Blocks with literal null as id in VARIABLE or LIST field behave incorrectly

[Minater247]

Expected Behavior

The minimal example I created should increment the value of currListNotes[1] every iteration. However, it seems to add random values - in turn, breaking the output. This only occurs when the compiler is enabled, when disabled or running on regular Scratch, the issue does not occur.

For example, here is a screenshot of a regular number, as it should be:

Actual Behavior

Here is a screenshot of what happens when the error occurs:

This has something to do with the double-manipulations, as when I change the value of the above block to not be divided by 19.5 or the like, it does not encounter the same issue, but instead gives random whole numbers.

Steps to reproduce

Open the attached file, and click on the script. When run, the displayed list will show erratic numbers if and only if the compiler is enabled.

Minimal Example.zip

Operating system and Browser

Windows 11 22H2 build 22621.4317, Firefox 134.0.1 (64-bit)

[GarboMuffin]

github will let you upload the sb3 if you put it inside a zip

[Minater247]

Got it, thank you! Uploaded now, tried to remove as much of the surrounding code where it still occurred to narrow it down.

[GarboMuffin]

simpler reproduction

Minimal Example.zip

[GarboMuffin]

What's happening is these list IDs are null, which we then handle incorrectly (internal variable object cache collision because using the same key null).

There are some other weird things like the replace blocks not having shadows when you drag out the value

Are you using some project compressor or just whatever turbowarp does?

[Minater247]

I did write a script about a year back to take out unused shadows, but it doesn't touch list IDs. I definitely didn't set them to null though - I've never seen that. I'll go read over the code again and make sure that's not something weird I did and forgot about.

[Minater247]

Looking over everything I don't see anything that would even be capable of outputting 'null' raw into the file without quotes, so it's not the script. So all I can account for is the shadows, I don't know why there's the nulls.

That is also spot on - after going in to the JSON and manually putting back the list IDs, it's back to normal! It also seems to stay that way after saving, both in the browser and on the desktop, so I doubt it was related here. Just triggered a weird edge case, I guess. I don't know if you need this commit for reference or commit messages since you said it was an actual issue with null handling, so I'll leave it open for a bit, but that should be everything. Thank you!

[GarboMuffin]

Original project will work fine in next update.

Not sure how many other weird bugs the null variable IDs might cause (I imagine lots; the way vanilla Scratch handles this is very quirky) so recommend trying to figure out how that happened.

I'm still pretty suspicious of that script but oh well