidate preference rules
This implements the design proposed in the FCP in #132325 and matches the old solver behavior. I hope the inline comments are all sufficiently clear, I personally think this is a fairly clear improvement over the existing approach using `fn discard_impls_shadowed_by_env`. This fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/96.
This also fixes#133639 which encounters an ICE in negative coherence when evaluating the where-clause. Given the features required to trigger this ICE 🤷
r? ``@compiler-errors``
Stabilize `#[diagnostic::do_not_recommend]`
This PR seeks to stabilize the `#[diagnostic::do_not_recommend]`attribute.
This attribute was first proposed as `#[do_not_recommend`] attribute in RFC 2397 (https://github.com/rust-lang/rfcs/pull/2397). It gives the crate authors the ability to not suggest to the compiler to not show certain traits in its error messages.
With the presence of the `#[diagnostic]` tool attribute namespace it was decided to move the attribute there, as that lowers the amount of guarantees the compiler needs to give about the exact way this influences error messages. It turns the attribute into a hint which can be ignored. In addition to the original proposed functionality this attribute now also hides the marked trait in help messages ("This trait is implemented by: ").
The attribute does not accept any argument and can only be placed on trait implementations. If it is placed somewhere else a lint warning is emitted and the attribute is otherwise ignored. If an argument is detected a lint warning is emitted and the argument is ignored. This follows the rules outlined by the diagnostic namespace.
This attribute allows crates like diesel to improve their error messages drastically. The most common example here is the following error message:
```
error[E0277]: the trait bound `&str: Expression` is not satisfied
--> /home/weiznich/Documents/rust/rust/tests/ui/diagnostic_namespace/do_not_recommend.rs:53:15
|
LL | SelectInt.check("bar");
| ^^^^^ the trait `Expression` is not implemented for `&str`, which is required by `&str: AsExpression<Integer>`
|
= help: the following other types implement trait `Expression`:
Bound<T>
SelectInt
note: required for `&str` to implement `AsExpression<Integer>`
--> /home/weiznich/Documents/rust/rust/tests/ui/diagnostic_namespace/do_not_recommend.rs:26:13
|
LL | impl<T, ST> AsExpression<ST> for T
| ^^^^^^^^^^^^^^^^ ^
LL | where
LL | T: Expression<SqlType = ST>,
| ------------------------ unsatisfied trait bound introduced here
```
By applying the new attribute to the wild card trait implementation of
`AsExpression` for `T: Expression` the error message becomes:
```
error[E0277]: the trait bound `&str: AsExpression<Integer>` is not satisfied
--> $DIR/as_expression.rs:55:15
|
LL | SelectInt.check("bar");
| ^^^^^ the trait `AsExpression<Integer>` is not implemented for `&str`
|
= help: the trait `AsExpression<Text>` is implemented for `&str`
= help: for that trait implementation, expected `Text`, found `Integer`
```
which makes it much easier for users to understand that they are facing a type mismatch.
Other explored example usages include:
* This standard library error message: https://github.com/rust-lang/rust/pull/128008
* That bevy derived example:
e1f3068995/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.rs (No
more tuple pyramids)
Fixes#51992
r? ``@compiler-errors``
This PR also adds a few more tests, makes sure that all the tests are run for the old and new trait solver and adds a check that the attribute does not contain arguments.
```
warning: unknown lint: `test_unstable_lint`
--> $DIR/warn-unknown-unstable-lint-inline.rs:4:10
|
LL | #![allow(test_unstable_lint, another_unstable_lint)]
| ^^^^^^^^^^^^^^^^^^
|
= note: the `test_unstable_lint` lint is unstable
= help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
note: the lint level is defined here
--> $DIR/warn-unknown-unstable-lint-inline.rs:3:9
|
LL | #![warn(unknown_lints)]
| ^^^^^^^^^^^^^
warning: unknown lint: `test_unstable_lint`
--> $DIR/warn-unknown-unstable-lint-inline.rs:4:29
|
LL | #![allow(test_unstable_lint, another_unstable_lint)]
| ^^^^^^^^^^^^^^^^^^^^^
|
= note: the `test_unstable_lint` lint is unstable
= help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
note: the lint level is defined here
--> $DIR/warn-unknown-unstable-lint-inline.rs:3:9
|
LL | #![warn(unknown_lints)]
| ^^^^^^^^^^^^^
```
This is particularly relevant when there are multiple lints in the same `warn` attribute. Pointing at the smaller span makes it clearer which one the warning is complaining about.
Use field init shorthand where possible
Field init shorthand allows writing initializers like `tcx: tcx` as
`tcx`. The compiler already uses it extensively. Fix the last few places
where it isn't yet used.
EDIT: this PR also updates `rustfmt.toml` to set
`use_field_init_shorthand = true`.
