Weird `:GetDescendants()` behaviour with for loop

Help and Feedback Scripting Support
, ,
#1

Hello forum,
I’ve ran into this issue (could be a bug or just I am doing it wrong so I am using the scripting support tag) :

print(#self.Model:GetDescendants())
for i, instance in self.Model:GetDescendants() do
	print(i)
end

The output to this code is → 

  13:28:07.610  87  -  Server - Tycoon:71
  ...
  13:28:07.627  76  -  Server - Tycoon:73
  13:28:07.627  77  -  Server - Tycoon:73
  13:28:07.627  78  -  Server - Tycoon:73
  13:28:07.627  79  -  Server - Tycoon:73
  13:28:07.628  80  -  Server - Tycoon:73
  13:28:07.628  81  -  Server - Tycoon:73
  13:28:07.628  82  -  Server - Tycoon:73

Why is it that with loop it only gets to 82? I need it to loop thru the whole :GetDescendants(). If you need any more information, please ask below

#2

Are you running this code on the client? There’s a possibility that the code is running before everything in that model has loaded on the client.

#3

I am running this on The server. Even after adding like wait(5), the output is the same.

#4

Could you show a picture of the descendants?

#5

Zrzut ekranu 2022-07-16 o 15.21.33
Zrzut ekranu 2022-07-16 o 15.21.33956×670 94.8 KB

Zrzut ekranu 2022-07-16 o 15.21.40
Zrzut ekranu 2022-07-16 o 15.21.40946×39 12.9 KB

They are mostly models which contain meshparts or just parts.
This is how I discovered the bug, I was adding new models but the code couldn’t find them

#6

You’re using self, where did you put the code in? Without seeing the other part of your code it looks normal.

#7

The code runs from ServerScriptService as a server script. It creates the new self object for every player in .PlayerAdded event. Than it calls this function → 

function Tycoon:LockAll()
	print(#self.Model:GetDescendants())
	for i, instance in self.Model:GetDescendants() do
		print(i)
		if CollectionService:HasTag(instance, "Unlockable") then
			self:Lock(instance)
		else
			self:AddComponents(instance)
		end
	end
end

Which not long ago started this weird behaviour where it wouldn’t "Lock" the parts even if they had the "Unlockable" tag, that’s why i tried to see where the problem is and it seems that it doesn’t loop thru all the parts which I gave screenshot in previous reply.
If I print instance, there is no Test Model which is in the screenshot in the previous post.

#8

Is anything modified that could cause any issues while the code’s running? Note that you can also use print(instance.Name) or something similar to find out which instances aren’t reporting properly.

#9

I don’t think anything is modifided while code’s running. All those models are there in studio. It doesn’t see Test or any part added with the tag. Although when I add a part, the
print(#self.Model:GetDescendants()) changes.

#10

Try editing those parts with the tag to see if it changes anything, I don’t know what exactly to do from there, but it’d be helpful to see what happens.

#11 
function Tycoon:LockAll()
	for i, instance in self.Model:GetDescendants() do
		if instance.Name == "Canon1" or instance.Name == "Test" then
			print(instance.Name, 0)
		end
end

Output → 

15:47:27.702  Canon1 0  -  Server - Tycoon:74

Where both Test and Canon1 are in the descendats. Having print self.Model:GetDescendants(), you can find both.

#12

As a test, can you get descendants and store it in a variable, then print # for the amount and then loop through it?

#13

Already tried it, didn’t work. What works is this :

function Tycoon:LockAll()
	for x, y in ipairs(self.Model:GetDescendants()) do
		if y.Name == "Test" then
			print(1)
		end
	end
	for i, instance in ipairs(self.Model:GetDescendants()) do
		if instance.Name == "Test" then
			print(2)
		end
		if CollectionService:HasTag(instance, "Unlockable") then
			self:Lock(instance)
		else
			self:AddComponents(instance)
		end
	end
end

This prints 1 but still not 2 even its excatly the same thing…
I will just try to rewrite the whole loop and see…