Filter out variables on Outline view

[aldonogueira]

The outline view would be more useful if there were a way to filter out the variables. It seems most of the times developers are interested in functions, traits and structs, but the variables make them sparse.

I don't know the proper way to implement this behaviour though.

• A new checkbox in atom-ide-rust config that filter out variables in outline view
• Wait for Filtering/Sorting of Outline View on atom-ide-ui be implemented
• Combination of informing proper hierarchy to outline view and Collapse Functions by Default in Outline-View on atom-ide-ui

[alexheretic]

Currently ide-rust totally relies on upstream atom-languageclient & atom-ide-ui for outlines. I think, in general, adding new functionality upstream and then configuring it best for rust here makes sense.

At the same time if you want to raise a PR to add a filter option for variables in the outline, I'd probably accept it as we can always drop the config when that functionality appears upstream.

[aldonogueira]

The interaction between components are way more complex than I thought. I'm not sure which piece of software should be modified to properly show hierarchy of items in the outline. I'll take a look at it again over the weekend

[aldonogueira]

It looks there is already an issue to remove local variables from the RLS. I guess they may be useful in other languages, but in Rust's outline they seem unnecessary

[aldonogueira]

I made a PR in RLS to remove local variables, but people thought the best thing to do was to reclassify the symbols so the local variables could be filtered later. Where could local variables be filtered?

Notice although we Rust users don't want to see local variables in the outline view, Javascript users may want them there. It could be useful to have local variables in the symbol search as well.

[alexheretic]

It seems that the outline in atom uses the documentSymbol containerName to build a parent/child relation in the outline view. Rls doesn't supply this so it's totally flat. I'm not sure how useful this outline is without the parent/child thing.

For example this is how it looks for ide-typescript

I haven't been following the discussion too closely though, do you know why we aren't implementing containerName usage in Rls?

But if you want to try filtering client-side, override atom-languageclient's behaviour with something like this in ide-rust

// index.js
class RustLanguageClient extends AutoLanguageClient {
  ...
  provideOutlines() {
    let provide = super.provideOutlines()
    let superOutline = provide.getOutline

    provide.getOutline = async (...args) => {
      let outline = await superOutline.apply(this, args)
      outline.outlineTrees = outline.outlineTrees
        .filter(o => o.icon !== "type-variable")
      return outline
    }

    return provide
  }
}

It looks to me like the outline isn't very useful with or without the filtering.

[aldonogueira]

Even though the outline view would be more useful with hierarchy, the items are in the correct order. I've seen the outline with no local variables when I tested my version of RLS. It's much better than what we have now.

I know there are some difficulties determining proper hierarchy of Rust elements, but the last entry on that issue is from 23 Nov 2016. :( It looks like, since vscode doesn't have an outline view, the people that develops RLS don't think of this feature as an priority.

Thanks for the code sample. I'll try filtering with my version of RLS.

[aldonogueira]

What happened to the icons in outline view? I have just checked my Atom and they are gone here too for Java, Rust and Javascript :(

[aldonogueira]

Nevermind. I found it: facebookarchive/atom-ide-ui#175