Annotate Type of Return Statement

[firas-assaad]

I have module Lua files with data in a structured format, and I'd like to explicitly annotate the returned value. I tried the following:

-- module A

---@alias My_Format { x : integer, y: integer }

---@type My_Format
return {
    x = 1,
    y = 'hello', -- no warnings
}

This doesn't result in any checking of the return type. Instead, I can annotate a local variable and return it:

---@type My_Format
local result = {
    x = 1,
    y = 'hello' -- warning: assign-type-mismatch
}

return result

Using a local variable isn't a big deal, but it forces me to structure code differently just to accommodate the language server. It would be nice if it understood the annotation before the return statement.

[filipekiss]

Did you ever figure this out? I have hit this same wall and I can't find a working solution other than create and export local variables, which is not ideal

[firas-assaad]

It's not supported as far as I know. I created a feature request issue for it #2144

The maintainer has been busy recently, so I doubt it'll be picked up any time soon. For now I'm simply introducing local variables everywhere.

[filipekiss]

Thanks for the update. I'll subscribe to the request and wait (and sprinkle locals everywhere).