Rollup of 11 pull requests
Successful merges:
- #130786 ( mir-opt: a sub-BB of a cleanup BB must also be a cleanup BB in `EarlyOtherwiseBranch`)
- #133926 (Fix const conditions for RPITITs)
- #134161 (Overhaul token cursors)
- #134253 (Overhaul keyword handling)
- #134394 (Clarify the match ergonomics 2024 migration lint's output)
- #134399 (Do not do if ! else, use unnegated cond and swap the branches instead)
- #134420 (refactor: replace &PathBuf with &Path to enhance generality)
- #134436 (tests/assembly/asm: Remove uses of rustc_attrs and lang_items features by using minicore)
- #134444 (Fix `x build --stage 1 std` when using cg_cranelift as the default backend)
- #134452 (fix(LazyCell): documentation of get[_mut] was wrong)
- #134460 (Merge some patterns together)
r? `@ghost`
`@rustbot` modify labels: rollup
Merge some patterns together
just something I noticed while browsing code. No change in functionality, deduplicates the 100% equal match arms by creating one big or pattern
fix(LazyCell): documentation of get[_mut] was wrong
- `LazyCell::get`: said it was returning a **mutable** reference.
- `LazyCell::get_mut`: said it was returning a reference (the mutable was missing).
Related to #129333 (`lazy_get`). `LazyLock`'s documentation was correct.
Fix `x build --stage 1 std` when using cg_cranelift as the default backend
Before, cg_cranelift would ICE when trying to lower f16 and f128. The library/ crates had all the infrastructure to omit using them, it just wasn't hooked up to bootstrap.
r? `````@bjorn3`````
tests/assembly/asm: Remove uses of rustc_attrs and lang_items features by using minicore
Similar to https://github.com/rust-lang/rust/pull/134385 (for tests/ui/asm), but for tests/assembly/asm.
r? jieyouxu
Do not do if ! else, use unnegated cond and swap the branches instead
I'm tidying up my ergonomic ref counting PR and I'm going to make some small, simple and unrelated changes outside that PR, so the main PR sticks more straight to the point.
Clarify the match ergonomics 2024 migration lint's output
This makes a few changes:
- Rather than using the whole pattern as a span for the lint, this collects spans for each problematic default binding mode reset and labels them with why they're problems.
- The lint's suggestions are now verbose-styled, so that it's clear what's being suggested vs. what's problematic.
- The wording is now less technical, and the hard error version of this diagnostic now links to the same reference material as the lint (currently an unwritten page of the edition guide).
I'm not totally confident in the wording or formatting, so I'd appreciate feedback on that in particular. I tried to draw a connection with word choice between the labels and the suggestion, but it might be imprecise, unclear, or cluttered. If so, it might be worth making the labels more terse and adding notes that explain them, but that's harder to read in a way too.
cc ```@Nadrieril``` ```@Jules-Bertholet```
Closes#133854. For reference, the error from that issue becomes:
```
error: pattern uses features incompatible with edition 2024
--> $DIR/remove-me.rs:6:25
|
LL | map.iter().filter(|(&(_x, _y), &_c)| false);
| ^ ^ cannot implicitly match against multiple layers of reference
| |
| cannot implicitly match against multiple layers of reference
|
help: make the implied reference pattern explicit
|
LL | map.iter().filter(|&(&(_x, _y), &_c)| false);
| +
```
Overhaul keyword handling
The compiler's list of keywords has some problems.
- It contains several items that aren't keywords.
- The order isn't quite right in a couple of places.
- Some of the names of predicates relating to keywords are confusing.
- rustdoc and rustfmt have their own (incorrect) versions of the keyword list.
- `AllKeywords` is unnecessarily complex.
r? ```@jieyouxu```
`gen` is an edition-specific keyword used in unstable Rust, and so
belongs with `try` (as `is_unused_keyword_conditional` indicates).
Also, the cases in `is_unused_keyword_conditional` should be in
alphabetical order, to match the keyword list.
These changes don't affect the behaviour of any of the `Symbol::is_*`
functions.
`rustc_symbol` is the source of truth for keywords.
rustdoc has its own implicit definition of keywords, via the
`is_doc_keyword`. It (presumably) intends to include all keywords, but
it omits `yeet`.
rustfmt has its own explicit list of Rust keywords. It also (presumably)
intends to include all keywords, but it omits `await`, `builtin`, `gen`,
`macro_rules`, `raw`, `reuse`, `safe`, and `yeet`. Also, it does linear
searches through this list, which is inefficient.
This commit fixes all of the above problems by introducing a new
predicate `is_any_keyword` in rustc and using it in rustdoc and rustfmt.
It documents that it's not the right predicate in most cases.
This commit seeks to stabilize the `#[diagnostic::do_not_recommend]`
attribute.
