monaco.languages.typescript is undefined

[wangtuyao]

Hi,

I am using monaco-languageclient to connect to a typescript language server backend service. The workspace path points to a typescript project, and it is successful. IntelliSense is also working properly.

However, I am unable to use monaco.languages.typescript.javascriptDefaults.addExtraLib to add some extra in-memory created libraries because monaco.languages.typescript is undefined.

I noticed in #735 that it requires import @codingame/monaco-vscode-standalone-typescript-language-features. After trying that, I found that monaco.languages.typescript.javascriptDefaults.addExtraLib could be successfully called, but another error appeared :

errors.js:10 Uncaught Error: Unexpected usage

Error: Unexpected usage
    at _EditorSimpleWorker.loadForeignModule (editorSimpleWorker.js:583:33)
    at webWorker.js:29:30
    at async tsMode.js:86:16
    at async WorkerManager.getLanguageServiceWorker (tsMode.js:92:20)
    at async DiagnosticsAdapter._doValidate (tsMode.js:377:20)
    at _EditorSimpleWorker.loadForeignModule (editorSimpleWorker.js:583:33)
    at webWorker.js:29:30
    at async tsMode.js:86:16
    at async WorkerManager.getLanguageServiceWorker (tsMode.js:92:20)
    at async DiagnosticsAdapter._doValidate (tsMode.js:377:20)
    at errors.js:10:29

My question is:

1. How can be resolved this error?
2. Since my typescript language client workspace points to a typescript project (in order to obtain IntelliSense for this project), but I also use monaco.languages.typescript.javascriptDefaults.addExtraLib to add extra libraries in memory, how does Monaco's IntelliSense behave in this case? Does it prioritize the content from monaco.languages.typescript.javascriptDefaults.addExtraLib or the language client? If there are conflicting types with the same name, how does IntelliSense handle the suggestions?

Thinks.

[kaisalmen]

Hi @wangtuyao which typescript language server backend service do you use? If you use a language server you can use the syntax highlighting in the front-end, but you should not use the standalone worker services for TypeScript that monaco-editor provides. Extra library loading should be handle by the language server in your scenario as far as I can tell.

[wangtuyao]

@kaisalmen Thinks for reply.

If you use a language server you can use the syntax highlighting in the front-end, but you should not use the standalone worker services for TypeScript that monaco-editor provides

Does this mean that once I use typescript-language-server to get syntax highlighting and IntelliSense on brower, I won't be able to use standalone worker services e.g. monaco.languages.typescript.javascriptDefaults.addExtraLib to add some extra lib in memory?

[kaisalmen]

Does this mean that once I use typescript-language-server to get syntax highlighting and IntelliSense on browser, I won't be able to use standalone worker services

@wangtuyao I don't know. How do they configure that in VSCode? Do they have examples for that?

[kaisalmen]

Btw, have you checked https://github.com/TypeFox/monaco-languageclient/blob/main/packages/examples/src/ts/wrapperTs.ts This example makes uses of VSCode typescript support and runs it in a worker. Maybe this is can be more helpful for you use case? It does not require to have a backend.

[CGNonofr]

monaco.languages.typescript.javascriptDefaults.addExtraLib is only used to configure the monaco typescript worker

There are 3 ways to provide typescript intellisense:

• using the monaco worker: you can configure it using the monaco.languages.typescript namespace
• using the VSCode default extension: you can configure it by creating a tsconfig/jsconfig file in the project in the client virtual filesystem
• using a remote typescript language server, which can be configured directly from the server

You shouldn't use more than one or you'll have duplicated suggestions

I'm not sure why you may want to call addExtraLib if you use a remote language server, you can install types just as you would do in any project

[wangtuyao]

@CGNonofr @kaisalmen thinks. got it . In our case we should use monaco worker.