Commit Graph

9319 Commits

Author SHA1 Message Date
Joshua Nelson 345c42a2d6 Stabilize `#![feature(label_break_value)]`
# Stabilization proposal

The feature was implemented in https://github.com/rust-lang/rust/pull/50045 by est31 and has been in nightly since 2018-05-16 (over 4 years now).
There are [no open issues][issue-label] other than the tracking issue. There is a strong consensus that `break` is the right keyword and we should not use `return`.

There have been several concerns raised about this feature on the tracking issue (other than the one about tests, which has been fixed, and an interaction with try blocks, which has been fixed).
1. nrc's original comment about cost-benefit analysis: https://github.com/rust-lang/rust/issues/48594#issuecomment-422235234
2. joshtriplett's comments about seeing use cases: https://github.com/rust-lang/rust/issues/48594#issuecomment-422281176
3. withoutboats's comments that Rust does not need more control flow constructs: https://github.com/rust-lang/rust/issues/48594#issuecomment-450050630

Many different examples of code that's simpler using this feature have been provided:
- A lexer by rpjohnst which must repeat code without label-break-value: https://github.com/rust-lang/rust/issues/48594#issuecomment-422502014
- A snippet by SergioBenitez which avoids using a new function and adding several new return points to a function: https://github.com/rust-lang/rust/issues/48594#issuecomment-427628251. This particular case would also work if `try` blocks were stabilized (at the cost of making the code harder to optimize).
- Several examples by JohnBSmith: https://github.com/rust-lang/rust/issues/48594#issuecomment-434651395
- Several examples by Centril: https://github.com/rust-lang/rust/issues/48594#issuecomment-440154733
- An example by petrochenkov where this is used in the compiler itself to avoid duplicating error checking code: https://github.com/rust-lang/rust/issues/48594#issuecomment-443557569
- Amanieu recently provided another example related to complex conditions, where try blocks would not have helped: https://github.com/rust-lang/rust/issues/48594#issuecomment-1184213006

Additionally, petrochenkov notes that this is strictly more powerful than labelled loops due to macros which accidentally exit a loop instead of being consumed by the macro matchers: https://github.com/rust-lang/rust/issues/48594#issuecomment-450246249

nrc later resolved their concern, mostly because of the aforementioned macro problems.
joshtriplett suggested that macros could be able to generate IR directly
(https://github.com/rust-lang/rust/issues/48594#issuecomment-451685983) but there are no open RFCs,
and the design space seems rather speculative.

joshtriplett later resolved his concerns, due to a symmetry between this feature and existing labelled break: https://github.com/rust-lang/rust/issues/48594#issuecomment-632960804

withoutboats has regrettably left the language team.

joshtriplett later posted that the lang team would consider starting an FCP given a stabilization report: https://github.com/rust-lang/rust/issues/48594#issuecomment-1111269353

[issue-label]: https://github.com/rust-lang/rust/issues?q=is%3Aissue+is%3Aopen+label%3AF-label_break_value+

 ## Report

+ Feature gate:
    - d695a497bb/src/test/ui/feature-gates/feature-gate-label_break_value.rs
+ Diagnostics:
    - 6b2d3d5f3c/compiler/rustc_parse/src/parser/diagnostics.rs (L2629)
    - f65bf0b2bb/compiler/rustc_resolve/src/diagnostics.rs (L749)
    - f65bf0b2bb/compiler/rustc_resolve/src/diagnostics.rs (L1001)
    - 111df9e6ed/compiler/rustc_passes/src/loops.rs (L254)
    - d695a497bb/compiler/rustc_parse/src/parser/expr.rs (L2079)
    - d695a497bb/compiler/rustc_parse/src/parser/expr.rs (L1569)
+ Tests:
    - https://github.com/rust-lang/rust/blob/master/src/test/ui/label/label_break_value_continue.rs
    - https://github.com/rust-lang/rust/blob/master/src/test/ui/label/label_break_value_unlabeled_break.rs
    - https://github.com/rust-lang/rust/blob/master/src/test/ui/label/label_break_value_illegal_uses.rs
    - https://github.com/rust-lang/rust/blob/master/src/test/ui/lint/unused_labels.rs
    - https://github.com/rust-lang/rust/blob/master/src/test/ui/run-pass/for-loop-while/label_break_value.rs

 ## Interactions with other features

Labels follow the hygiene of local variables.

