The "Hacking Agenda"

Involving @koengit @nick8325 @UlfNorell and @Rewbert:

Instances

• Arbitrary instances for everything in base (and other qc dependencies)
• Super clever TH magic to find all the types and generate properties
  • Enumerate all modules in base and get all the data types
  • Minimal: type check arbitrary @TheType
  • Better: Monomorphise and generate a properties to test the arbitrary instance
  • Manually exclude modules/types (to avoid writing clever rules for which
    types to support)
• See CollectDataTypes.hs and RunCollectDataTypes.hs.

Parallel fork

• Robert gives a nice presentation of what's going on

• We should decide on some design principles:

  • we care only about locally minimal counterexamples
  • we want the features module
  • we don't care about parallel quickcheck exploring sizes
    deterministically
  • we do care about sizes being explored in order small to big

API for test runners

• Tasty and HSpec install their own callbacks
  • Can we make PRs for them using Robert's new API?
  • Robert has the code, but needs some version juggling to work with different
    versions of QuickCheck.

Cleanup

• Drop ghc 7 support
• Clean up flag mess in cabal file
• Add MicroHs support
  • Lennart: "needs random numbers, this is hard!"

Read CollectDataTypes.hs and RunCollectDataTypes.hs first, then review the QuickCheck API compatibility needs for Tasty and HSpec. The agenda also lists design principles, Cabal cleanup, GHC 7 removal, and MicroHs support, but it does not define a single scope or completion condition.