Question

How can I compare the items in two lists and create a new list with the difference in Groovy?

Answer 1

Collections intersect might help you with that even if it is a little tricky to reverse it. Maybe something like this:

def collection1 = ["test", "a"]
def collection2 = ["test", "b"]
def commons = collection1.intersect(collection2)
def difference = collection1.plus(collection2)
difference.removeAll(commons)
assert ["a", "b"] == difference