[Feature] Add action to autorequire undefined globals

[sewbacca]

I attempted to implement #1938.
This is how it looks in action:

How to make this less of a hack?

lua-language-server/script/core/code-action.lua

Lines 730 to 739 in 62d4d35

	-- TODO: Is there a better way to detect undefined-global?
	for _, diag in ipairs(diagnostics) do
	if diag.code == 'undefined-global' then
	for _, potglobal in ipairs(potentialGlobals) do
	if diag.message:find(potglobal.name) then
	addPotentialRequires(potglobal)
	end
	end
	end
	end

How to add tests? I suppose they should go somewhere here:

lua-language-server/test/code_action/init.lua

Line 158 in 62d4d35

-- TODO: Add some tests for ACTION_AUTOREQUIRE

But how do I create the stubs for other modules?

[sumneko]

But how do I create the stubs for other modules?

See test/crossfile

[sewbacca]

I added a testcase, and used the test/crossfile directory as a reference (though the actual test lies inside the code_action/init.lua file). I implemented a custom TEST_CROSSFILE function to setup the unit test. I have also modified the eq function, mainly to return a more friendly error message, showing exactly the keypath that does not match.

I also don't use diagnostic messages anymore to determine if a global is undefined, so that I can add the refactor.rewrite command. Instead I use the core.diagnostic.undefined-global function to report the undefined globals back to me and double check, if the requested position from the user is actually undefined. It still feels a bit of a hack, but it should be much more robust now, since I don't use a diagnostic message as a reference. Is this function called when the user asks for code fixes or more often? Because as far as I understand, the function checks the whole ast, not just only the part in which we are interested. Is there maybe a function, which can check if a given variable is an undefined global directly?

The undefined-global function is marked as async, but the code-action function is not. Can I safely add a ---@async statement to remove the warning, since the tests pass?

[sumneko]

I have also modified the eq function, mainly to return a more friendly error message, showing exactly the keypath that does not match.

Greate, thank you!

Is this function called when the user asks for code fixes or more often? Because as far as I understand, the function checks the whole ast, not just only the part in which we are interested. Is there maybe a function, which can check if a given variable is an undefined global directly?

There is currently no such function. You can do the following:

1. Extract the check function in undefined-global into a separate function.
2. Use guide.eachSourceBetween to only check the interested part.
3. Cache the results in node.

---@class vm.node
---@field package _undefined_global? boolean

function api.isUndefinedGlobal(src)
    local node = vm.compileNode(src)
    if node._undefined_global == nil then
        node._undefined_global = checkIsUndefinedGlobal(src)
    end
    return node._undefined_global
end

The undefined-global function is marked as async, but the code-action function is not. Can I safely add a ---@async statement to remove the warning, since the tests pass?

Yes, all code is executed within a coroutine during testing.

(Translated by ChatGPT)

[sewbacca]

I've moved the undefined global check into script/vm and rewrote code-action and diagnostics/undefined-global to use the vm instead. I also added another test, if an init file is present. I believe it is now ready for review.

[sewbacca]

Fixed formatting (I dont know how that happened)
Renamed _undefined_global to undefinedGlobal

[sumneko]

Nice work, thank you!