Extend rules of dead code analysis for impls for adts to impls for types refer to adts
The rules of dead code analysis for impl blocks can be extended to self types which refer to adts.
So that we can lint the following unused struct and trait:
```rust
struct Foo; //~ ERROR struct `Foo` is never constructed
trait Trait { //~ ERROR trait `Trait` is never used
fn foo(&self) {}
}
impl Trait for &Foo {}
```
r? `@pnkfelix`
Implement lint against ambiguous negative literals
This PR implements a lint against ambiguous negative literals with a literal and method calls right after it.
## `ambiguous_negative_literals`
(deny-by-default)
The `ambiguous_negative_literals` lint checks for cases that are confusing between a negative literal and a negation that's not part of the literal.
### Example
```rust,compile_fail
-1i32.abs(); // equals -1, while `(-1i32).abs()` equals 1
```
### Explanation
Method calls take precedence over unary precedence. Setting the precedence explicitly makes the code clearer and avoid potential bugs.
<details>
<summary>Old proposed lint</summary>
## `ambiguous_unary_precedence`
(deny-by-default)
The `ambiguous_unary_precedence` lint checks for use the negative unary operator with a literal and method calls.
### Example
```rust
-1i32.abs(); // equals -1, while `(-1i32).abs()` equals 1
```
### Explanation
Unary operations take precedence on binary operations and method calls take precedence over unary precedence. Setting the precedence explicitly makes the code clearer and avoid potential bugs.
</details>
-----
Note: This is a strip down version of https://github.com/rust-lang/rust/pull/117161, without the binary op precedence.
Fixes https://github.com/rust-lang/rust/issues/117155
`@rustbot` labels +I-lang-nominated
cc `@scottmcm`
r? compiler
Replace ASCII control chars with Unicode Control Pictures
Replace ASCII control chars like `CR` with Unicode Control Pictures like `␍`:
```
error: bare CR not allowed in doc-comment
--> $DIR/lex-bare-cr-string-literal-doc-comment.rs:3:32
|
LL | /// doc comment with bare CR: '␍'
| ^
```
Centralize the checking of unicode char width for the purposes of CLI display in one place. Account for the new replacements. Remove unneeded tracking of "zero-width" unicode chars, as we calculate these in the `SourceMap` as needed now.
We are moving toward forbidding `missing_fragment_specifier` either in
edition 2024 or unconditionally. Make a first step toward this by
ensuring crates that rely on the old behavior are reported when used as
dependencies.
Tracking issue: <https://github.com/rust-lang/rust/issues/128143>
No longer track "zero-width" chars in `SourceMap`, read directly from the line when calculating the `display_col` of a `BytePos`. Move `char_width` to `rustc_span` and use it from the emitter.
This change allows the following to properly align in terminals (depending on the font, the replaced control codepoints are rendered as 1 or 2 width, on my terminal they are rendered as 1, on VSCode text they are rendered as 2):
```
error: this file contains an unclosed delimiter
--> $DIR/issue-68629.rs:5:17
|
LL | ␜␟ts␀).
However this node is not shown for variants that have fields in enum. This PR fixes to show the note.
Fix assertion failure for some `Expect` diagnostics.
In #120699 I moved some code dealing with `has_future_breakage` earlier in `emit_diagnostic`. Issue #126521 identified a case where that reordering was invalid (leading to an assertion failure) for some `Expect` diagnostics.
This commit partially undoes the change, by moving the handling of unstable `Expect` diagnostics earlier again. This makes `emit_diagnostic` a bit uglier, but is necessary to fix the problem.
Fixes#126521.
r? ``@oli-obk``
In #120699 I moved some code dealing with `has_future_breakage` earlier
in `emit_diagnostic`. Issue #126521 identified a case where that
reordering was invalid (leading to an assertion failure) for some `Expect`
diagnostics.
This commit partially undoes the change, by moving the handling of
unstable `Expect` diagnostics earlier again. This makes
`emit_diagnostic` a bit uglier, but is necessary to fix the problem.
Fixes#126521.