label-break-value is permitted within `try` blocks:
```rust
let _: Result<(), ()> = try {
    'foo: {
        Err(())?;
        break 'foo;
    }
};
```

label-break-value is disallowed within closures, generators, and async blocks:
```rust
'a: {
    || break 'a
    //~^ ERROR use of unreachable label `'a`
    //~| ERROR `break` inside of a closure
}
```

label-break-value is disallowed on [_BlockExpression_]; it can only occur as a [_LoopExpression_]:
```rust
fn labeled_match() {
    match false 'b: { //~ ERROR block label not supported here
        _ => {}
    }
}

macro_rules! m {
    ($b:block) => {
        'lab: $b; //~ ERROR cannot use a `block` macro fragment here
        unsafe $b; //~ ERROR cannot use a `block` macro fragment here
        |x: u8| -> () $b; //~ ERROR cannot use a `block` macro fragment here
    }
}

fn foo() {
    m!({});
}
```

[_BlockExpression_]: https://doc.rust-lang.org/nightly/reference/expressions/block-expr.html
[_LoopExpression_]: https://doc.rust-lang.org/nightly/reference/expressions/loop-expr.html
2022-08-23 21:14:12 -05:00
Matthias Krüger 37eeed701a Rollup merge of #100018 - nnethercote:clean-up-LitKind, r=petrochenkov
Clean up `LitKind`

r? ``@petrochenkov``
2022-08-17 12:32:49 +02:00
Nicholas Nethercote e92183c286 Rename some things related to literals.
- Rename `ast::Lit::token` as `ast::Lit::token_lit`, because its type is
  `token::Lit`, which is not a token. (This has been confusing me for a
  long time.)
  reasonable because we have an `ast::token::Lit` inside an `ast::Lit`.
- Rename `LitKind::{from,to}_lit_token` as
  `LitKind::{from,to}_token_lit`, to match the above change and
  `token::Lit`.
2022-08-16 13:41:34 +10:00
Nicholas Nethercote 6e5f90ae46 Shrink `ast::Attribute`. 2022-08-16 11:10:13 +10:00
bors 86a0a18179 Auto merge of #96745 - ehuss:even-more-attribute-validation, r=cjgillot
Visit attributes in more places.

This adds 3 loosely related changes (I can split PRs if desired):

- Attribute checking on pattern struct fields.
- Attribute checking on struct expression fields.
- Lint level visiting on pattern struct fields, struct expression fields, and generic parameters.

There are still some lints which ignore lint levels in various positions. This is a consequence of how the lints themselves are implemented. For example, lint levels on associated consts don't work with `unused_braces`.
2022-08-15 05:50:54 +00:00
Mark Rousskov 1a3192a331 Adjust cfgs 2022-08-12 16:28:15 -04:00
Eric Huss 3c4aec500f Update clippy for introduction of Node::ExprField 2022-08-11 21:56:33 -07:00
bors 9ac237dce5 Auto merge of #100419 - flip1995:clippyup, r=Manishearth
Update Clippy

r? `@Manishearth`
2022-08-12 00:12:51 +00:00
Matthias Krüger 4d8b6d4f24 Rollup merge of #100392 - nnethercote:simplify-visitors, r=cjgillot
Simplify visitors

By removing some unused arguments.

r? `@cjgillot`
2022-08-11 22:53:08 +02:00
Philipp Krones dc29cfb8d5 Merge commit '2b2190cb5667cdd276a24ef8b9f3692209c54a89' into clippyup 2022-08-11 19:42:16 +02:00
Nicholas Nethercote eb688958d3 Simplify `rustc_ast::visit::Visitor::visit_poly_trait_ref`.
It is passed an argument that is never used.
2022-08-11 11:10:01 +10:00
Camille GILLOT cf3f71d2a2 Do not consider method call receiver as an argument in AST. 2022-08-10 18:34:54 +02:00
bors f719599c0f Auto merge of #99743 - compiler-errors:fulfillment-context-cleanups, r=jackh726
Some `FulfillmentContext`-related cleanups

Use `ObligationCtxt` in some places, remove some `FulfillmentContext`s in others...

r? types
2022-08-06 06:48:15 +00:00
Michael Goulet ccbc96508a Add `traits::fully_solve_obligation` that acts like `traits::fully_normalize`
It spawns up a trait engine, registers the single obligation, then fully
solves it
2022-08-04 13:50:56 +00:00
Fabian Wolff f232402057 Warn about dead tuple struct fields 2022-08-03 12:17:23 +02:00
Matthias Krüger 7aaeee734f Rollup merge of #100053 - flip1995:clippy_backport, r=xFrednet
move [`assertions_on_result_states`] to restriction

"Backports" the first commit of https://github.com/rust-lang/rust-clippy/pull/9273, so that the lint doesn't go into beta as a warn-by-default lint.

