rust-lang / rust-lang/rust-clippy
unnecessary_wraps: ignore functions that return type aliases?
Open
Nobody has claimed this yet.
C-bug
I-false-positive
S-needs-discussion
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Description
type ThatsOk = Option<i32>;
fn new_ok() -> ThatsOk {
Some(3)
}
fn main() {
let _ = new_ok();
}
warning: this function's return value is unnecessarily wrapped by `Option`
--> src/main.rs:3:1
|
3 | / fn new_ok() -> ThatsOk {
4 | | Some(3)
5 | | }
| |_^
|
= note: `#[warn(clippy::unnecessary_wraps)]` on by default
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_wraps
help: remove `Option` from the return type...
|
3 | fn new_ok() -> i32 {
| ^^^
help: ...and change the returning expressions
|
4 | 3
|
IMO the lint should not trigger here because we use a newtype type aliases here and making code work without them may take quite some effort which goes beyond removing a match or an .unwrap() in real world examples.
Thoughts?
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the Rust example and tracing the unnecessary_wraps lint's handling of aliased return types. Done means the lint no longer warns for the shown type-alias case, with coverage for that behavior.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- tooling
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100