One of the most fundamental questions you can ask about testing is “Did I test that?” But there isn’t a binary answer to that question. We know when we haven’t tested at all, but there is no such thing as infinite testing. We test in different ways, at different times, in different situations, for different reasons. And so, responsible testers must be able to reason about and assess the relative depth of their testing.
This talk is how to think about testing depth. We’re not simply thinking about structural depth unit testing, sub-system testing, system testing, or end-to-end testing. Instead, we’re talking about the thoroughness of testing — and the capacity of testing to find elusive bugs that matter.