Attempt to index nil with 'FindFirstChild' on minigame script

[flamez18 (GlorbleSeniorDeluxe)]

I got the error: ServerScriptService.Main:100: attempt to index nil with ‘FindFirstChild’ - Server - Main:100

does anyone know what went wrong?

script:

	gameRunning = false,
	playersAlive = {},
	currentMap = nil
}

local waitForChild = game.WaitForChild
local findFirstChild = game.FindFirstChild



local settingsModule = require(waitForChild(script, "Settings"))
local onWin = (function()
	local onWinModule = findFirstChild(script, "OnWin")
	
	if onWinModule then
		local onWinFunction = require(onWinModule)
		
		if type(onWinFunction) == "function" then
			return onWinFunction
		end
	end
end)()

local remoteEvent = waitForChild(game:GetService("ReplicatedStorage"), "Event")
local mapsStorage = waitForChild(game:GetService("ServerStorage"), "Maps"):GetChildren()

local playersService = game:GetService("Players")

function minigameModule.isPotentialGame()
	return playersService.NumPlayers >= settingsModule.minimumPlayers
end

function minigameModule:chooseMap()
    local chosenMap = mapsStorage[math.random(#mapsStorage)]:Clone() 
	if findFirstChild(chosenMap, "Spawns") then
		chosenMap.Parent = workspace
		chosenMap:MakeJoints()
		self.currentMap = chosenMap
		return chosenMap
	end
end

function minigameModule:spawnPlayers()
	local playersAlive = self.playersAlive
	local spawns = self.currentMap.Spawns:GetChildren()
	for index = 1, #playersAlive do
		local playerData = playersAlive[index]
		playerData.playerHumanoidRoot.CFrame = spawns[math.random(#spawns)].CFrame
	end
end

function minigameModule:runIntermission()
	if settingsModule.intermissionTime > 0 then
		for currentTime = math.floor(settingsModule.intermissionTime), 0, -1 do
			remoteEvent:FireAllClients("Timer", currentTime)
			wait(1)
		end
	end
	remoteEvent:FireAllClients("CeaseGUIs")
end

function minigameModule:getAlivePlayers()
	local playersAlive = {}
	for index, currentPlayer in next, playersService:GetPlayers() do
		local playerCharacter = currentPlayer.Character
		if playerCharacter then
			local playerHumanoidRoot = findFirstChild(playerCharacter, "HumanoidRootPart")
			local playerHumanoid = findFirstChild(playerCharacter, "Humanoid")
			if playerHumanoid and playerHumanoidRoot then
				table.insert(playersAlive, {
					player = currentPlayer,
					playerHumanoid = playerHumanoid,
					playerHumanoidRoot = playerHumanoidRoot
				})
			end
		end
	end
	return playersAlive
end

function minigameModule:isLegalGame()
	if #self:getAlivePlayers() >= settingsModule.minimumPlayers then
		return true
	end
end

function minigameModule:queryGameStart()
	if self.gameRunning then
		return
	elseif self.isPotentialGame() then
		self.gameRunning = true
		remoteEvent:FireAllClients("CeaseGUIs")
		self:runIntermission()
		
		if self:isLegalGame() then
			if settingsModule.roundDuration > 0 then
				
				local currentMap = self:chooseMap()
				local mapWeapons = currentMap:FindFirstChild("Weapons")
				
				local playersAlive = self:getAlivePlayers()
				self.playersAlive = playersAlive
				
				for index = 1, #playersAlive do
					local currentPlayer = playersAlive[index]
					local backpack = findFirstChild(currentPlayer.player, "Backpack")
					
					if backpack and mapWeapons then
						for index, weapon in next, mapWeapons:GetChildren() do
							weapon:Clone().Parent = backpack
						end
					end
					
					local connection
					connection = currentPlayer.playerHumanoid.Died:connect(function()
						connection:disconnect()
						table.remove(playersAlive, index)
						if #playersAlive < 2 then
							local winner = playersAlive[1]
							if winner then
								self:endGame(winner.player.Name .. " has won!", winner.player)
							else
								self:endGame("No one has won!")
							end
						end
					end)
				end
				
				if mapWeapons then
					mapWeapons:Destroy()
				end
				
				self:spawnPlayers()		
				
				remoteEvent:FireAllClients("Message", currentMap.Name .. " was chosen!", 5)
				
				for currentTime = settingsModule.roundDuration, 0, -1 do
					if not self.gameRunning then
						return
					end
					remoteEvent:FireAllClients("Timer", currentTime)
					wait(1)
				end
				self:endGame("The timer ran out! No one has won!")
			end
			
		else
			self:endGame("Not enough players alive to begin the round!")
		end
	else
		local remainingPlayers = settingsModule.minimumPlayers - playersService.NumPlayers
		remoteEvent:FireAllClients("Message", "Waiting for " .. remainingPlayers .. " player" .. (remainingPlayers > 1 and "s" or "") .. " to join.")
	end
end

function minigameModule:endGame(outputMessage, winner)
	if self.gameRunning then
		
		self.gameRunning = false
		self.currentMap:Destroy()
		self.currentMap = nil
		
		if winner and onWin then
			onWin(winner)
		end
		
		for index, player in next, playersService:GetPlayers() do
			player:LoadCharacter()
		end
		
