Don't lint `multiple_inherent_impl` with generic arguments
fixes: #5772
changelog: Treat different generic arguments as different types in `multiple_inherent_impl`
Remove powi, "square can be computed more efficiently"
powi(2) produces exactly the same native code as x * x
powi was part of the [`suboptimal_flops`] lint
fixes#7058
changelog: Remove powi [`suboptimal_flops`], "square can be computed more efficiently"
Add `needless_bitwise_bool` lint
fixes#6827fixes#1594
changelog: Add ``[`needless_bitwise_bool`]`` lint
Creates a new `bitwise_bool` lint to convert `x & y` to `x && y` when both `x` and `y` are booleans. I also had to adjust thh `needless_bool` lint slightly, and fix a couple failing dogfood tests. I made it a correctness lint as per flip1995's comment [here](https://github.com/rust-lang/rust-clippy/pull/3385#issuecomment-434715723), from a previous WIP attempt at this lint.
Fix FPs about generic args
Fix 2 false positives in [`use_self`] and [`useless_conversion`] lints, by taking into account generic args and comparing them.
Fixes: #7205Fixes: #7206
changelog: Fix FPs about generic args in [`use_self`] and [`useless_conversion`] lints
New lint: `unused_async`
changelog: Adds a lint, `unused_async`, which checks for async functions with no await statements
`unused_async` is a lint that reduces code smell and overhead by encouraging async functions to be refactored into synchronous functions.
Fixes#7176
### Examples
```rust
async fn get_random_number() -> i64 {
4 // Chosen by fair dice roll. Guaranteed to be random.
}
```
Could be written as:
```rust
fn get_random_number() -> i64 {
4 // Chosen by fair dice roll. Guaranteed to be random.
}
```
Something like this, however, should **not** be caught by clippy:
```rust
#[async_trait]
trait AsyncTrait {
async fn foo();
}
struct Bar;
#[async_trait]
impl AsyncTrait for Bar {
async fn foo() {
println!("bar");
}
}
```
Stop linting `else if let` pattern in [`option_if_let_else`] lint
For readability concerns, it is counterproductive to lint `else if let` pattern.
Unfortunately the suggested code is much less readable.
Fixes: #7006
changelog: stop linting `else if let` pattern in [`option_if_let_else`] lint
Add `cargo collect-metadata` as an cargo alias for the metadata collection lint
This PR adds a new alias to run the metadata collection monster on `clippy_lints`. I'm currently using it to create the `metadata_collection.json` file and I plan to use it in the `deply.sh` script. Having it as a new alias enables us to simply use:
```sh
cargo collect-metadata
```
It sometimes requires running `cargo clean` before collecting the metadata due to caching. I'm still debating if I should include a cargo clean as part of the `run_metadata_collection_lint` test or not. Input on this would be greatly appreciated 🙃
That's it, just a small change that can be reviewed and merged in parallel to #7214.
---
See: #7172 for the full metadata collection to-do list or to suggest a new feature in connection to it.
---
changelog: none
r? `@flip1995` btw. feel free to pass these PRs one to other team members as well if you want.
`needless_collect` enhancements
fixes#7164
changelog: `needless_collect`: For `BTreeMap` and `HashMap` lint only `is_empty`, as `len` might produce different results than iter's `count`
changelog: `needless_collect`: Lint `LinkedList` and `BinaryHeap` in direct usage case as well
Trigger [`wrong_self_convention`] only if it has implicit self
Lint [`wrong_self_convention`] only if the impl or trait has `self` _per sé_.
Fixes: #7179
changelog: trigger [`wrong_self_convention`] only if it has implicit self
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.
* Suggest `&mut iter` when the iterator is used after the loop.
* Suggest `&mut iter` when the iterator is a field in a struct.
* Don't lint when the iterator is a field in a struct, and the struct is
used in the loop.
* Lint when the loop is nested in another loop, but suggest `&mut iter`
unless the iterator is from a local declared inside the loop.
Fix needless_quesiton_mark false positive
changelog: Fix [`needless_question_mark`] false positive where the inner value is implicity dereferenced by the question mark.
Fixes#7107
Handle write!(buf, "\n") case better
Make `write!(buf, "\n")` suggest `writeln!(buf)` by removing
the trailing comma from `writeln!(buf, )`.
changelog: [`write_with_newline`] suggestion on only "\n" improved
Make `write!(buf, "\n")` suggest `writeln!(buf)` by removing
the trailing comma from `writeln!(buf, )`.
changelog: [`write_with_newline`] suggestion on only "\n" improved
It relaxes rules for `to_*` variant, so it doesn't lint in trait definitions
and implementations anymore.
Although, non-`Copy` type implementing trait's `to_*` method taking
`self` feels not good (consumes ownership, so should be rather named `into_`), it would be better if this case was a pedantic lint (allow-by-default) instead.
Refactor: arrange lints in misc_early module
This PR arranges misc_early lints so that they can be accessed more easily.
Basically, I refactored them following the instruction described in #6680.
cc: `@Y-Nak,` `@flip1995,` `@magurotuna`
changelog: Move lints in misc_early module into their own modules.
Fix stack overflow issue in `redundant_pattern_matching`
Fixes#7169
~~cc `@Jarcho` Since tomorrow is release day and we need to get this also fixed in beta, I'll just revert the PR instead of looking into the root issue. Your changes are good, so if you have an idea what could cause this stack overflow and know how to fix it, please open a PR that reverts this revert with a fix.~~
r? `@llogiq`
changelog: none (fixes stack overflow, but this was introduced in this release cycle)
needless_collect: Lint cases with type annotations for indirect usage and recognize `BinaryHeap`
fixes#7110
changelog: needless_collect: Lint cases with type annotations for indirect usage and recognize `BinaryHeap`.
