Disallow ? on values

How are you using the lua-language-server?

Visual Studio Code Extension (sumneko.lua)

Which OS are you using?

Windows

What is the issue affecting?

Type Checking

Expected Behaviour

? is not a type, and should only be used when marking fields as optional. If nil is explicitly allowed as a value, | nil should be used. This is in line with TypeScript.

Actual Behaviour

? does not add | nil to the value type, and the second option should be disallowed.

Reproduction steps

---@class Foo
---@field foo? string
---@field bar string?
---@field baz string | nil
local test = {};

function Foo()
    return test.foo, test.bar, test.baz
end;

Additional Notes

No response

Log File

No response

Empieza reproduciendo el comportamiento de la comprobación de tipos en la Visual Studio Code Extension (sumneko.lua) usando el fragmento de Lua del issue. Se considera terminado cuando string? no está permitido, foo? string sigue siendo la forma de campo opcional y string | nil permite explícitamente nil.