Updates `needless_collect` to lint for collecting into a method or
function argument thats taking an `IntoIterator` (for example `extend`).
Every `Iterator` trivially implements `IntoIterator` and colleting it
only causes an unnecessary allocation.
[arithmetic_side_effects] Consider referenced allowed or hard-coded types
Fix#10767
```
changelog: [`arithmetic_side_effects`]: Do not fire when dealing with allowed or hard-coded types that are referenced.
```
fix: warn on empty line outer AttrKind::DocComment
changelog: [`empty_line_after_doc_comments`]: add lint for checking empty lines after rustdoc comments.
Fixes: #10395
add lint `manual_next_back`
changelog: [`manual_next_back`]: checks for manual reverse iteration (`.rev().next()`) of a `DoubleEndedIterator`
fixes#10274
Add configuration options to `--explain`
This PR rearranges some modules, taking `metadata_collector` out of `internal_lints` and making public just the necessary functions for `explain()` to use.
The output looks something like this:
```sh
$ cargo run --bin cargo-clippy --manifest-path ../rust-clippy/Cargo.toml -- --explain cognitive_complexity
### What it does
Checks for methods with high cognitive complexity.
### Why is this bad?
Methods of high cognitive complexity tend to be hard to
both read and maintain. Also LLVM will tend to optimize small methods better.
### Known problems
Sometimes it's hard to find a way to reduce the
complexity.
### Example
You'll see it when you get the warning.
========================================
Configuration for clippy::cognitive_complexity:
- cognitive-complexity-threshold: The maximum cognitive complexity a function can have (default: 25)
```
Fixes#9990
r? `@xFrednet`
---
changelog: Docs: `cargo clippy --explain LINT` now shows possible configuration options for the explained lint
[#10751](https://github.com/rust-lang/rust-clippy/pull/10751)
<!-- changelog_checked -->
Extend `trait_duplication_in_bounds` to cover trait objects
This PR extends `trait_duplication_in_bounds` to cover trait objects.
Currently,
```rs
fn foo(_a: &(dyn Any + Send + Send)) {}
```
generates no warnings. With this PR, it will complain about a duplicate trait and can remove it
Moved from rust-lang/rust#110991
changelog: [`trait_duplication_in_bounds`]: warn on duplicate trait object constraints
