On Tue, 19 Jun 2012, Jacques Carette wrote:
Its main novel features are:
* introduces a number of /testing strategies/ and /strategy combinators/ * introduces a variety of test execution methods * guarantees uniform sampling (at each rank) for the random strategy * guarantees both uniqueness and coverage of all structures for the exhaustive strategy * introduces an /extreme/ strategy for testing unbalanced structures * also introduces a /uniform/ strategy which does uniform sampling along an enumeration * allows different strategies to be mixed; for example one can exhaustively test all binary trees up to a certain size, filled with random integers. * complete separation between properties, generators, testing strategies and test execution methods
This sounds very interesting to me since I had a lot of trouble with changed test case distributions when switching from QuickCheck-1 to QuickCheck-2. It was mainly that tested numbers became much bigger in QuickCheck-2 and if I used the numbers as size of lists, then tests could not be run in reasonable time anymore. Thus I think more control over test-case generation is necessary. QuickCheck is Haskell-98 and thus is very portable. I see that GenCheck needs some more extensions - type families, multi-parameter type classes, what else?