tsserver: saveto command should also save inferred ("virtual") tsconfig

Search Terms

tsserver saveto tsconfig

Suggestion

I want to store the content of the "virtual" tsconfig.json that is used by the ts server.

The Saveto comand stores source files. One might aswell allow to store the tsconfig.

Use Cases

I work on a code analysis component. Before I started to implement it, I created a vscode project to adjust settings and declaration files. Once everything worked as expected, I implemented the component that communicates with the tsserver. My implementation does not use a "physical" tsconfig. It relies on the tsconfig the server infers, based on commandline parameters and CompilerOptionsForInferredProjects.

My component updates ts and d.ts files in this virtual project based on user input. This is where problems might appear which are hard to debug within my limited "client".

For debugging and suport purposes I want to take a "snapshot" of the files the tsserver uses, and use vscode for further analysis.

Examples

The request sent to the server would look something like this:

{"arguments":{"tmpfile":"C:\\TEMP\\tsconfig.json","file":"tsconfig.json"},"command":"saveto","seq":0,"type":"request"}

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

Start with the Saveto command in src/server/protocol.ts and review CompilerOptionsForInferredProjects, both named in the issue. Trace how inferred projects and their virtual tsconfig are represented before determining how a saveto request could snapshot one. Done means the command can store the inferred tsconfig for the described request without changing existing source-file behavior.