Why Most Unit Testing is Waste
Object orientation turned the design world upside-down. First, the design units changed from things-that-computed to small heterogeneous composites called objects that combine several programming artefacts, including functions and data, together inside one wrapper. (…) That made it impossible to reason about run-time behaviour of code by inspection alone. You had to run the program to get the faintest idea of what was going on. So, testing became in again. Original PDF version of article
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