yeah - it's very nully as it stands. Those are great ideas, thanks, I'll have a play tomorrow.

I would also suggest an overload to it with a double chance

fun <A> Arb<A>.orNull(nullChance: Double = 0.25): Arb<A?>

That's fine, it can pass a function to the other of

{ it.random.nextDouble() < nullChange }

I've actually done both, I'm close to being done - just putting some docs/kdoc, will submit a PR tonight, happily remove either version though. In our codebase we use orNull() a lot with the old kotlintest to replicate the input from another system being null, and I can see us using (

orNull(0.25)

a lot, but that's not to say that version of the function needs to exist in Kotest, it'd happily live in our code)

Sounds good

Just pushed to the branch/ PR: https://github.com/kotest/kotest/pull/1414