hackage2nix: fromString: "_type" is not a valid PackageVersionConstraint

[wolfgangwalther]

Currently trying to mark packages on haskell-updates as broken, but running hackage2nix now results in:

hackage2nix: fromString: "_type" is not a valid PackageVersionConstraint
CallStack (from HasCallStack):
  error, called at src/Distribution/Nixpkgs/Haskell/OrphanInstances.hs:89:32 in cabal2nix-2.20.1-LIrlgcX3ajCmHtwEJXoey:Distribution.Nixpkgs.Haskell.OrphanInstances
HasCallStack backtrace:
  collectBacktraces, called at libraries/ghc-internal/src/GHC/Internal/Exception.hs:169:13 in ghc-internal:GHC.Internal.Exception
  toExceptionWithBacktrace, called at libraries/ghc-internal/src/GHC/Internal/Exception.hs:204:5 in ghc-internal:GHC.Internal.Exception
  error, called at src/Distribution/Nixpkgs/Haskell/OrphanInstances.hs:89:32 in cabal2nix-2.20.1-LIrlgcX3ajCmHtwEJXoey:Distribution.Nixpkgs.Haskell.OrphanInstances

Will not mark _type as broken for now.

[sternenseemann]

This problem occurred to me yesterday as well. I'm not sure if we want to track attribute names or Hackage package names in the configuration files. In theory we have both available in Nixpkgs since pname is the Hackage package name.

[wolfgangwalther]

Ah, so I need to change this to type instead?

[sternenseemann]

Yes, that should work fine. PackageVersionConstraint is basically a Cabal package name and optionally version constraints, so it fails to parse because underscores are not allowed.

[sternenseemann]

W.r.t. transitive-broken.yaml, this issue should be addressed by NixOS/nixpkgs#488285. We probably need to implement a similar change for hydra-report.hs and friends.