New Luau Type Solver Incorrectly Expecting 'Model' Type

Bug Reports Studio Bugs
,
1

The UseNewLuauTypeSolver feature appears to be incorrectly expecting the Model type globally or failing to resolve the correct type after a variable has been set.
This leads to “cascading” type errors where numbers, booleans, and even Vector3 properties are treated as if they belong to a Model instance.
The bug also persists when passing arguments through RemoteEvents. Even when passing strings, booleans, or custom IDs, the solver flags every single argument, demanding a Model instead.
This bug appears to be specific to Team Create sessions. When testing the exact same code in a local file copy (.rbxl) of the game, the warnings do not appear. This suggests the new solver is incorrectly interpreting the environment or the DataModel hierarchy specifically during live collaborative sessions.

Visual Aids:
Published game:


image
image837×244 15.8 KB

Local file copy:
image
image1209×883 62.7 KB

Direct Links:
Affected Game: https://www.roblox.com/games/130580316728867/Underbound-Test-Place-Reborn
Developer Group: Aurora's Workshop - Roblox

System Information:
CPU: AMD Ryzen 9 3900X
GPU: RTX 2070 SUPER
RAM: 32GB
OS: Windows 11
STUDIO VERSION: 0.715.1.7151119 (64bit)

Beta Features:
3D Importer in ACE, AvatarAbilities Character Controller Library, Dragger QoL Improvements, Editable Mesh/Image to static content conversion API, Face Capture, glTF Export, Improved Constraint Tool, Improved Solid Modeling Controls, In-Experience Avatar Auto Setup, Live Animation Creator, New Studio Camera Controls, New Video API, Party Simulator, Reimport, Revamped Asset Manager, Script Sync, Script are Non-Script by Default, Solid Modeling On Meshes, Texture Generator, Video Uploads.

1 Like
2

Hello! That is quite bizarre, and it’s definitely a bug for Luau to act differently on Team Create versus locally.

When testing the exact same code in a local file copy (.rbxl) of the game, the warnings do not appear.

Would you be able to share this RBXL privately or otherwise produce a minimal reproduction?

3

The problem is that this bug only happens in this specific game’s studio. I tried using the same code in a new game with Team Create enabled, but the orange linters didn’t show up there.

I can’t share my full game file for privacy reasons. Also, because the bug doesn’t happen in a new file, sending a reproduction file wouldn’t show you the problem anyway. It seems like the bug is stuck only in this specific project’s environment.

The bare minimum I can send is the code snippets where the issue is happening:

function SecondsToReadable(seconds: number)
    local year = 31536000
    -- Type Error: Expected 'Model', got 'number'
    seconds = seconds % year 
    return "example"
end

-- Type Error: Expected 'Model', got 'boolean'
workspace:SetAttribute("Test", true)

-- Every argument below says: Expected 'Model'
ABILITIES_EVENT:FireAllClients(
    "CharacterName", 
    "Ability", 
    "OnHit", 
    "ExampleID"
)

for Index, Part: BasePart in Model:GetChildren() do
    -- Type Error: Key 'X' not found in external type 'Model'
    print(Part.Position.X) 
end