Add details about how significant drop in match scrutinees can cause deadlocks
Adds more details about how a significant drop in a match scrutinee can cause a deadlock and include link to documentation.
changelog: Add more details to significant drop lint to explicitly show how temporaries in match scrutinees can cause deadlocks.
Lint `[single_match]` on `Option` matches
fixes#8928
changelog: did some cleanup of the logic for ``[`single_match`]`` and ``[`single_match_else`]`` which fixes the bug where `Option` matches were not linted unless a wildcard was used for one of the arms.
Adds more details about how a significant drop in a match scrutinee can
cause a deadlock and include link to documentation. Emits messages
indicating temporaries with significant drops in arms of matches and
message about possible deadlocks/unexpected behavior.
changelog: Add more details to significant drop lint to explicitly show
how temporaries in match scrutinees can cause deadlocks/unexpected
behavior.
Make `ExprKind::Closure` a struct variant.
Simple refactor since we both need it to introduce additional fields in `ExprKind::Closure`.
r? ``@Aaron1011``
Replace `#[allow]` with `#[expect]` in Clippy
Hey `@rust-lang/clippy,` `@Alexendoo,` `@dswij,` I'm currently working on the expect attribute as defined in [Rust RFC 2383](https://rust-lang.github.io/rfcs/2383-lint-reasons.html). With that, an `#[allow]` attribute can be replaced with a `#[expect]` attribute that suppresses the lint, but also emits a warning, if the lint isn't emitted in the expected scope.
With this PR I would like to test the attribute on a project scale and Clippy obviously came to mind. This PR replaces (almost) all `#[allow]` attributes in `clippy_utils` and `clippy_lints` with the `#[expect]` attribute. I was also able to remove some allows since, the related FPs have been fixed 🎉.
My question is now, are there any concerns regarding this? It's still okay to add normal `#[allow]` attributes, I see the need to nit-pick about that in new PRs, unless it's actually a FP. Also, I would not recommend using `#[expect]` in tests, as changes to a lint could the trigger the expect attribute in other files.
Additionally, I've noticed that Clippy has a bunch of `#[allow(clippy::too_many_lines)]` attributes. Should we maybe allow the lint all together or increase the threshold setting? To me, it seems like we mostly just ignore it in our code. 😅🙃
---
changelog: none
r? `@flip1995` (I've requested you for now, since you're also helping with reviewing the expect implementation. You are welcome to delegate this PR, even if it should be a simple review 🙃 )
Only crate root def-ids don't have a parent, and in majority of cases the argument of `DefIdTree::parent` cannot be a crate root.
So we now panic by default in `parent` and introduce a new non-panicing function `opt_parent` for cases where the argument can be a crate root.
Same applies to `local_parent`/`opt_local_parent`.
`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