Tag should have an interface it inherits and testcase config should have tagsFn

A super interface for Tag would allow people to make more interesting type hierarchies with their tags. Also, Test case config should have a tagsFn that passes the tags from defaultTestCaseConfig and allows each test case to override.

typealias TagsFn = (Set<Tag>) -> Set<Tag>

val a = Tag("a")
val b = Tag("b")

test("foo").config(tagsFn = { prev -> prev - a + b })

[jschneidereit]

SuperTag was just for illustrative purposes 🤣

[sksamuel]

As for the interface, changing Tag to an interface will break things (like the toString). So I think we might just be stuck. If you need inheritence, you could have a value inside your tag that is a sealed type.