List all workspace symbols when an empty query comes in

[groig]

According to the specification the workspace symbols provider should
accept an empty query string and return all the symbols in that case

https://microsoft.github.io/language-server-protocol/specification#workspace_symbol

/**
 * The parameters of a Workspace Symbol Request.
 */
interface WorkspaceSymbolParams extends WorkDoneProgressParams,
	PartialResultParams {
	/**
	 * A query string to filter symbols by. Clients may send an empty
	 * string here to request all symbols.
	 */
	query: string;
}

The test is quite primitive as I am an Elixir beginner. If this feature is of interest I would appreciate some help improving them.

[lukaszsamson]

@groig Have you tested it on any decent size project? IIRC this was super slow and that's why I explicitly disabled returning everything.

[groig]

@groig Have you tested it on any decent size project? IIRC this was super slow and that's why I explicitly disabled returning everything.

I tested it on elixir-ls itself and it's not bad.

[axelson]

I tested it on elixir-ls itself and it's not bad.

Elixir-ls is a rather small project compared to the applications that many developers are running on which can have thousands of modules.

[groig]

Sorry for the delay answering.

I understand that requesting every workspace symbol may be slow in some projects, but the feature does not impact the existing workspace symbol search. I see that lots of language servers decided to not implement this part of the spec (gopls, python-lsp-server, pyright, rust-analyzer). I personally find it useful as a replacement for ctags so my editor's client now requests the symbol list periodically to the server and keeps a local cache. Maybe the performance could be improved following a similar approach to #261 and returning only the symbols of the modules in the current application.

Feel free to close the pull request if the feature is not accepted.

[lukaszsamson]

@groig I revisited this idea in #1050 - with limiting indexing to only modules from the project it is feasible to query with empty needle