Activate language features solely on file open (in theia IDE)

[chbo123456]

Hi,

is it possible to active the language features only to the file(s) which are currently opened by the IDE? Usually the whole workspace is parsed on extension activation and if the workspace contains many files, this makes the (theia) IDE pretty slow. If yes, can this be made configurable in a "lunch.json" file or so?

Thanks!

[msujew]

Hey @chbo123456,

you will effectively need to build a toggle for this behavior:

langium/packages/langium/src/workspace/workspace-manager.ts

Lines 80 to 83 in 8a53552

	await Promise.all(
	folders.map(wf => [wf, this.getRootFolder(wf)] as [WorkspaceFolder, URI])
	.map(async entry => this.traverseFolder(...entry, fileExtensions, collector))
	);

You could maybe create a config format for your language (similar to tsconfig.json) and create an option in there that decides whether or not to load the whole workspace. Even better, it could contain a setting that limits the search pattern using something like glob. Since the launch.json has no influence on runtime behavior of the IDE (it is mainly used for debugging), placing the toggle there would be not advisable.

[chbo123456]

@msujew Do you mean to override the traverseFolder method?

[msujew]

Either traverseFolder or the whole initializeWorkspace method if needed. It depends on how much you actually need to modify the behavior.

[chbo123456]

Thanks!