CODE EXAMPLE FOR LUA

roblox make rainbow part

local TweenService = game:GetService("TweenService")
local part = workspace.ColorPart
local red = Color3.fromHSV(0, 1, 1)
local hue = 0
part.Color = red
local partColorTweenInfo = TweenInfo.new(1 --[[seconds]])
while true do
	hue += (360 / 12) / 360
	if hue > 1 then
		hue -= 1
	end
	local tweenPartColor = TweenService:Create(part, partColorTweenInfo, {Color = Color3.fromHSV(hue, 1, 1)})
	tweenPartColor:Play()
	tweenPartColor.Completed:Wait()
end