LSP: fix(diagnostics), ensure immediate updates for opened dependent files on change

[adam2am]

Hey, quick fix for my previous refactor

The Problem (Bug)

Currently, if a user modifies an exported member in export.civet, any other open file (import.civet) that imports that member does not instantly receive updated diagnostic errors even when files are open in editor. It appears only after direct edit in the import.civet

How to Replicate

1. Create two files:

   • export.civet:

     abc := 321
     export {abc}
     

   • import.civet:

     import {abc} from './export.civet'
     

2. Open both files in the editor. Observe that there are no errors.

3. In export.civet, change the exported variable name:

   // From
   abc := 321
   export {abc}
   
   // To
   a := 321
   export {a}
   

4. Observe (The Bug): Switch to the import.civet file. No diagnostic error is shown. The linter is silent, even though the import of abc is now invalid.

5. Expected Behavior: The moment export.civet is saved or changed, an error should immediately appear in import.civet, highlighting that abc is not an exported member.

The Solution

The root cause of this bug was a path mismatch within the updateProjectDiagnostics function. The function iterates through all files in the TypeScript program using program.getSourceFiles().

The fix is to use service.getSourceFileName(sourceFile.fileName). This method correctly resolves the path known by the TypeScript service back to its original source file path. This ensures we can reliably find the corresponding open document in our documents map and push the updated diagnostics to the editor immediately after a dependency changes.

Happy to hear any thoughts, its a small, but important fix imo

[adam2am]

By the way, I think

if (doc) {
      await updateDiagnosticsForDoc(doc, service);

also have a room for improvement. But this not as urgent as this fix