LuaLS / LuaLS/lua-language-server

Returning a value as a class doesnt set the fields

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Dominant language
Lua
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Description

### 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?

Annotations, Type Checking

### Expected Behaviour

`value` be member of `MyClass`

### Actual Behaviour

![grafik](https://github.com/LuaLS/lua-language-server/assets/15840247/d0ede492-0113-4d95-beb5-391a77508f8f)
`value` is not a member

### Reproduction steps

```lua
local function myConstructor()
---@class MyClass
return { value = true }
end

local o = myConstructor()
print(o.value)
```

### Additional Notes

This should also work with a `setmetatable` variant:

```lua
---@class MyClass
local MyClass = {}
MyClass.__index = MyClass

local function myConstructor()
---@class MyClass
return setmetatable({ value = true }, MyClass)
end

local o = myConstructor()
print(o.value)
```

It does work with this workarround:

```lua
local function myConstructor()
---@class MyClass
local o = setmetatable({ value = true }, MyClass)
return o
end
```

### Log File

_No response_

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the two constructor examples from the issue and trace how the language server interprets the @class annotation on a returned table. Compare this with the working local-variable workaround and add a regression test covering both direct returns and setmetatable returns. Done means value is recognized as a member of MyClass during type checking.

Written by the indexing model from the issue text.

Assessment

Tech stack
lua
Domain
devtools
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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