Bake cake according to directions is a 9x13 pan. In a saucepan over medium heat, combine pineapple with juice, sugar, pudding, and coconut. Simmer 5 minutes. Using a wooden spoon handle, poke holes in warm cake. Slowly pour pineapple mixture over cale and spread evenly. Cool. Spread whipped topping evenly over cake and sprinkle with nuts. Chill at least 2 hours before serving.