The other changes in the linked PR can ride the train as usual.

r? ``@xFrednet`` (only Clippy changes, so we don't need to bother compiler people)

---

For Clippy:

changelog: none
2022-08-02 17:17:36 +02:00
Matthias Krüger 4546f5d1dc Rollup merge of #99987 - Alexendoo:parse-format-position-span, r=fee1-dead
Always include a position span in `rustc_parse_format::Argument`

Moves the spans from the `Position` enum to always be included in the `Argument` struct. Doesn't make any changes to use it in rustc, but it will be useful for some upcoming Clippy lints
2022-08-02 17:17:30 +02:00
tabokie 2fcaac79bc move [`assertions_on_result_states`] to restriction
Signed-off-by: tabokie <xy.tao@outlook.com>
2022-08-02 10:13:51 +02:00
Camille GILLOT 119247ad32 Remove DefId from AssocItemContainer. 2022-08-01 21:38:45 +02:00
Camille GILLOT d17a30a05d Store associated item defaultness in impl_defaultness. 2022-08-01 21:38:16 +02:00
bors 80a56878cf Auto merge of #99884 - nnethercote:lexer-improvements, r=matklad
Lexer improvements

Some cleanups and small speed improvements.

r? `@matklad`
2022-08-01 12:52:49 +00:00
Nicholas Nethercote 09f9acea0a Shrink `Token`.
From 72 bytes to 12 bytes (on x86-64).

There are two parts to this:
- Changing various source code offsets from 64-bit to 32-bit. This is
  not a problem because the rest of rustc also uses 32-bit source code
  offsets. This means `Token` is no longer `Copy` but this causes no
  problems.
- Removing the `RawStrError` from `LiteralKind`. Raw string literal
  invalidity is now indicated by a `None` value within
  `RawStr`/`RawByteStr`, and the new `validate_raw_str` function can be
  used to re-lex an invalid raw string literal to get the `RawStrError`.

There is one very small change in behaviour. Previously, if a raw string
literal matched both the `InvalidStarter` and `TooManyHashes` cases,
the latter would override the former. This has now changed, because
`raw_double_quoted_string` now uses `?` and so returns immediately upon
detecting the `InvalidStarter` case. I think this is a slight
improvement to report the earlier-detected error, and it explains the
change in the `test_too_many_hashes` test.

The commit also removes a couple of comments that refer to #77629 and
say that the size of these types don't affect performance. These
comments are wrong, though the performance effect is small.
2022-08-01 08:53:04 +10:00
Alex Macleod cd13574992 Always include a position span in rustc_parse_format::Argument 2022-07-31 15:11:33 +00:00
Dylan DPC 72649cf2a6 Rollup merge of #99186 - camsteffen:closure-localdefid, r=cjgillot
Use LocalDefId for closures more
2022-07-31 17:36:40 +05:30
Cameron Steffen 62907727af Use LocalDefId for closures more 2022-07-30 15:59:17 -05:00
bors 3641b0ca30 Auto merge of #99948 - Dylan-DPC:rollup-ed5136t, r=Dylan-DPC
Rollup of 5 pull requests

Successful merges:

 - #99311 (change maybe_body_owned_by to take local def id)
 - #99862 (Improve type mismatch w/ function signatures)
 - #99895 (don't call type ascription "cast")
 - #99900 (remove some manual hash stable impls)
 - #99903 (Add diagnostic when using public instead of pub)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-07-30 17:30:50 +00:00
bors ab7e555ad9 Auto merge of #99887 - nnethercote:rm-TreeAndSpacing, r=petrochenkov
Remove `TreeAndSpacing`.

A `TokenStream` contains a `Lrc<Vec<(TokenTree, Spacing)>>`. But this is
not quite right. `Spacing` makes sense for `TokenTree::Token`, but does
not make sense for `TokenTree::Delimited`, because a
`TokenTree::Delimited` cannot be joined with another `TokenTree`.

This commit fixes this problem, by adding `Spacing` to `TokenTree::Token`,
changing `TokenStream` to contain a `Lrc<Vec<TokenTree>>`, and removing the
`TreeAndSpacing` typedef.

