New lint: [`derive_partial_eq_without_eq`]
Introduces a new lint, [`derive_partial_eq_without_eq`].
See: #1781 (doesn't close it though).
changelog: add lint [`derive_partial_eq_without_eq`]
Support tool lints with the `#[expect]` attribute (RFC 2383)
This PR fixes the ICE https://github.com/rust-lang/rust/issues/94953 by making the assert for converted expectation IDs conditional.
Additionally, it moves the lint expectation check into a separate query to support rustdoc and other tools. On the way, I've also added some tests to ensure that the attribute works for Clippy and rustdoc lints.
The number of changes comes from the long test file. This may look like a monster PR, this may smell like a monster PR and this may be a monster PR, but it's a harmless monster. 🦕
---
Closes: https://github.com/rust-lang/rust/issues/94953
cc: https://github.com/rust-lang/rust/issues/85549
r? `@wesleywiser`
cc: `@rust-lang/rustdoc`
Track if a where bound comes from a impl Trait desugar
With https://github.com/rust-lang/rust/pull/93803 `impl Trait` function arguments get desugared to hidden where bounds. However, Clippy needs to know if a bound was originally a `impl Trait` or an actual bound. This adds a field to the `WhereBoundPredicate` struct to keep track of this information during AST->HIR lowering.
r? `@cjgillot`
cc `@estebank` (as the reviewer of #93803)
Address `unnecessary_to_owned` false positive
My proposed fix for #8759 is to revise the conditions that delineate `redundant_clone` and `unnecessary_to_owned`:
```rust
// Only flag cases satisfying at least one of the following three conditions:
// * the referent and receiver types are distinct
// * the referent/receiver type is a copyable array
// * the method is `Cow::into_owned`
// This restriction is to ensure there is no overlap between `redundant_clone` and this
// lint. It also avoids the following false positive:
// https://github.com/rust-lang/rust-clippy/issues/8759
// Arrays are a bit of a corner case. Non-copyable arrays are handled by
// `redundant_clone`, but copyable arrays are not.
```
This change causes a few cases that were previously flagged by `unnecessary_to_owned` to no longer be flagged. But one could argue those cases would be better handled by `redundant_clone`.
Closes#8759
changelog: none
Allow inline consts to reference generic params
Tracking issue: #76001
The RFC says that inline consts cannot reference to generic parameters (for now), same as array length expressions. And expresses that it's desirable for it to reference in-scope generics, when array length expressions gain that feature as well.
However it is possible to implement this for inline consts before doing this for all anon consts, because inline consts are only used as values and they won't be used in the type system. So we can have:
```rust
fn foo<T>() {
let x = [4i32; std::mem::size_of::<T>()]; // NOT ALLOWED (for now)
let x = const { std::mem::size_of::<T>() }; // ALLOWED with this PR!
let x = [4i32; const { std::mem::size_of::<T>() }]; // NOT ALLOWED (for now)
}
```
This would make inline consts super useful for compile-time checks and assertions:
```rust
fn assert_zst<T>() {
const { assert!(std::mem::size_of::<T>() == 0) };
}
```
This would create an error during monomorphization when `assert_zst` is instantiated with non-ZST `T`s. A error during mono might sound scary, but this is exactly what a "desugared" inline const would do:
```rust
fn assert_zst<T>() {
struct F<T>(T);
impl<T> F<T> {
const V: () = assert!(std::mem::size_of::<T>() == 0);
}
let _ = F::<T>::V;
}
```
It should also be noted that the current inline const implementation can already reference the type params via type inference, so this resolver-level restriction is not any useful either:
```rust
fn foo<T>() -> usize {
let (_, size): (PhantomData<T>, usize) = const {
const fn my_size_of<T>() -> (PhantomData<T>, usize) {
(PhantomData, std::mem::size_of::<T>())
}
my_size_of()
};
size
}
```
```@rustbot``` label: F-inline_const
Support negative ints in manual_range_contains
fixes: #8721
changelog: Fixes issue where ranges containing ints with different signs would be
incorrect due to comparing as unsigned.
Fix `cast_lossless` to avoid warning on `usize` to `f64` conversion.
Previously, the `cast_lossless` lint would issue a warning on code that
converted a `usize` value to `f64`, on 32-bit targets.
`usize` to `f64` is a lossless cast on 32-bit targets, however there is
no corresponding `f64::from` that takes a `usize`, so `cast_lossless`'s
suggested replacement does not compile.
