Basic Mining turtle 3x3 tunnel. Expecting length.

local args = { ... }

local loopCount = 1

if #args ~= 1 then
  print( "Requires length of tunnel" )
  error()
end

data = turtle.getItemDetail()

if not data then
  print( "Requires torches in current slot" )
  error()
end

if data then
  if data.name ~= "minecraft:torch" then
    print( "Requires torches in current slot" )
    error()
  end
end

print("Here we go!")

local deepTimes = tonumber(args[1])

local function checkIfDiamond()
  success, data = turtle.inspect()
  if success then
    if data.name == "minecraft:diamond_ore" then
      print( "Found diamond")
      error()
    end
  end
  success, data = turtle.inspectUp()
  if success then
    if data.name == "minecraft:diamond_ore" then
      print( "Found diamond")
      error()
    end
  end
  success, data = turtle.inspectDown()
  if success then
    if data.name == "minecraft:diamond_ore" then
      print( "Found diamond")
      error()
    end
  end
end

local function forwardLoop(loopAmount)
  for i=1,loopAmount do
    checkIfDiamond()
    turtle.dig()
    turtle.digUp()
    turtle.digDown()
    if (i % 10 == 0) and (loopCount == 2) then
      turtle.placeDown()
    end
    turtle.forward()
  end
  loopCount = loopCount + 1
end

local function turnLeft()
  turtle.turnLeft()
  turtle.dig()
  turtle.digUp()
  turtle.digDown()
  turtle.forward()
  turtle.turnLeft()
end

local function turnRight()
  turtle.turnRight()
  turtle.dig()
  turtle.digUp()
  turtle.digDown()
  turtle.forward()
  turtle.turnRight()
end

forwardLoop(deepTimes)
turnLeft()
forwardLoop(deepTimes)
turnRight()
forwardLoop(deepTimes)

print("Fin")