The commit removes these two impls:
- `impl From<TokenTree> for TokenStream`
- `impl From<TokenTree> for TreeAndSpacing`

These were useful, but also resulted in code with many `.into()` calls
that was hard to read, particularly for anyone not highly familiar with
the relevant types. This commit makes some other changes to compensate:
- `TokenTree::token()` becomes `TokenTree::token_{alone,joint}()`.
- `TokenStream::token_{alone,joint}()` are added.
- `TokenStream::delimited` is added.

This results in things like this:
```rust
TokenTree::token(token::Semi, stmt.span).into()
```
changing to this:
```rust
TokenStream::token_alone(token::Semi, stmt.span)
```
This makes the type of the result, and its spacing, clearer.

These changes also simplifies `Cursor` and `CursorRef`, because they no longer
need to distinguish between `next` and `next_with_spacing`.

r? `@petrochenkov`
2022-07-30 14:50:05 +00:00
Miguel Guarniz 6c1110ef5b Avoid ICE when fetching LocalDefId
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
2022-07-29 18:26:10 -04:00
Miguel Guarniz ce5fa10cce Change enclosing_body_owner to return LocalDefId
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
2022-07-29 18:26:10 -04:00
Miguel Guarniz 29a0f69f9c Rename local_did to def_id
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
2022-07-29 18:26:10 -04:00
Miguel Guarniz ca0996e3a0 Change maybe_body_owned_by to take local def id
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
2022-07-29 18:25:58 -04:00
Nicholas Nethercote 1a6f02b1f2 Remove `TreeAndSpacing`.
A `TokenStream` contains a `Lrc<Vec<(TokenTree, Spacing)>>`. But this is
not quite right. `Spacing` makes sense for `TokenTree::Token`, but does
not make sense for `TokenTree::Delimited`, because a
`TokenTree::Delimited` cannot be joined with another `TokenTree`.

This commit fixes this problem, by adding `Spacing` to `TokenTree::Token`,
changing `TokenStream` to contain a `Lrc<Vec<TokenTree>>`, and removing the
`TreeAndSpacing` typedef.

The commit removes these two impls:
- `impl From<TokenTree> for TokenStream`
- `impl From<TokenTree> for TreeAndSpacing`

These were useful, but also resulted in code with many `.into()` calls
that was hard to read, particularly for anyone not highly familiar with
the relevant types. This commit makes some other changes to compensate:
- `TokenTree::token()` becomes `TokenTree::token_{alone,joint}()`.
- `TokenStream::token_{alone,joint}()` are added.
- `TokenStream::delimited` is added.

This results in things like this:
```rust
TokenTree::token(token::Semi, stmt.span).into()
```
changing to this:
```rust
TokenStream::token_alone(token::Semi, stmt.span)
```
This makes the type of the result, and its spacing, clearer.

These changes also simplifies `Cursor` and `CursorRef`, because they no longer
need to distinguish between `next` and `next_with_spacing`.
2022-07-29 15:52:15 +10:00
bors 61c6d16ade Auto merge of #99660 - PrestonFrom:issue_99265, r=compiler-errors
Generate correct suggestion with named arguments used positionally

Address issue #99265 by checking each positionally used argument
to see if the argument is named and adding a lint to use the name
instead. This way, when named arguments are used positionally in a
different order than their argument order, the suggested lint is
correct.

For example:
```
println!("{b} {}", a=1, b=2);
```
This will now generate the suggestion:
```
println!("{b} {a}", a=1, b=2);
```

Additionally, this check now also correctly replaces or inserts
only where the positional argument is (or would be if implicit).
Also, width and precision are replaced with their argument names
when they exists.

Since the issues were so closely related, this fix for issue #99265
also fixes issue #99266.

Fixes #99265
Fixes #99266
2022-07-29 04:23:08 +00:00
Philipp Krones 67c405cc1d Merge commit '3c7e7dbc1583a0b06df5bd7623dd354a4debd23d' into clippyup 2022-07-28 19:08:22 +02:00
Guillaume Gomez c31637e082 Rollup merge of #99728 - cjgillot:ast-lifetimes-anon-clean, r=petrochenkov
Clean up HIR-based lifetime resolution

Based on https://github.com/rust-lang/rust/pull/97313.

Fixes #98932.

r? `@petrochenkov`
2022-07-27 17:55:07 +02:00
David Wood 257259118c lint: add bad opt access internal lint
Some command-line options accessible through `sess.opts` are best
accessed through wrapper functions on `Session`, `TyCtxt` or otherwise,
rather than through field access on the option struct in the `Session`.