This PR disables the lint in the case of casting from `usize` or `isize`.
Fixes#3689.
changelog: [`cast_lossless`] no longer gives wrong suggestion on usize,isize->f64
Those lints are trait_duplication_in_bounds and
type_repetition_in_bounds. I don't think those can be fixed on the
Clippy side alone, but need changes in the compiler. So let's move them
to nursery to get the sync through and then fix them on the rustc side.
Also adds a regression test that has to be fixed before they can be
moved back to pedantic.
[FP] identity_op in front of if
fix#8724
changelog: FP: [`identity_op`]: is now allowed in front of if statements, blocks and other expressions where the suggestion would be invalid.
Resolved simular problems with blocks, mathces, and loops.
identity_op always does NOT suggest reducing `0 + if b { 1 } else { 2 } + 3` into `if b { 1 } else { 2 } + 3` even in the case that the expression is in `f(expr)` or `let x = expr;` for now.
Previously, the `cast_lossless` lint would issue a warning on code that
converted a `usize` value to `f64`, on 32-bit targets.
`usize` to `f64` is a lossless cast on 32-bit targets, however there is
no corresponding `f64::from` that takes a `usize`, so `cast_lossless`'s
suggested replacement does not compile.
This PR disables the lint in the case of casting from `usize` or `isize`.
Fixes#3689.
changelog: [`cast_lossless`] no longer gives wrong suggestion on usize->f64
ignore `redundant_pub_crate` in `useless_attribute`
changelog: [`useless_attribute`] no longer lints [`redundant_pub_crate`]
As mentioned in https://github.com/rust-lang/rust-clippy/issues/8732#issuecomment-1106489634
> And it turns out I can't even explicitly allow it at the usage site, because then `clippy::useless_attribute` fires (which would also be a FP?), which is deny-by-default.
>
> Though it does work if I then allow `clippy::useless_attribute`. 😂
>
> ```rust
> #[allow(clippy::useless_attribute)]
> #[allow(clippy::redundant_pub_crate)]
> pub(crate) use bit;
> ```
>
> The originally-reported warning now no longer occurs.
`needless_late_init`: ignore `if let`, `let mut` and significant drops
No longer lints `if let`, personal taste on this one is pretty split, so it probably shouldn't be warning by default. Fixes#8613
```rust
let x = if let Some(n) = y {
n
} else {
1
}
```
No longer lints `let mut`, things like the following are not uncommon and look fine as they are
b169c16d86/src/sixty_four.rs (L88-L93)
Avoids changing the drop order in an observable way, where the type of `x` has a drop with side effects and something between `x` and the first use also does, e.g.
48cc6cb791/tests/test_api.rs (L159-L167)
The implementation of `type_needs_ordered_drop_inner` was changed a bit, it now uses `Ty::has_significant_drop` and reordered the ifs to check diagnostic name before checking the implicit drop impl
changelog: [`needless_late_init`]: No longer lints `if let` statements, `let mut` bindings and no longer significantly changes drop order
mistyped_literal_suffix: improve integer suggestions, avoid wrong float suggestions
This PR fixes 2 things:
- The known problem that integer types are always suggested as signed, by suggesting an unsigned suffix for literals that wouldnt fit in the signed type, and ignores any literals too big for the corresponding unsigned type too.
- The lint would only look at the integer part of any floating point literals without an exponent, this causing #6129. This just ignores those literals.
Examples:
```rust
let _ = 2_32; // still 2_i32
let _ = 234_8; // would now suggest 234_u8
// these are now ignored
let _ = 500_8;
let _ = 123_32.123;
```
changelog: suggest correct integer types in [`mistyped_literal_suffix`], ignore float literals without an exponent
fixes#6129
Previously this lint would only look at the integer part of floating
point literals without an exponent, giving wrong suggestions like:
```
|
8 | let _ = 123_32.123;
| ^^^^^^^^^^ help: did you mean to write: `123.123_f32`
|
```
Instead, it now ignores these literals.
Fixes#6129
Instead of just always suggesting signed suffixes regardless of size
of the value, it now suggests an unsigned suffix when the value wouldn't
fit into the corresponding signed type, and ignores the literal entirely
if it is too big for the unsigned type as well.
wrong_self_convention allows `is_*` to take `&mut self`
fix#8480 and #8513
Allowing `is_*` to take `&self` or none is too restrictive.
changelog: FPs: [`wrong_self_convention`] now allows `&mut self` and no self as arguments for `is_*` methods
