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.
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");
}
}
```
The most recent changelog update 037ddf282b accompanying the 1.52 release added a second "Rust 1.52" section header, with the result that the Rust release announcement https://blog.rust-lang.org/2021/05/06/Rust-1.52.0.html is linking to the "current beta" changelog section for Clippy rather than the stable changelog. I don't know the release process but based on previous changes to this file, I assume the correct thing to do is to mark the topmost section as being for Rust 1.53, not 1.52.
Add lint to check for boolean comparison in assert macro calls
This PR adds a lint to check if an assert macro is using a boolean as "comparison value". For example:
```rust
assert_eq!("a".is_empty(), false);
```
Could be rewritten as:
```rust
assert!(!"a".is_empty());
```
PS: The dev guidelines are amazing. Thanks a lot for writing them!
changelog: Add `bool_assert_comparison` lint
* Added expression check for shared_code_in_if_blocks
* Finishing touches for the shared_code_in_if_blocks lint
* Applying PR suggestions
* Update lints yay
* Moved test into subfolder
Lint: filter(Option::is_some).map(Option::unwrap)
Fixes#6061
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog:
* add new lint for filter(Option::is_some).map(Option::unwrap)
First Rust PR, so I'm sure I've violated some idioms. Happy to change anything.
I'm getting one test failure locally -- a stderr diff for `compile_test`. I'm having a hard time seeing how I could be causing it, so I'm tentatively opening this in the hopes that it's an artifact of my local setup against `rustc`. Hoping it can at least still be reviewed in the meantime.
I'm gathering that since this is a method lint, and `.filter(...).map(...)` is already checked, the means of implementation needs to be a little different, so I didn't exactly follow the setup boilerplate. My way of checking for method calls seems a little too direct (ie, "is the second element of the expression literally the path for `Option::is_some`?"), but it seems like that's how some other lints work, so I went with it. I'm assuming we're not concerned about, eg, closures that just end up equivalent to `Option::is_some` by eta reduction.
Add the from_str_radix_10 lint
changelog: added the new `from_str_radix_10` which sometimes replaces calls to `primitive::from_str_radix` to `str::parse`
This is ready to be merged, although maybe the category should be `pedantic` instead of `style`? I'm not sure where it fits better.
Closes#6713.
New lint: default_numeric_fallback
fixes#6064
r? `@flip1995`
As we discussed in [here](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/Issue.20.236064/near/224647188) and [here](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/Issue.20clippy.236064/near/224746333), I start implementing this lint from the strictest version.
In this PR, I'll allow the below two cases to pass the lint to reduce FPs.
1. Appearances of unsuffixed numeric literals in `Local` if `Local` has a type annotation, for example:
```rust
// Good.
let x: i32 = 1;
// Also good.
let x: (i32, i32) = if cond {
(1, 2)
} else {
(2, 3)
};
```
2. Appearances of unsuffixed numeric literals in args of `Call` or `MethodCall` if corresponding arguments of their signature have concrete types, for example:
```rust
fn foo_mono(x: i32) -> i32 {
x
}
fn foo_poly<T>(t: T) -> t {
t
}
// Good.
let x = foo_mono(13);
// Still bad.
let x: i32 = foo_poly(13);
```
changelog: Added restriction lint: `default_numeric_fallback`
Add new lint `filter_map_identity`
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This commit adds a new lint named filter_map_identity.
This lint is the same as `flat_map_identity` except that it checks for the usage of `filter_map`.
---
Closes#6643
changelog: Added a new lint: `filter_map_identity`
This commit adds a new lint named `filter_map_identity`. This lint is
the same as `flat_map_identity` except that it checks for `filter_map`.
Closes#6643
New Lint: Manual Flatten
This is a draft PR for [Issue 6564](https://github.com/rust-lang/rust-clippy/issues/6564).
r? `@camsteffen`
- \[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`
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: Add new lint [`manual_flatten`] to check for loops over a single `if let` expression with `Result` or `Option`.