		wait(1)
		
		remoteEvent:FireAllClients("Message", outputMessage, 5)
		
		wait(5)
		
		self:queryGameStart()
	end
end

function minigameModule:removePlayer(player)
	if self.gameRunning then
		for index = 1, #self.playersAlive do
			if self.playersAlive[index].player == player then
				table.remove(self.playersAlive, index)
				if #self.playersAlive <= 1 then
					self:endGame("Not enough players to continue the game.")
				end
				break
			end
		end	
	end
end

playersService.PlayerAdded:connect(function()
	minigameModule:queryGameStart()
end)

playersService.PlayerRemoving:connect(function(player)
	minigameModule:removePlayer(player)
end)

[SageToxigen (Raixon)]

When it says nil, it means that the object doesn’t exist, and you’re attempting to index it with :FindFirstChild() or anything else.

So it has to do with the variable that’s nil.

[weakroblox35]

@flamez18

local waitForChild = game.WaitForChild
local findFirstChild = game.FindFirstChild

what is this?? what are you trying to do?

[flamez18 (GlorbleSeniorDeluxe)]

I was trying to make it easier to reference them, is that what’s causing the problem?

[weakroblox35]

yes ?? youre literlaly looking for instances inside game datamodel

[flamez18 (GlorbleSeniorDeluxe)]

So how would I go about fixing this, I removed the two things at the top and replaced all the instances that needed it.

[weakroblox35]

does it still error with indexing nil

[flamez18 (GlorbleSeniorDeluxe)]

yes, I don’t know what could be going wrong.

[SageToxigen (Raixon)]

Aha, found the problem.

This code, in math.random, it has minimum value, but doesn’t have maximum value.

local chosenMap = mapsStorage[math.random(#mapsStorage)]:Clone() 

I supposed you intended it to be like this:

local chosenMap = mapsStorage[math.random(1, #mapsStorage)]:Clone() 

[flamez18 (GlorbleSeniorDeluxe)]

The change did, oddly enough, make the gui timer work again, but the error is still present.

[SageToxigen (Raixon)]

I’ve modified this a bit, does it work for you?

function minigameModule:chooseMap()
	local chosenMap = mapsStorage[math.random(1, #mapsStorage)]:Clone() 
	if chosenMap:FindFirstChild("Spawn") then
		chosenMap.Parent = workspace
		chosenMap:MakeJoints()
		self.currentMap = chosenMap
		return chosenMap
	end
end

[flamez18 (GlorbleSeniorDeluxe)]

So the findFirstChild error is gone, but now I have the error: MakeJoints is not a valid member of Folder “Workspace.Sword Fight!”

[SageToxigen (Raixon)]

Well I just found out that MakeJoints() is now deprecated, same for BreakJoints()

So feel free to remove chosenMap:MakeJoints(), but if your map needs some welding, you can install a plugin called NAAP Tools, which has many options including welding parts that are close together automatically.

[flamez18 (GlorbleSeniorDeluxe)]

So rid of the make joints error, but the original error is somehow back for the same line.

ServerScriptService.Main:97: attempt to index nil with ‘findFirstChild’

[SageToxigen (Raixon)]

I’ve modified it.

function minigameModule:getAlivePlayers()
	local playersAlive = {}
	for _, currentPlayer in pairs(playersService:GetPlayers()) do
		local playerCharacter = currentPlayer.Character
		if playerCharacter then
			local playerHumanoidRoot = playerCharacter:FindFirstChild("HumanoidRootPart")
			local playerHumanoid = playerCharacter:FindFirstChild("Humanoid")
			if playerHumanoid and playerHumanoidRoot then
				table.insert(playersAlive, {
					player = currentPlayer,
					playerHumanoid = playerHumanoid,
					playerHumanoidRoot = playerHumanoidRoot
				})
			end
		end
	end
	return playersAlive
end

I’ve seen many developers add a variable to the index in for loops despite not using it, so please, add an underscore to it if you’re not using it.

The underscore (_) variable name is a convention in lua that indicates an unused variable.

This prevents memory leaks.

[flamez18 (GlorbleSeniorDeluxe)]

I’m sorry to say this, but the error is still persisting, ServerScriptService.Main:97: attempt to index nil with ‘findFirstChild’

[SageToxigen (Raixon)]

I’ve modified the entire code you showed.

