clippy::match_wild_err_arm: `Err(_)` matches all errors

What you see

warning: `Err(_)` matches all errors
 --> main.rs:6:5
  |
6 |     Err(_) => panic!("err"),
  |     ^^^^^^
  |
  = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
  = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#match_wild_err_arm
  = note: `-W clippy::match-wild-err-arm` implied by `-W clippy::pedantic`

Real output of Clippy 0.1.99 (Rust 1.99) on the example below. Names and line numbers in yours will differ.

Does it matter?

It is generally a bad practice, similar to catching all exceptions in java with catch(Exception)

Stricter lints with some false positives. Off by default; opt in with clippy::pedantic.

How to fix it

Clippy does not fix this one automatically. Change the code by hand:

Flagged

let x: Result<i32, &str> = Ok(3);
match x {
    Ok(_) => println!("ok"),
    Err(_) => panic!("err"),
}

Turn it off, or on

It is off by default. To use it, set it to warn or deny:

[lints.clippy]
match_wild_err_arm = "warn"

#![warn(clippy::match_wild_err_arm)]

cargo clippy -- -W clippy::match-wild-err-arm

The [lints] table needs Rust 1.74 or newer. In a workspace, put it under [workspace.lints.clippy] and add [lints] workspace = true to each member.