How to support snippets on code actions expansions.

[emi2k01]

If I have the following code:

pub struct Foo;

impl std::fmt::Display for Foo {
}

fn main() {
}

and I use the code action Implement missing members, the generated code is:

pub struct Foo;

impl std::fmt::Display for Foo {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        ${0:todo!()} // I want my cursor to move here.
    }
}

fn main() {
}

I am using vim-vsnip for regular snippets.

I don't know if this is in the scope of rust-tools or not.

[simrat39]

Should be possible if there's some exported api in the completion plugins (nvim-cmp / compe)

[simrat39]

This all really depends if a snippet plugin adds support for this, because its out of scope for this plugin

[emi2k01]

It makes sense. Should this issue be closed? I'll keep an eye on the vim-vsnip issue.

Thanks!

[simrat39]

Let's keep it open for now

[hrsh7th]

1. The TextEdit related implementations are implemented in nvim core (vim.lsp.util.apply_text_edits).
2. The Snippet feature implemented in vim-vsnip or LuaSnip.
3. The CompleteItem handling implemented in nvim-cmp
4. The rust-analyzer related features implemented in rust-tools.nvim

So I think it should be implemented in rust-tools.nvim.

But I also think it is too harder because snippet and textEdit both are complex implementation.

[hrsh7th]

I think rust-tools.nvim should get the snippet expansion function as a configuration item. (nvim-cmp does it).

And You can override the vim.lsp.util.apply_text_edits function. (I don't like this solution but I have no another idea...

[sharksforarms]

I would expect it to work like this where you can configure how the snippet gets expanded: https://github.com/hrsh7th/nvim-cmp/blob/main/README.md?plain=1#L70-L81

[simrat39]

I would expect it to work like this where you can configure how the snippet gets expanded: https://github.com/hrsh7th/nvim-cmp/blob/main/README.md?plain=1#L70-L81

Yes I would prefer this as well, but the snippet extenstions would have to actually support the SnippetTextEdits that are given by rust analyzer which aren't supported by any afaik

[simrat39]

I think rust-tools.nvim should get the snippet expansion function as a configuration item. (nvim-cmp does it).

And You can override the vim.lsp.util.apply_text_edits function. (I don't like this solution but I have no another idea...

Yep we plan to do it if snippet plugins are down to add support

[ModProg]

I don't know if this is related, but when using rust_analyzer with lspconfig without rust-tools I get this expansion on "fill match arms":

match c {
    Test::A(_) => todo!(),
    Test::B(_) => todo!(),
    Test::C { a, b, c } => todo!(),
}

But with rust-tools this happens:

match c {
    Test::A(${0:_}) => todo!(),
    Test::B(_) => todo!(),
    Test::C { a, b, c } => todo!(),
}

Maybe it is possible to have the lspconfig expansion for now, until the cursor move is implemented, as that code is at least compilable?

[Freyskeyd]

I agree for now I can't really use rust-tools for that :s
Can we have an option to switch from one another ?

[simrat39]

Fixed with 0190496

Edit: Don't think we'll ever support actual snippets, but now we replace the placeholders with the defaults so its valid rust code.