Requiring/Using a module from within a local script crashes studio in edge-case scenario

[lineridermasterman]

We have found an edge-case scenario where using a module within a local script causes studio to immediately crash. This includes both as soon as typing in the code, to attempting to reopen the script. If you reopen studio and the script is open by default, studio also instantly crashes. Below is how you can replicate this bug for yourself:

Bug in action:

1. Create LocalScript called CrashTest1 in StarterPlayerScripts

2. Create ModuleScript called CrashTest2 that is a child of CrashTest1 (CrashTest2.Parent = CrashTest1) with content:

local tbl = {}

function tbl:f1(state)
    self.someNonExistentvalue2 = state
end

function tbl:f2()
    self.someNonExistentvalue:Dc()
end

function tbl:f3()
    self:f2()
    self:f1(false)
end
return tbl

3. Save CrashTest2

4. Paste the following into CrashTest1:

local tbl = require(script.CrashTest2)
tbl:f3()

Roblox Studio should now instantly crash

Expected behavior

Even if the script would error in play-mode, studio should not be crashing.

A private message is associated with this bug report

[MrZahariks]

Its the same with server scripts, not just the client

[dfgworm]

I have also encountered this exact problem this morning (like 3 hours ago from now)
It happens with any kind of script, local, server or module, but only when you open the script in script editor (if the script opens when you enter the place, then you get instant crashes whenever you open the place).
This happens to me and 2 other people.
Most of scripts on our large place just crash studio with no warning and no dump files generated.
This was not happening just yesterday.

Code posted here seems to be the minimum code required to reproduce this.
What i could figure out is that disabling
Studio Settings → Script Editor → Signature Highlight
stops it from crashing when opening scripts, but it still crashes when you try to type anything.
Disabling another setting
Studio Settings → Script Editor → On-Type Autocomplete
solves the problem altogether, but we lose all the autocomplete tips, which makes writing code pretty difficult.

From what i can tell autocomplete tips were updated just today (new icons or something?)

[WheretIB]

Thank you for the reports, we will be rolling back a change that’s involved in this today.

And we will also have a fix for the crash in the future Roblox Studio update.

[ScriptArchiver]

When can we expect the roll back?
Since this issue prevents me from editing most of my Scripts.
(even with disabled autocompletion)

Thanks in advance

[tommysalami68]

Also experiencing this, it’s pretty urgent as none of our engineering team can access the game at all. Studio crashes on opening the place file (including a saved copy) even after a re-install.

[bytesleuth]

I’m not using a module within a local script but when I open up a localscript it crashes studio I’ve reported this but still haven’t got an answer in like 3h, it’s frustrating because I can’t work on my game.

[bytesleuth]

Turning all this off has just fixed it for me but now it’s gonna be a pain to code.

[amets_iratxo (iratxo)]

The change has been rolled back now. You should be able to continue editing with autocomplete and signature help enabled again, but please let us know if there’s additional issues.