Hi there! I’m working on semantic coloring support for C++, and have a couple of questions.
Semantic coloring is a proposed LSP feature with client-side support in Theia. It works by having the server send token ranges along with “TextMate scopes” which identify the coloring to be used for each token.
As far as I can tell, the colors are defined in theme files such as
packages/monaco/data/monaco-themes/vscode/dark_vs.json. For example, here that theme file associates the scope
“meta.preprocessor” with a particular foreground color.
Now, I have two questions:
If I would like the C++ plugin to add support for some C+±specific scopes, and associated default colors, how can I do that?
If then I as a user of the C++ plugin would like to customize the color for a particular scope to something other than the default, how can I do that?
[original thread by Nathan Ridge]
@nridge, please note the following limitations:
@kittaakos, thanks for letting me know about that.
Do I understand correctly that these issues mean that the semantic highlighting feature does not currently work (or does not work reliably) until the plan described in this comment is implemented?
I don’t fully understand the relationship between Theia and VSCode, and so I don’t know to what extent problems and solutions carry over from one to the other, but I’ll note that vscode-cquery has a fully functional semantic highlighting feature (using a custom LSP protocol extension, not your proposed one). This is the API it uses to apply the highlightings. Does that help us at all?
@svenefftinge, thanks for the pointer. However, I’m a bit confused as this talks about using
editor.tokenColorCustomizations. That is indeed how I do it in VSCode, but Theia doesn’t seem to recognize it.
However, I’m a bit confused as this talks about using editor.tokenColorCustomizations. That is indeed how I do it in VSCode, but Theia doesn’t seem to recognize it.
@nridge Theia is capable of running VS Code extensions. Could you try to run your VS Code extensions? If somethign does not work, we should file a bug and look into it. On how to test: https://github.com/theia-ide/theia/wiki/Testing-VS-Code-extensions
Looking at source code of vscode-cquery, it seems that all used vscode APIs are alredy implemented, except 2 commands
@anton-kosyakov, I’m not looking to port vscode-cquery to Theia (it’s a plugin for interfacing with the “cquery” language server whose development has largely been abandoned in favour of clangd). I was just pointing out that it successfully implements semantic coloring. I see that it uses the
TextEditor.setDecorations() API. Do I understand correctly, that we can now use this API in Theia? @kittaakos, would our ability to use this API (instead of
deltaDecorations(), I guess?) resolve the issue you mentioned?
You can run VS Code extensions using this API in Theia, for instance power-mode ext uses it: https://github.com/theia-ide/theia/pull/4827
Ok, I see. The place where we’d want to use it, though, is the shared (cross-language) client implementation of an LSP feature. Is that allowed to be in a VSCode plugin?
Following up on another subtread: @svenefftinge, I’ve had a look at https://code.visualstudio.com/api/extension-guides/color-theme#syntax-colors, and I’m still a bit confused about how it’s applicable to the problem of a Theia plugin extending a color theme. Could you perhaps point me to an existing Theia plugin which extends a color theme?
This API is not part of LSP, so if you want to build a part which is reusable for different editors, not only for IDEs supporting VS Code extensions then it is not a way to go
I’m not looking to “build a part which is reusable for different editors”, I’m looking to implement a particular LSP message (
textDocument/semanticHighlighting) in a particular editor (Theia), or rather fix an issue in its existing implementation.