Add new `duplicated_attributes` lint
It's a lint idea that `@llogiq` gave me while reviewing another PR.
There are some limitations, in particular for the "output". Initially I wanted to make it possible for directly lint against the whole attribute if its parts were all duplicated, but then I realized that the output would be chaotic if the duplicates were coming from different attributes, so I preferred to go to the simplest way and simply emit a warning for each entry. Not the best, but makes the implementation much easier.
Another limitation is that `cfg_attr` would be a bit more tricky to implement because we need to check if two `cfg` sets are exactly the same. I added a FIXME and will likely come back to it later.
And finally, I updated the `cargo dev update_lints` command because the generated `tests/ui/rename.rs` file was emitting the `duplicated_attributes` lint, so I allowed this lint inside it to prevent it from working.
changelog: Add new `duplicated_attributes` lint
New lint `const_is_empty`
This lint detects calls to `.is_empty()` on an entity initialized from a string literal and flag them as suspicious. To avoid triggering on macros called from generated code, it checks that the `.is_empty()` receiver, the call itself and the initialization come from the same context.
Fixes#12307
changelog: [`const_is_empty`]: new lint
Add new `mixed_attributes_style` lint
Add a new lint to detect cases where both inner and outer attributes are used on a same item.
r? `@llogiq`
----
changelog: Add new [`mixed_attributes_style`] lint
Alphabetize configuration options and lints in Clippy documentation
changelog: alphabetize configuration options and affected lints listed in section 3.1. of the Clippy Documentation
r? blyxyas
Empty docs
Fixes https://github.com/rust-lang/rust-clippy/issues/9931
changelog: [`empty_doc`]: Detects documentation that is empty.
changelog: Doc comment lints now trigger for struct field and enum variant documentation
Add new lint: `ref_as_ptr`
Fixes#10130
Added new lint `ref_as_ptr` that checks for conversions from references to pointers and suggests using `std::ptr::from_{ref, mut}` instead.
The name is different than suggested in the issue (`as_ptr_cast`) since there were some other lints with similar names (`ptr_as_ptr`, `borrow_as_ptr`) and I wanted to follow the convention.
Note that this lint conflicts with the `borrow_as_ptr` lint in the sense that it recommends changing `&foo as *const _` to `std::ptr::from_ref(&foo)` instead of `std::ptr::addr_of!(foo)`. Personally, I think the former is more readable and, in contrast to `addr_of` macro, can be also applied to temporaries (cf. #9884).
---
changelog: New lint: [`ref_as_ptr`]
[#12087](https://github.com/rust-lang/rust-clippy/pull/12087)
add configuration for [`wildcard_imports`] to ignore certain imports
fixes: #11428
changelog: add configuration `ignored-wildcard-imports` for lint [`wildcard_imports`]
Checks for the suspicious use of OpenOptions::create()
without an explicit OpenOptions::truncate().
create() alone will either create a new file or open an
existing file. If the file already exists, it will be
overwritten when written to, but the file will not be
truncated by default. If less data is written to the file
than it already contains, the remainder of the file will
remain unchanged, and the end of the file will contain old
data.
In most cases, one should either use `create_new` to ensure
the file is created from scratch, or ensure `truncate` is
called so that the truncation behaviour is explicit.
`truncate(true)` will ensure the file is entirely overwritten
with new data, whereas `truncate(false)` will explicitely
keep the default behavior.
```rust
use std::fs::OpenOptions;
OpenOptions::new().create(true).truncate(true);
```
Adds a new lint to suggest using `const` on `thread_local!`
initializers that can be evaluated at compile time.
Impl details:
The lint relies on the expansion of `thread_local!`. For non
const-labelled initializers, `thread_local!` produces a function
called `__init` that lazily initializes the value. We check the function
and decide whether the body can be const. The body of the function is
exactly the initializer. If so, we lint the body.
changelog: new lint [`thread_local_initializer_can_be_made_const`]
New Lint: empty_enum_variants_with_brackets
This PR:
- adds a new early pass lint that checks for enum variants with no fields that were defined using brackets. **Category: Restriction**
- adds relevant UI tests for the new lint.
Closes#12007
```
changelog: New lint: [`empty_enum_variants_with_brackets`]
```
feat: add `manual_is_variant_and` lint
changelog: add a new lint [`manual_is_variant_and`].
- Replace `option.map(f).unwrap_or_default()` and `result.map(f).unwrap_or_default()` with `option.is_some_and(f)` and `result.is_ok_and(f)` where `f` is a function or closure that returns `bool`.
- MSRV is set to 1.70.0 for this lint; when `is_some_and` and `is_ok_and` was stabilised
---
For example, for the following code:
```rust
let opt = Some(0);
opt.map(|x| x > 1).unwrap_or_default();
```
It suggests to instead write:
```rust
let opt = Some(0);
opt.is_some_and(|x| x > 1)
```
- add a new late pass lint, with config options
- add ui tests for both variations of config option
- update CHANGELOG.md
github feedback
bump version to 1.77 and run cargo collect-metadata
Change `,` to `;` in `conf.rs`
new lint: `eager_transmute`
A small but still hopefully useful lint that looks for patterns such as `(x < 5).then_some(transmute(x))`.
This is almost certainly wrong because it evaluates the transmute eagerly and can lead to surprises such as the check being completely removed and always evaluating to `Some` no matter what `x` is (it is UB after all when the integer is not a valid bitpattern for the transmuted-to type). [Example](https://godbolt.org/z/xoY34fPzh).
The user most likely meant to use `then` instead.
I can't remember where I saw this but this is inspired by a real bug that happened in practice.
This could probably be a correctness lint?
changelog: new lint: [`eager_int_transmute`]