How to get the *full* custom-language UX in Notebooks?

[metaleap]

TL;DR: I'm not seeing input-cell hovers / completions / etc for our functioning custom-language IntelliSense impl, nor output-cell syntax-coloring with text/x-mylanguageid, what am I missing?

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So my VSCode extension based on vscode-languageclient and a custom backing LSP has all the essentials functioning well: completions, hovers, document-symbols (and workspace symbols search), go-to-definition and list-references.

For our REPL UX, I'm doing a custom NotebookSerializer and NotebookController. Hooked up properly to the notebooks contribution. They do work fine with regards to serializing and executing. BUT, where's all that custom-language-extension UX goodness that I got working so perfectly well in the text-editor tabs?

No completions, hover, go2def etc

In these Notebooks, other than syntax highlighting (for inputs, not outputs), there's none of all that well-working language-extension stuff that's already working in normal text editors for our language. For the input cell: no completions, no hover, no go2def via ctrl+click or F12, nothing! Just syntax coloring.

No output-cell syntax coloring with text/x-mylanguage

With the cell output mimed to text/x-gerbil (the gerbil language ID being properly registered), that output cell isn't syntax-highlighted at all (right now, the output is returned to be the input-cell's value so it's easy to tell: there is no highlighting). But changing it in my NotebookController code to text/x-javascript or text/x-clojure (VSCode builtins) does syntax-color the output cell!

Here it is with text/x-gerbil output-cell mime, while the input cell has language ID gerbil:

How come this fully-properly-registered custom language ID is seemingly second-class in Notebooks, when it's first-class in the normal code text-editor tabs?

Am I missing some boilerplate that's not mentioned in VSCode's Notebooks extension guide?

[rebornix]

@metaleap thanks for your interest in notebook in VS Code! Our documentation is not up to date, will update them later but first let me answer some of your questions

Regarding language features, the notebook cell documents have an unique scheme vscode-notebook-cell, and in your language registration, it's limited to file https://github.com/metaleap/vscode-gerbil-scheme/blob/main/src/lsp.ts#L25C13-L26C1 , that's why none of them works for notebook. You can try add { language: 'gerbil', scheme: 'vscode-notebook-cell' } to the document selector.

For "output-cell syntax coloring", we dropped support for builtin editor output and it's now fully contributed via output renderer https://github.com/rebornix/vscode-code-renderer , if you want to depend on this renderer, we could look into supporting your custom language in this renderer.

[metaleap]

You can try add { language: 'gerbil', scheme: 'vscode-notebook-cell' } to the document selector.

That did the trick! Many thanks @rebornix! 🎉 🚀

Our documentation is not up to date

we dropped support for builtin editor output and it's now fully contributed via output renderer

It's kinda odd though that it just-works when using text/x-clojure but not text/x-gerbil. Does that mean language-grammars from VSCode-owned "internal" extensions are internally "blessed" for output syntax coloring and other grammars are not? Wouldn't it anyway be the same grammar-to-color code, no matter whether the grammar was built-in or extension-provided?

https://github.com/rebornix/vscode-code-renderer , if you want to depend on this renderer,

Not quite grokking this — is that repo of yours a dependency that current VSCode has, or is it some sort of 2.5-years-old "manual fork / extraction" of something buried also in VSCode's own repo? =)

[rebornix]

It's kinda odd though that it just-works when using text/x-clojure but not text/x-gerbil

@metaleap you got me. We have an internal renderer https://github.com/microsoft/vscode/blob/6c907814bfc223e842aa0d82e69a467ce4f76223/extensions/markdown-language-features/package.json#L40-L119 which lists all supported languages (the languages VS Code support). It currently doesn't support languages from external extensions but we could explore relaxing it and supporting rendering mime types which have language grammar provided by extensions.

[metaleap]

but we could explore relaxing it and supporting rendering mime types which have language grammar provided by extensions

That'd be swell, here's hoping the feature proposal issue I just made for this won't drown among the 8k+ other issues 😁

[faubulous]

@metaleap The documentation still stays 'text/x-LANGUAGE_ID for any other built-in or installed languages' which is wrong if I understand you correctly? Would be great if that could be corrected.

https://code.visualstudio.com/api/extension-guides/notebook#output-types