Chunky Cranberry Fluff Recipe

1 pound cranberries

chopped

1 cup white sugar

1 (16 ounce) package frozen whipped topping (such as Cool Whip®)

thawed

1 (10.5 ounce) package miniature marshmallows

1 cup chopped walnuts

1 (15 ounce) can crushed pineapple