Semantic Token Highlighting

[0x57e11a]

many language servers have support for semantic tokens, giving each token some information on what it actually refers to, which can be styled

this would be a very helpful feature for teal development, as the most common lua extension does include semantic tokens

example

given:

local function do_work(worker, arg)
	worker(arg) -- worker and arg are `parameter`
end

local test = { -- test is `variable.declaration`
	x = 1,
	y = 2,
	thing = function(x, y)
		return x + y
	end,
}

local worker = function(arg) -- worker is `function.declaration`
	return arg.thing(arg.x, arg.y) -- arg is `parameter`, .thing is `method`, and .x and .y are `property`
end

do_work(worker, test) -- do_work and worker are `function`, test is `variable`

local other = do_work -- it knows that do_work is `function`, and thus other is `function.declaration`

saved as lua (viewed with sumneko.lua):

saved as tl (viewed with pdesaulniers.vscode-teal):

...however, this is nontrivial, especially given the ways the vscode-teal currently operates, wrapping tl, it'd require either direct integration with the base language tl.tl (via some sort of --dump-semantics flag), or a re-implementation of type inference in the language server (a la rust-analyzer reimplementing rustc behaviors for LSP purposes)

either way this is not a small task, so it's entirely understandable if people don't wish to put the time into it ^v^

[pdesaulniers]

Maybe it would be possible to implement a bit of semantic highlighting by using the output of tl types and tree-sitter.

With that said, now that teal-language-server exists, I don't really plan to work on vscode-teal's built-in language server any further... I think this feature should be implemented in teal-language-server instead!