How do I match the right Cabal spec with each resolver in my Travis CI builds?
问题 After updating my Haskell package's .cabal file to Cabal 2.2, most of my Travis CI builds with resolvers older than LTS 12.9 fail with: This package description follows version 2.2 of the Cabal specification. This tool only supports up to version XX.XX.XX. where the version varies depending on the resolver specified in my .travis.yaml. It seems that for each resolver I need to specify a different Cabal version In fact, because of Cabal spec changes, I appear to need a different .cabal file