I often hear this: Why should we extract this code? We only use it in one place. It doesn’t make sense to extract it. And yet, that same person wants to write tests for private (or otherwise invisible) behavior. That person is only hurting themselves: they want to treat this code like a separate thing (because they want to test it), but they resist extracting it because “it doesn’t feel right”. I have safely extracted numerous mini-frameworks and mini-libraries and my only regret rema...
