> unit, module, multi-module, and end-to-end. A great semantic insight. I still prefer to test complicated algorithms via the external interface. It does end

> unit, module, multi-module, and end-to-end. A great semantic insight. I still prefer to test complicated algorithms via the external interface. It does end up requiring some scaffolding code for generating inputs based on test cases, but code is for automating repetitive tasks, and they're pretty fast these days, so it's rarely a problem, even for many thousands of test variations. It enables you to test the interactions between your various unit-level variations, which is more likely to catch errors. Again, it also helps make your tests visible, along with the edge cases you're testing, and many times developers working at the unit test level are way more thorough than they actually need to be. Couple this with efficiencies around refactoring and it can actually save time.