Producing a good suggestion for this lint is already hard when no macros
are involved. With macros the lint message and the suggestion are just
confusing. Since both, producing a good suggestion and figuring out if
this pattern can be re-written inside a macro is nearly impossible, just
bail out.
Update BARE_TRAIT_OBJECT and ELLIPSIS_INCLUSIVE_RANGE_PATTERNS to errors in Rust 2021
This addresses https://github.com/rust-lang/rust/pull/81244 by updating two lints to errors in the Rust 2021 edition.
r? `@estebank`
[single_char_pattern] add strip_prefix and strip_suffix
Title says it all. Adjusted ui tests.
I added the second commit in case you don't like that I moved that table into `single_char_pattern.rs` directly. I don't see any reason why it shouldn't be in that file. It isn't used anywhere else.
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: add strip_prefix and strip_suffix to single_char_pattern lint
while_immutable_cond: check condition for mutation
This fixes#6689 by also checking the bindings mutated in the condition, whereas it was previously only checked in the loop body.
---
changelog: Fix FP in [`while_immutable_cond`] where mutation in the loop variable wasn't picked up.
`implicit_return` improvements
fixes: #6940
changelog: Fix `implicit_return` suggestion for async functions
changelog: Improve `implicit_return` suggestions when returning the result of a macro
changelog: Check for `break` expressions inside a loop which are then implicitly returned
changelog: Allow all diverging functions in `implicit_return`, not just panic functions
Implement `x.py test src/tools/clippy --bless`
- Add clippy_dev to the rust workspace
Before, it would give an error that it wasn't either included or
excluded from the workspace:
```
error: current package believes it's in a workspace when it's not:
current: /home/joshua/rustc/src/tools/clippy/clippy_dev/Cargo.toml
workspace: /home/joshua/rustc/Cargo.toml
this may be fixable by adding `src/tools/clippy/clippy_dev` to the `workspace.members` array of the manifest located at: /home/joshua/rustc/Cargo.toml
Alternatively, to keep it out of the workspace, add the package to the `workspace.exclude` array, or add an empty `[workspace]` table to the package's manifest.
```
- Change clippy's copy of compiletest not to special-case
rust-lang/rust. Using OUT_DIR confused `clippy_dev` and it couldn't find
the test outputs. This is one of the reasons why `cargo dev bless` used
to silently do nothing (the others were that `CARGO_TARGET_DIR` and
`PROFILE` weren't set appropriately).
- Run clippy_dev on test failure
I tested this by removing a couple lines from a stderr file, and they
were correctly replaced.
- Fix clippy_dev warnings
- Add clippy_dev to the rust workspace
Before, it would give an error that it wasn't either included or
excluded from the workspace:
```
error: current package believes it's in a workspace when it's not:
current: /home/joshua/rustc/src/tools/clippy/clippy_dev/Cargo.toml
workspace: /home/joshua/rustc/Cargo.toml
this may be fixable by adding `src/tools/clippy/clippy_dev` to the `workspace.members` array of the manifest located at: /home/joshua/rustc/Cargo.toml
Alternatively, to keep it out of the workspace, add the package to the `workspace.exclude` array, or add an empty `[workspace]` table to the package's manifest.
```
- Change clippy's copy of compiletest not to special-case
rust-lang/rust. Using OUT_DIR confused `clippy_dev` and it couldn't find
the test outputs. This is one of the reasons why `cargo dev bless` used
to silently do nothing (the others were that `CARGO_TARGET_DIR` and
`PROFILE` weren't set appropriately).
- Run clippy_dev on test failure
I tested this by removing a couple lines from a stderr file, and they
were correctly replaced.
- Fix clippy_dev warnings
Fix FN in `iter_cloned_collect` with a large array
fixes#6808
changelog: Fix FN in `iter_cloned_collect` with a large array
I spotted that [is_iterable_array](a362a4d1d0/clippy_lints/src/loops/explicit_iter_loop.rs (L67-L75)) function that `explicit_iter_loop` lint is using only works for array sizes <= 32.
There is this comment:
> IntoIterator is currently only implemented for array sizes <= 32 in rustc
I'm a bit confused, because I read that [IntoIterator for arrays](https://doc.rust-lang.org/src/core/array/mod.rs.html#194-201) with const generic `N` is stable since = "1.0.0". Although Const Generics MVP were stabilized in Rust 1.51.
Should I set MSRV for the current change? I will try to test with older compilers soon.
manual_unwrap_or: fix invalid code suggestion, due to macro expansion
fixes#6965
changelog: fix invalid code suggestion in `manual_unwrap_or` lint, due to macro expansion
`single_component_path_imports`: ignore `pub(crate) use some_macro;`
Fixes#7106
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: Ignore exporting a macro within a crate using `pub(crate) use some_macro;` for [`single_component_path_imports`]
Unused io amount detects `.read().ok()?`
fixes#7096
changelog: unused_io_amount now detect expertion like `.read().ok()?`, `.read().or_else(|err| ...)?` and similar expressions.
Better suggestions when returning macro calls.
Suggest changeing all the break expressions in a loop, not just the final statement.
Don't lint divergent functions.
Don't suggest returning the result of any divergent fuction.
