needless_borrow: suggest removing several references at a time.

[disconnect3d]

Hey,

It would be nice if Clippy could detect needless references as in here:

fn main() {
    let st = String::from("zomg");
    myfunc(&&&&&st);
}

fn myfunc(param: &str) {
    println!("param: {}", param);
}

The myfunc(&&&&&st); should be myfunc(&st);.

Side note: there is a similar, needless lifetime parameter detecting, that would trigger in e.g. fn myfunc<'a>(param: &'a str)

[matthiaskrgr]

Hi, this is already implemented but you have to opt-in manually (#[warn(clippy::needless_borrow)] )

#[warn(clippy::needless_borrow)]
fn main() {
    let st = String::from("zomg");
    myfunc(&&&&&st);
}

fn myfunc(param: &str) {
    println!("param: {}", param);
}

should make clippy warn about it. :)

[disconnect3d]

@matthiaskrgr is there a way to opt in with a CLI argument? Also, how do I list all linters/detectors?

[disconnect3d]

@matthiaskrgr Also, the suggestion given is not the best one and applying it and re-running cargo clippy will still warn:

➜  refs git:(master) ✗ cargo clippy
    Checking refs v0.1.0 (/Users/dc/playground/rust-2/refs)
warning: this expression borrows a reference that is immediately dereferenced by the compiler
 --> src/main.rs:6:12
  |
6 |     myfunc(&&&&&st);
  |            ^^^^^^^ help: change this to: `&&&&st`
  |
note: lint level defined here
 --> src/main.rs:1:8
  |
1 | #[warn(clippy::needless_borrow)]
  |        ^^^^^^^^^^^^^^^^^^^^^^^
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow

    Finished dev [unoptimized + debuginfo] target(s) in 0.12s

seems like something to be improved

[matthiaskrgr]

cargo clippy -- -Wclippy::needless-borrow should work.

Mhh, looks like the lint only looks at one reference at a time.. 🤔

EDIT: link -> lint

[flip1995]

All lints are listed here: https://rust-lang.github.io/rust-clippy/

Just choose the version of Clippy you're using and it will show you all lints in this version with their documentation. (master ~= nightly)