[`redundant_locals`]: take by-value closure captures into account
Fixes#12225
The same problem in the linked issue can happen to regular closures too, and conveniently async blocks are closures in the HIR so fixing closures will fix async blocks as well.
changelog: [`redundant_locals`]: avoid linting when redefined variable is captured by-value
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)
Fixed FP in `unused_io_amount` for Ok(lit), unrachable! and unwrap de…
…sugar
Fixes fp caused by linting on Ok(_) for all cases outside binding.
We introduce the following rules for match exprs.
- `panic!` and `unreachable!` are treated as consumed.
- `Ok( )` patterns outside `DotDot` and `Wild` are treated as consuming.
changelog: FP [`unused_io_amount`] when matching Ok(literal) or unreachable
fixes#12208
r? `@blyxyas`
We introduce the following rules for match exprs.
- `panic!` and `unreachable!` are treated as consumption.
- guard expressions in any arm imply consumption.
For match exprs:
- Lint only if exacrtly 2 non-consuming arms exist
- Lint only if one arm is an `Ok(_)` and the other is `Err(_)`
Added additional requirement that for a block return expression
that is a match, the source must be `Normal`.
changelog: FP [`unused_io_amount`] when matching Ok(literal)
Add regression ui test for #2371Fixes#2371.
#2371 seems to already be handled correctly in the lint. This PR adds a ui regression test so we can close it.
r? `@blyxyas`
changelog: Add regression ui test for #2371
[fix] [`redundant_closure_for_method_calls`] Suggest relative paths for local modules
Fixes#10854.
Currently, `redundant_closure_for_method_calls` suggest incorrect paths when a method defined on a struct within inline mod is referenced (see the description in the aforementioned issue for an example; also see [this playground link](https://play.rust-lang.org/?version=stable&mode=release&edition=2021&gist=f7d3c5b2663c9bd3ab7abdb0bd38ee43) for the current-version output for the test cases added in this PR). It will now try to construct a relative path path to the module and suggest it instead.
changelog: [`redundant_closure_for_method_calls`] Fix incorrect path suggestions for types within local modules
FP: `needless_return_with_question_mark` with implicit Error Conversion
Return with a question mark was triggered in situations where the `?` desuraging was performing error conversion via `Into`/`From`.
The desugared `?` produces a match over an expression with type `std::ops::ControlFlow<B,C>` with `B:Result<Infallible, E:Error>` and `C:Result<_, E':Error>`, and the arms perform the conversion. The patch adds another check in the lint that checks that `E == E'`. If `E == E'`, then the `?` is indeed unnecessary.
changelog: False Positive: [`needless_return_with_question_mark`] when implicit Error Conversion occurs.
fixes: #11982
fix: incorrect suggestions generated by `manual_retain` lint
fixes#10393, fixes#11457, fixes#12081#10393: In the current implementation of `manual_retain`, if the argument to the closure is matched using tuple, they are all treated as the result of a call to `map.into_iter().filter(<f>)`. However, such tuple pattern matching can also occur in many different containers that stores tuples internally. The correct approach is to apply different lint policies depending on whether the receiver of `into_iter` is a map or not.
#11457 and #12081: In the current implementation of `manual_retain`, if the argument to the closure is `Binding`, the closure will be used directly in the `retain` method, which will result in incorrect suggestion because the first argument to the `retain` closure may be of a different type. In addition, if the argument to the closure is `Ref + Binding`, the lint will simply remove the `Ref` part and use the `Binding` part as the argument to the new closure, which will lead to bad suggestion for the same reason. The correct approach is to detect each of these cases and apply lint suggestions conservatively.
changelog: [`manual_retain`] refactor and add check for various patterns
Fix/Issue11932: assert* in multi-condition after unrolling will cause lint `nonminimal_bool` emit warning
fixes [Issue#11932](https://github.com/rust-lang/rust-clippy/issues/11932)
After `assert`, `assert_eq`, `assert_ne`, etc, assert family marcos unrolling in multi-condition expressions, lint `nonminimal_bool` will recognize whole expression as a entirety, analyze each simple condition expr of them, and check whether can simplify them.
But `assert` itself is a entirety to programmers, we don't need to lint on `assert`. This commit add check whether lint snippet contains `assert` when try to warning to an expression.
changelog: [`nonminimal_bool`] add check for condition expression
[`never_loop`]: recognize desugared `try` blocks
Fixes#12205
The old code assumed that only blocks with an explicit label can be jumped to (using `break`). This is mostly correct except for `try` desugaring, where the `?` operator is rewritten to a `break` to that block, even without a label on the block. `Block::targeted_by_break` is a little more accurate than just checking if a block has a label in that regard, so we should just use that instead
changelog: [`never_loop`]: avoid linting when `?` is used inside of a try block
Fixed FP in `redundant_closure_call` when closures are passed to macros
There are cases where the closure call is needed in some macros, this in particular occurs when the closure has parameters. To handle this case, we allow the lint when there are no parameters in the closure, or the closure is outside a macro invocation.
fixes: #11274#1553
changelog: FP: [`redundant_closure_call`] when closures with parameters are passed in macros.
