haskellPackages.{hedgehog-classes, hgeometry, hgeometry-combinatorial}: unbreak

[sternenseemann]

hedgehog has a too strict bound on semirings which breaks its build.
Unfortunately we need to patch the cabal source since the bound is
conditional.

Motivation for this change

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[cdepillabout]

Looks good, these all compile!

[sternenseemann]

@cdepillabout Upstream indicates that with our setup, the doctests for hgeometry-combinatorial wouldn't work. Seems like they are having trouble linking against the cbits of the base package: noinia/hgeometry#132 (comment)

You know more about doctests than me, any chance we can make them work?

[cdepillabout]

@sternenseemann In my experience, plain doctest is pretty unreliable, which is why most libraries have switched to using cabal-doctest.

However, I don't know what could be causing the error you're seeing in noinia/hgeometry#132.

My only guess is that https://github.com/noinia/hgeometry/blob/1aa137819b8b959f842adf7cd7172bbf5ec20adf/hgeometry-combinatorial/doctests.hs doesn't specify anything about c-sources, while the .cabal file does: https://github.com/noinia/hgeometry/blob/1aa137819b8b959f842adf7cd7172bbf5ec20adf/hgeometry-combinatorial/hgeometry-combinatorial.cabal#L198-L199. I imagine that GHC (well, doctest) doesn't have any way of figuring this out for itself, while cabal does.

[sternenseemann]

Maybe, I'll investigate again, when I feel like it; adding c-sources for the tests doesn't help which is what I tried so far. Losing the test suite is not too bad I guess.