When Test Coverage Isn't Enough

Robert Roskam made a point on social media about the inadequacy of test coverage. 100% test coverage is not enough. Here’s an example as to why in Python: def division ( x , y ): return x / y If you pass in 0 for y , it’ll raise an error. You have to know to test for the value specifically. Test coverage won’t save you here. With 100% line coverage or branch coverages, it won’t be found. That’s…