Suggest removing unused tuple fields if they are the last fields
Fixes#124556
We now check if dead/unused fields are the last fields of the tuple and suggest their removal instead of suggesting them to be changed to `()`.
tests/ui/lint: Move 19 tests to new `non-snake-case` subdir
Mainly so that it is easier to only run all `non_snake_case`-lint-specific tests with:
./x test tests/ui/lint/non-snake-case
But also to reduce the size of the large `tests/ui/lint` directory. And rename some tests to pass tidy, and remove them from `src/tools/tidy/src/issues.txt`.
Mainly so that it is easier to only run all `non-snake-case`-specific
tests but no other tests with:
./x test tests/ui/lint/non-snake-case
But also to reduce the size of the large `tests/ui/lint` directory. And
rename some tests to pass tidy, and remove them from
`src/tools/tidy/src/issues.txt`.
Tweak output of import suggestions
When both `std::` and `core::` items are available, only suggest the `std::` ones. We ensure that in `no_std` crates we suggest `core::` items.
Ensure that the list of items suggested to be imported are always in the order of local crate items, `std`/`core` items and finally foreign crate items.
Tweak wording of import suggestion: if there are multiple items but they are all of the same kind, we use the kind name and not the generic "items".
Fix#83564.
Add pub struct with allow(dead_code) into worklist
<!--
If this PR is related to an unstable feature or an otherwise tracked effort,
please link to the relevant tracking issue here. If you don't know of a related
tracking issue or there are none, feel free to ignore this.
This PR will get automatically assigned to a reviewer. In case you would like
a specific user to review your work, you can assign it to them by using
r? <reviewer name>
-->
Fixes#126289
When both `std::` and `core::` items are available, only suggest the
`std::` ones. We ensure that in `no_std` crates we suggest `core::`
items.
Ensure that the list of items suggested to be imported are always in the
order of local crate items, `std`/`core` items and finally foreign crate
items.
Tweak wording of import suggestion: if there are multiple items but they
are all of the same kind, we use the kind name and not the generic "items".
Fix#83564.
Detect pub structs never constructed and unused associated constants
<!--
If this PR is related to an unstable feature or an otherwise tracked effort,
please link to the relevant tracking issue here. If you don't know of a related
tracking issue or there are none, feel free to ignore this.
This PR will get automatically assigned to a reviewer. In case you would like
a specific user to review your work, you can assign it to them by using
r? <reviewer name>
-->
Lints never constructed public structs.
If we don't provide public methods to construct public structs with private fields, and don't construct them in the local crate. They would be never constructed. So that we can detect such public structs.
---
Update:
Also lints unused associated constants in traits.
Revert: create const block bodies in typeck via query feeding
as per the discussion in https://github.com/rust-lang/rust/pull/125806#discussion_r1622563948
It was a mistake to try to shoehorn const blocks and some specific anon consts into the same box and feed them during typeck. It turned out not simplifying anything (my hope was that we could feed `type_of` to start avoiding the huge HIR matcher, but that didn't work out), but instead making a few things more fragile.
reverts the const-block-specific parts of https://github.com/rust-lang/rust/pull/124650
`@bors` rollup=never had a small perf impact previously
fixes https://github.com/rust-lang/rust/issues/125846
r? `@compiler-errors`
Revert "Disallow ambiguous attributes on expressions" on nightly
As discussed in [today's t-compiler meeting](https://rust-lang.zulipchat.com/#narrow/stream/238009-t-compiler.2Fmeetings/topic/.5Bweekly.5D.202024-06-06/near/443079505), this reverts PR #124099 to fix P-critical beta regressions #125199.
r? ``@wesleywiser``
Opening as draft so that ``@wesleywiser`` and ``@apiraino,`` you can tell me whether you wanted:
1. a `beta-accepted` revert of #124099 on nightly (this PR)? That will need to be backported to beta (even though #126093 may be the last of those)
2. a revert of #124099 on beta?
3. all of the above?
I also opened #126102, another draft PR to revert #124099 on beta, should you choose options 2 or 3.