match_single_binding: Fix invalid suggestion when match scrutinee has side effects
fixes#7094
changelog: `match_single_binding`: Fix invalid suggestion when match scrutinee has side effects
---
`Expr::can_have_side_effects` is used to determine the scrutinee has side effects, while this method is a little bit conservative for our use case. But I'd like to use it to avoid reimplementation of the method and too much heuristics. If you think this is problematic, then I'll implement a custom visitor to address it.
thread 'rustc' panicked at 'index out of bounds: the len is 0 but the index is 0', src/tools/clippy/clippy_lints/src/matches.rs:1595:53
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
I don't have a minimised testcase because I don't have time to reduce libstd down to a few lines right now.
Add `cloned_instead_of_copied` lint
Don't go cloning all willy-nilly.
Featuring a new `get_iterator_item_ty` util!
changelog: Add cloned_instead_of_copied lint
Closes#3870
Fix: redundant_pattern_matching drop order
Fixes#5746
A note about the change in drop order is added when the scrutinee (or any temporary in the expression) isn't known to be safe to drop in any order (i.e. doesn't implement the `Drop` trait, or contain such a type). There is a whitelist for some `std` types, but it's incomplete. Currently just `Vec<_>`, `Box<_>`, `Rc<_>` and `Arc<_>`, but only if the contained type is also safe to drop in any order.
Another lint for when the drop order changes could be added as allowed by default, but the drop order requirement is pretty subtle in this case. I think the note added to the lint should be enough to make someone think before applying the change.
changelog: Added a note to `redundant_pattern_matching` when the change in drop order might matter
Deprecate `intrinsics::drop_in_place` and `collections::Bound`, which accidentally weren't deprecated
Fixes#82080.
I've taken the liberty of updating the `since` values to 1.52, since an unobservable deprecation isn't much of a deprecation (even the detailed release notes never bothered to mention these deprecations).
As mentioned in the issue I'm *pretty* sure that using a type alias for `Bound` is semantically equivalent to the re-export; [the reference implies](https://doc.rust-lang.org/reference/items/type-aliases.html) that type aliases only observably differ from types when used on unit structs or tuple structs, whereas `Bound` is an enum.
Don't lint on `Result` and `Option` types.
Considers `or` patterns.
Considers variants prefixed with `Self`
Suggestions will try to find a common prefix rather than just using the full path
Do not lint when range is completely included into another one
This fix has been developed following this [comment](https://github.com/rust-lang/rust-clippy/issues/5986#issuecomment-703313548).
So this will be linted:
```
|----------|
|-----------|
```
Now this won't be linted:
```
|---|
|--------------------|
```
and this will still lint:
```
|--------|
|--------------|
```
Fixes: #5986
changelog: Fix FPs in match_overlapping_arm, when first arm is completely included in second arm