local minigameModule = nil

local settingsModule = require(script:FindFirstChild("Settings"))
local onWin = (function()
	local onWinModule = script:FindFirstChild("OnWin")

	if onWinModule then
		local onWinFunction = require(onWinModule)

		if type(onWinFunction) == "function" then
			return onWinFunction
		end
	end
end)()

local remoteEvent = game:GetService("ReplicatedStorage").Event
local mapsStorage = game:GetService("ServerStorage").Maps:GetChildren()

local playersService = game:GetService("Players")

function minigameModule.isPotentialGame()
	return playersService.NumPlayers >= settingsModule.minimumPlayers
end

function minigameModule:chooseMap()
	local chosenMap = mapsStorage[math.random(1, #mapsStorage)]:Clone() 
	if chosenMap:FindFirstChild("Spawn") then
		chosenMap.Parent = workspace
		chosenMap:MakeJoints()
		return chosenMap
	end
end

function minigameModule:spawnPlayers()
	local playersAlive = self.playersAlive
	local spawns = self.currentMap.Spawns:GetChildren()
	for index = 1, #playersAlive do
		local playerData = playersAlive[index]
		playerData.playerHumanoidRoot.CFrame = spawns[math.random(#spawns)].CFrame
	end
end

function minigameModule:runIntermission()
	if settingsModule.intermissionTime > 0 then
		for currentTime = math.floor(settingsModule.intermissionTime), 0, -1 do
			remoteEvent:FireAllClients("Timer", currentTime)
			wait(1)
		end
	end
	remoteEvent:FireAllClients("CeaseGUIs")
end

function minigameModule:getAlivePlayers()
	local playersAlive = {}
	for _, currentPlayer in pairs(playersService:GetPlayers()) do
		local playerCharacter = currentPlayer.Character
		if playerCharacter then
			local playerHumanoidRoot = playerCharacter:FindFirstChild("HumanoidRootPart")
			local playerHumanoid = playerCharacter:FindFirstChild("Humanoid")
			if playerHumanoid and playerHumanoidRoot then
				table.insert(playersAlive, {
					player = currentPlayer,
					playerHumanoid = playerHumanoid,
					playerHumanoidRoot = playerHumanoidRoot
				})
			end
		end
	end
	return playersAlive
end

function minigameModule:isLegalGame()
	if #self:getAlivePlayers() >= settingsModule.minimumPlayers then
		return true
	end
end

function minigameModule:queryGameStart()
	if self.gameRunning then
		return
	elseif self.isPotentialGame() then
		self.gameRunning = true
		remoteEvent:FireAllClients("CeaseGUIs")
		self:runIntermission()

		if self:isLegalGame() then
			if settingsModule.roundDuration > 0 then

				local currentMap = self:chooseMap()
				local mapWeapons = currentMap:FindFirstChild("Weapons")

				local playersAlive = self:getAlivePlayers()
				self.playersAlive = playersAlive

				for index = 1, #playersAlive do
					local currentPlayer = playersAlive[index]
					local backpack = currentPlayer.player.Backpack

					if backpack and mapWeapons then
						for index, weapon in next, mapWeapons:GetChildren() do
							weapon:Clone().Parent = backpack
						end
					end

					local connection
					connection = currentPlayer.playerHumanoid.Died:connect(function()
						connection:disconnect()
						table.remove(playersAlive, index)
						if #playersAlive < 2 then
							local winner = playersAlive[1]
							if winner then
								self:endGame(winner.player.Name .. " has won!", winner.player)
							else
								self:endGame("No one has won!")
							end
						end
					end)
				end

				if mapWeapons then
					mapWeapons:Destroy()
				end

				self:spawnPlayers()		

				remoteEvent:FireAllClients("Message", currentMap.Name .. " was chosen!", 5)

				for currentTime = settingsModule.roundDuration, 0, -1 do
					if not self.gameRunning then
						return
					end
					remoteEvent:FireAllClients("Timer", currentTime)
					wait(1)
				end
				self:endGame("The timer ran out! No one has won!")
			end

		else
			self:endGame("Not enough players alive to begin the round!")
		end
	else
		local remainingPlayers = settingsModule.minimumPlayers - playersService.NumPlayers
		remoteEvent:FireAllClients("Message", "Waiting for " .. remainingPlayers .. " player" .. (remainingPlayers > 1 and "s" or "") .. " to join.")
	end
end

function minigameModule:endGame(outputMessage, winner)
	if self.gameRunning then

		self.gameRunning = false
		self.currentMap:Destroy()
		self.currentMap = nil

		if winner and onWin then
			onWin(winner)
		end

		for index, player in next, playersService:GetPlayers() do
			player:LoadCharacter()
		end

		wait(1)

		remoteEvent:FireAllClients("Message", outputMessage, 5)

		wait(5)

		self:queryGameStart()
	end
end

function minigameModule:removePlayer(player)
	if self.gameRunning then
		for index = 1, #self.playersAlive do
			if self.playersAlive[index].player == player then
				table.remove(self.playersAlive, index)
				if #self.playersAlive <= 1 then
					self:endGame("Not enough players to continue the game.")
				end
				break
			end
		end	
	end
end

playersService.PlayerAdded:connect(function()
	minigameModule:queryGameStart()
end)

playersService.PlayerRemoving:connect(function(player)
	minigameModule:removePlayer(player)
end)

Please use :FindFirstChild() and :WaitForChild() accordingly.

[flamez18 (GlorbleSeniorDeluxe)]

Ok, so as soon as I opened the game I got the error: ServerScriptService.Main:21: attempt to index nil with ‘isPotentialGame’

[SageToxigen (Raixon)]

Oops, remove the local minigameModule = nil that I added to remove orange lines

[flamez18 (GlorbleSeniorDeluxe)]

The one at the top, because when I remove that it makes all of the references of it become unknown