Warn if an item coming from more recent version than MSRV is used
Part of https://github.com/rust-lang/rust-clippy/issues/6324.
~~Currently, the lint is not working for the simple reason that the `stable` attribute is not kept in dependencies. I'll send a PR to rustc to see if they'd be okay with keeping it.~~
EDIT: There was actually a `lookup_stability` function providing this information, so all good now!
cc `@epage`
changelog: create new [`incompatible_msrv`] lint
respect `#[allow]` attributes in `single_call_fn` lint
Fixes#12182
If we delay linting to `check_crate_post`, we need to use `span_lint_hir_and_then`, since otherwise it would only respect those lint level attributes at the crate root.
<sub>... maybe we can have an internal lint for this somehow?</sub>
changelog: respect `#[allow]` attributes in `single_call_fn` lint
Don't emit `derive_partial_eq_without_eq` lint if the type has the `non_exhaustive` attribute
Part of https://github.com/rust-lang/rust-clippy/issues/9063.
If a type has a field/variant with the `#[non_exhaustive]` attribute or the type itself has it, then do no emit the `derive_partial_eq_without_eq` lint.
changelog: Don't emit `derive_partial_eq_without_eq` lint if the type has the `non_exhaustive` attribute
`unused_io_amount` captures `Ok(_)`s
Partial rewrite of `unused_io_amount` to lint over `Ok(_)` and `Ok(..)`.
Moved the check to `check_block` to simplify context checking for expressions and allow us to check only some expressions.
For match (expr, arms) we emit a lint for io ops used on `expr` when an arm is `Ok(_)|Ok(..)`. Also considers the cases when there are guards in the arms and `if let Ok(_) = ...` cases.
For `Ok(_)` and `Ok(..)` it emits a note indicating where the value is ignored.
changelog: False Negatives [`unused_io_amount`]: Extended `unused_io_amount` to catch `Ok(_)`s in `If let` and match exprs.
Closes#11713
r? `@giraffate`
Partial rewrite of `unused_io_account` to lint over Ok(_).
Moved the check to `check_block` to simplify context checking for
expressions and allow us to check only some expressions.
For match (expr, arms) we emit a lint for io ops used on `expr` when an
arm is `Ok(_)`. Also considers the cases when there are guards in the
arms. It also captures `if let Ok(_) = ...` cases.
For `Ok(_)` it emits a note indicating where the value is ignored.
changelog: False Negatives [`unused_io_amount`]: Extended
`unused_io_amount` to catch `Ok(_)`s in `If let` and match exprs.
Prefixing a variable with a `_` does not mean that it will not be used.
If such a variable is used later, do not warn about the fact that its
initialization does not have a side effect as this is fine.
Fix error warning span for issue12045
fixes [Issue#12045](https://github.com/rust-lang/rust-clippy/issues/12045)
In issue#12045, unexpected warning span occurs on attribute `#[derive(typed_builder::TypedBuilder)]`, actually the warning should underline `_lifetime`.
In the source code we can find that the original intend is to warning on `ident.span`, but in this case, `stmt.span` is unequal with `ident.span`. So, fix the nit here is fine.
Besides, `ident.span` have an accurate range than `stmt.span`.
changelog: [`no_effect_underscore_binding`]: correct warning span
fix FP on [`semicolon_if_nothing_returned`]
fixes: #12123
---
changelog: fix FP on [`semicolon_if_nothing_returned`] which suggesting adding semicolon after attr macro
Correctly handle type relative in trait_duplication_in_bounds lint
Fixes#9961.
The generic bounds were not correctly checked and left out `QPath::TypeRelative`, making different bounds look the same and generating invalid errors (and fix).
r? `@blyxyas`
changelog: [`trait_duplication_in_bounds`]: Correctly handle type relative.
`read_zero_byte_vec` refactor for better heuristics
Fixes#9274
Previously, the implementation of `read_zero_byte_vec` only checks for the next statement after the vec init. This fails when there is a block with statements that are expanded and walked by the old visitor.
This PR refactors so that:
1. It checks if there is a `resize` on the vec
2. It works on blocks properly
e.g. This should properly lint now:
```
let mut v = Vec::new();
{
f.read(&mut v)?;
//~^ ERROR: reading zero byte data to `Vec`
}
```
changelog: [`read_zero_byte_vec`] Refactored for better heuristics
Add suspicious_open_options lint.
changelog: [`suspicious_open_options`]: Checks for the suspicious use of std::fs::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);
```
- [x] Followed [lint naming conventions][lint_naming]
- [x] Added passing UI tests (including committed `.stderr` file)
- [x] `cargo test` passes locally
- [x] Executed `cargo dev update_lints`
- [x] Added lint documentation
- [x] Run `cargo dev fmt`
