Assist: reorder fields

[matklad]

This assist should be applicable to record literals and patterns, and should reorder fields in the same order as in the definition. Ie, it should be able to cleanup this:

[Veetaha]

I wonder if there is any caveat in the order of evaluation of record literal fields initializers

[matklad]

Assists are not guaranteed to preserve semantics.

[JoshMcguigan]

I think this could get tricky:

struct Foo {
    a: String,
    b: String,
}

impl Foo {
    fn new() -> Self {
        let s = String::new();
        Self {
            b: s.clone(),
            a: s,
        }
    }
}

I'd think the output of an assist should always compile at least?

[matklad]

I'd think the output of an assist should always compile at least?

Not necessary, assist is just a tool that applies some syntactic transformation which is helpful, it doesn't need to be complete or "correct". For example, in fill match arms, we deliberately use {} and not todo!() as a placeholder, because {} is easier to delete.

The goal of assist is to be useful, and in your example I would be totally willing to apply the assist and move the clone call manually afterwards.

[geoffreycopin]

Hi,
First-time contributor here. I'd love to give this a try !

[eminence]

I believe this issue can be closed, as it was implemented in #3925