This attribute was first proposed as `#[do_not_recommend`] attribute in
RFC 2397 (https://github.com/rust-lang/rfcs/pull/2397). It gives the
crate authors the ability to not suggest to the compiler to not show
certain traits in it's error messages. With the presence of the
`#[diagnostic]` tool attribute namespace it was decided to move the
attribute there, as that lowers the amount of guarantees the compiler
needs to give about the exact way this influences error messages. It
turns the attribute into a hint which can be ignored. In addition to the
original proposed functionality this attribute now also hides the marked
trait in help messages ("This trait is implemented by: ").
The attribute does not accept any argument and can only be placed on
trait implementations. If it is placed somewhere else a lint warning is
emitted and the attribute is otherwise ignored. If an argument is
detected a lint warning is emitted and the argument is ignored. This
follows the rules outlined by the diagnostic namespace.
This attribute allows crates like diesel to improve their error messages
drastically. The most common example here is the following error
message:
```
error[E0277]: the trait bound `&str: Expression` is not satisfied
--> /home/weiznich/Documents/rust/rust/tests/ui/diagnostic_namespace/do_not_recommend.rs:53:15
|
LL | SelectInt.check("bar");
| ^^^^^ the trait `Expression` is not implemented for `&str`, which is required by `&str: AsExpression<Integer>`
|
= help: the following other types implement trait `Expression`:
Bound<T>
SelectInt
note: required for `&str` to implement `AsExpression<Integer>`
--> /home/weiznich/Documents/rust/rust/tests/ui/diagnostic_namespace/do_not_recommend.rs:26:13
|
LL | impl<T, ST> AsExpression<ST> for T
| ^^^^^^^^^^^^^^^^ ^
LL | where
LL | T: Expression<SqlType = ST>,
| ------------------------ unsatisfied trait bound introduced here
```
By applying the new attribute to the wild card trait implementation of
`AsExpression` for `T: Expression` the error message becomes:
```
error[E0277]: the trait bound `&str: AsExpression<Integer>` is not satisfied
--> $DIR/as_expression.rs:55:15
|
LL | SelectInt.check("bar");
| ^^^^^ the trait `AsExpression<Integer>` is not implemented for `&str`
|
= help: the trait `AsExpression<Text>` is implemented for `&str`
= help: for that trait implementation, expected `Text`, found `Integer`
```
which makes it much easier for users to understand that they are facing
a type mismatch.
Other explored example usages included
* This standard library error message: https://github.com/rust-lang/rust/pull/128008
* That bevy derived example:
e1f3068995/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.rs (No
more tuple pyramids)
Fixes#51992
This PR aims to improve the testing coverage for
`#[diagnostic::do_not_recommend]`. It ensures that all tests are run for
the old and new solver to verify that the behaviour is the same for both
variants. It also adds two new tests:
* A test with 4 traits having wild card impl for each other, with
alternating `#[diagnostic::do_not_recommend]` attributse
* A test with a lifetime dependend wild card impl, which is something
that's not supported yet
Update cargo
6 commits in 769f622e12db0001431d8ae36d1093fb8727c5d9..99dff6d77db779716dda9ca3b29c26addd02c1be
2024-12-14 04:27:35 +0000 to 2024-12-18 00:55:17 +0000
- fix(build-std): make Resolve align to what to build (rust-lang/cargo#14938)
- test(build-std): Isolate output test to avoid spurious `[BLOCKING]` messages from concurrent runs (rust-lang/cargo#14943)
- docs: fix wrong changelog PR link (rust-lang/cargo#14947)
- docs(unstable): Correct stabilization version for MSRV-resolver (rust-lang/cargo#14945)
- Update release information for home 0.5.11 (rust-lang/cargo#14939)
- Limit release trigger to 0.* tags (rust-lang/cargo#14940)
Re-export more `rustc_span::symbol` things from `rustc_span`.
`rustc_span::symbol` defines some things that are re-exported from `rustc_span`, such as `Symbol` and `sym`. But it doesn't re-export some closely related things such as `Ident` and `kw`. So you can do `use rustc_span::{Symbol, sym}` but you have to do `use rustc_span::symbol::{Ident, kw}`, which is inconsistent for no good reason.
This commit re-exports `Ident`, `kw`, and `MacroRulesNormalizedIdent`, and changes many `rustc_span::symbol::` qualifiers to `rustc_span::`. This is a 300+ net line of code reduction, mostly because many files with two `use rustc_span` items can be reduced to one.
r? `@jieyouxu`
`rustc_span::symbol` defines some things that are re-exported from
`rustc_span`, such as `Symbol` and `sym`. But it doesn't re-export some
closely related things such as `Ident` and `kw`. So you can do `use
rustc_span::{Symbol, sym}` but you have to do `use
rustc_span::symbol::{Ident, kw}`, which is inconsistent for no good
reason.
This commit re-exports `Ident`, `kw`, and `MacroRulesNormalizedIdent`,
and changes many `rustc_span::symbol::` qualifiers in `compiler/` to
`rustc_span::`. This is a 200+ net line of code reduction, mostly
because many files with two `use rustc_span` items can be reduced to
one.
