In a medium bowl, combine undrained pineapple with dry cheesecake pudding mix.
Stir well until combined.
Stir in can of cherry pie filling.
Then gently stir in whipped topping.
If you like, you can always add in a few chopped walnuts or pecans. You can serve this right away. Just make sure you cover and store leftovers in the fridge. Want to make this more "figure-friendly"? Just substitute ingredients for their low/no sugar counterparts!