Minertest

X = 0
Y = 0
Z = 0

function fuel()
    for i = 1,16 do
        itemInfo = turtle.getItemDetail(i)
        if itemInfo == nil then
        else
        if itemInfo["name"] == "minecraft:coal" then
            turtle.select(i)
            turtle.refuel(itemInfo["count"])
        end
        end
    end
end

function depositItems()
    fuel()
        for d = 1,16 do
            turtle.select(d)
            turtle.drop()
        end
end

function updateloc(x,y,z)
     X = X+x
     Y = Y+y
     Z = Z+z
end

function forward()
    turtle.dig()
    turtle.forward()
    updateloc(1,0,0)
end

function up()
    turtle.digUp()
    turtle.up()
    updateloc(0,1,0)
end

function down(amount)
    for p = 1,amount do
    turtle.digDown()
    turtle.down()
    updateloc(0,0,-1)
    end
end

function back(blockamount)
    turtle.turnRight()
    turtle.turnRight()
        for i = 1, blockamount do
            turtle.dig()
            forward()
            updateloc(-1,0,0)
        end
    turtle.turnRight()
    turtle.turnRight()
end


function dig()
fuel()
turtle.dig()
up()
turtle.dig()
up()
turtle.dig()
down(2)
fuel()
end

function digRight()
turtle.turnRight()
dig()
turtle.turnLeft()
end

function digLeft()
turtle.turnLeft()
dig()
turtle.turnRight()
end

function mineRows(amount)
    for p = 1,amount do
    digLeft()
    digRight()
    dig()
    forward()
    end
gohome = amount
goHome()
end

function goHome()
 back(gohome)
 gohome = 0
for i = 1,16 do
turtle.select(i)
turtle.drop()
end