Paper author here.  As someone already mentioned, the suites were made by picking a random subset of the test cases written by the developers, not by using a suite generation tool.<p>Now, our method is arguably not 100% realistic either, because in practice different parts of the program will have different coverage.  Some kind of weighted random sampling might make suites that are a bit closer to &quot;real&quot; suites.  I&#x27;ve been thinking about looking into that.  I think our suites are realistic enough to make the results worthwhile, though.