Adds a new lint which triggers on those options that should be accessed
through a wrapper function so that this is prohibited. Options are
annotated with a new attribute `rustc_lint_opt_deny_field_access` which
can specify the error message (i.e. "use this other function instead")
to be emitted.

A simpler alternative would be to simply rename the options in the
option type so that it is clear they should not be used, however this
doesn't prevent uses, just discourages them. Another alternative would
be to make the option fields private, and adding accessor functions on
the option types, however the wrapper functions sometimes rely on
additional state from `Session` or `TyCtxt` which wouldn't be available
in an function on the option type, so the accessor would simply make the
field available and its use would be discouraged too.

Signed-off-by: David Wood <david.wood@huawei.com>
2022-07-27 11:24:27 +01:00
Camille GILLOT 8edcf6cd1e Clippy fallout. 2022-07-26 19:00:31 +02:00
Camille GILLOT 034b6f99ad Replace LifetimeRes::Anonymous by LifetimeRes::Infer. 2022-07-26 19:00:31 +02:00
bors 6654aabb0f Auto merge of #97313 - cjgillot:ast-lifetimes-anon, r=petrochenkov
Resolve function lifetime elision on the AST

~Based on https://github.com/rust-lang/rust/pull/97720~

Lifetime elision for functions is purely syntactic in nature, so can be resolved on the AST.
This PR replicates the elision logic and diagnostics on the AST, and replaces HIR-based resolution by a `delay_span_bug`.

This refactor allows for more consistent diagnostics, which don't have to guess the original code from HIR.

r? `@petrochenkov`
2022-07-25 20:02:55 +00:00
Camille GILLOT 419d39c072 Clippy fallout. 2022-07-25 19:19:23 +02:00
Preston From af8ae10678 Generate correct suggestion with named arguments used positionally
Address issue #99265 by checking each positionally used argument
to see if the argument is named and adding a lint to use the name
instead. This way, when named arguments are used positionally in a
different order than their argument order, the suggested lint is
correct.

For example:
```
println!("{b} {}", a=1, b=2);
```
This will now generate the suggestion:
```
println!("{b} {a}", a=1, b=2);
```

Additionally, this check now also correctly replaces or inserts
only where the positional argument is (or would be if implicit).
Also, width and precision are replaced with their argument names
when they exists.

Since the issues were so closely related, this fix for issue #99265
also fixes issue #99266.

Fixes #99265
Fixes #99266
2022-07-25 00:00:27 -06:00
Michael Goulet 632f9945d6 Do not resolve associated const when there is no provided value 2022-07-22 18:58:07 +00:00
Oli Scherer bcd2241c9a Revert "Rollup merge of #98582 - oli-obk:unconstrained_opaque_type, r=estebank"
This reverts commit 6f8fb911ad, reversing
changes made to 7210e46dc6.
2022-07-20 07:55:58 +00:00
Michael Goulet 30a9533570 Mention first and last macro in backtrace 2022-07-19 03:07:54 +00:00
Philipp Krones 7d4daaa8fa Merge commit 'fdb84cbfd25908df5683f8f62388f663d9260e39' into clippyup 2022-07-18 09:39:37 +02:00
Caio f88a1399bb Stabilize `let_chains` 2022-07-16 20:17:58 -03:00
Matthias Krüger 2300da4412 Rollup merge of #99342 - TaKO8Ki:avoid-symbol-to-string-conversions, r=compiler-errors
Avoid some `Symbol` to `String` conversions

This patch removes some Symbol to String conversions.
2022-07-16 22:30:56 +02:00
Takayuki Maeda a2c6252cd3 avoid some `Symbol` to `String` conversions 2022-07-17 04:09:20 +09:00
Oli Scherer 417a600c30 Introduce opaque type to hidden type projection 2022-07-15 15:49:22 +00:00
bors 6dc9746147 Auto merge of #95956 - yaahc:stable-in-unstable, r=cjgillot
Support unstable moves via stable in unstable items

part of https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/moving.20items.20to.20core.20unstably and a blocker of https://github.com/rust-lang/rust/pull/90328.

The libs-api team needs the ability to move an already stable item to a new location unstably, in this case for Error in core. Otherwise these changes are insta-stable making them much harder to merge.

This PR attempts to solve the problem by checking the stability of path segments as well as the last item in the path itself, which is currently the only thing checked.
2022-07-14 13:42:09 +00:00