There's no debate about testing stateless functions. I think the debate is in whether the ledger reflects a cost benefit of spending all the time mocking up dif

There's no debate about testing stateless functions. I think the debate is in whether the ledger reflects a cost benefit of spending all the time mocking up different functionalities in order to test stateful components or components with external dependencies. Since these are hard to calculate ahead of time, it really does become a question of engineering culture and time to market.