"Linux command line utility ... In this contrived example you would need: Lots and lots of unit tests for the mathematical equations. Some integration

"Linux command line utility ... In this contrived example you would need: Lots and lots of unit tests for the mathematical equations. Some integration tests for the CSV reading and JSON writing No UI tests because there is no UI." As with all command line apps, the command line is the UI and requires testing ( input parameters, error messages, etc... )