[display] dynamically update the syntax cache

[Gama11]

The completion server has a syntax cache for things like toplevel completion. It is initialized once on startup with server/readClassPaths. The problem is that after this point, it is never updated again.

Here's an example with a newly created Test type, which doesn't show up in completion and thus can't be auto-imported. It only shows up after restarting the language server.

Conversely, Test will still show up after it has been deleted:

To avoid these issues, Haxe needs to update its syntax cache dynamically when types are added or removed. We probably also need some new methods (server/moduleCreated / server/moduleDeleted?) to inform Haxe about changes based on file watcher events (similar to the server/invalidate we already have).

[Simn]

This requires some design. Mostly because it's not even clear if a deleted/added file is even relevant with regards to class path resolution.

Actually, I don't think we'd need moduleDeleted because that should be the same as invalidate, right?

[Gama11]

Hm, right, I guess the compiler would notice that the file doesn't exist anymore when invalidating a deleted file...

[Simn]

I think the most straightforward way to implement moduleAdded is to invalidate all types (not just modules) that live in a module with the same name. It's a bit brute-force but I struggle to see how we would handle type resolution in the general case otherwise.

[djaonourside]

Guys, what's the issue status? I'm asking because suppose it's rather critical and basic aspect of editor language support.

[nadako]

Would be nice to have for 4.0 indeed, as it's pretty annoying when working in VS Code.

[Simn]

I'm willing to work on this, but I can't do much on the vshaxe side because it only compiles for @Gama11 these days.

I'll try to construct a failing test case for this

[Simn]

I have added server/moduleCreated and the test passes now. There's no additional invalidation going on yet, I'll have to check if that's the right thing to do. Now vshaxe needs an update.