I mean before you've written any code at all. Like, you have to have the tests for all units created before you start writing the code for any unit. That's what

I mean before you've written any code at all. Like, you have to have the tests for all units created before you start writing the code for any unit. That's what the person I responded to made it sound like. Writing tests before you work on the unit you're working on shouldn't be a problem because you should know what that unit is supposed to do. If you don't, then it doesn't matter if you do TDD, Agile, BDD, or whatever. You're not going to be able to do it right. Go have a conversation with someone to find out what that is supposed to do.