How to drastically improve code coverage?
- by Peter Kofler
I'm tasked with getting a legacy application under unit test. First some background about the application: It's a 600k LOC Java RCP code base with these major problems
massive code duplication
no encapsulation, most private data is accessible from outside, some of the business data also made singletons so it's not just changeable from outside but also from everywhere.
no business model, business data is stored in Object[] and double[][], so no OO.
There is a good regression test suite and an efficient QA team is testing and finding bugs. I know the techniques how to get it under test from classic books, e.g. Michael Feathers, but that's too slow. As there is a working regression test system I'm not afraid to aggressively refactor the system to allow unit tests to be written.
How should I start to attack the problem to get some coverage quickly, so I'm able to show progress to management (and in fact to start earning from safety net of JUnit tests)? I do not want to employ tools to generate regression test suites, e.g. AgitarOne, because these tests do not test if something is correct.
