Add a callHackage variant that doesn't require all-cabal-hashes

[mightybyte]

Motivation for this change

Because callHackage uses all-cabal-hashes to avoid requiring the user to specify a hash, it does not work for any package versions that have been uploaded after the version of all-cabal-hashes that you happen to have. In my experience this means that probably greater than half the time callHackage doesn't work for me, and I have to fall back to fetchFromGitHub. This is a pretty poor user experience and is also less reliable because github packages can be deleted, but hackage releases cannot.

This function works for any package that has been released on hackage. I have been using it recently in some of my production projects and it has been working fine. It would be really nice to have it available in nixpkgs.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS)
• 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 nox --run "nox-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)
• Assured whether relevant documentation is up to date
• Fits CONTRIBUTING.md.

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[cdepillabout]

This looks good to me.

I've wanted a function like this before. It'll be great to have it in nixpkgs.

[shlevy]

LGTM other than @puffnfresh's comment.

[mightybyte]

I responded to @puffnfresh above. Also, regarding the name...I'm definitely not stuck on this name. I'm not crazy about callHackage' though, because I tend to think primes aren't visually distinct enough. Open to better suggestions here.

[mightybyte]

I've tested this and verified that it works with a real external package. Should be ready to merge now.

[ElvishJerricco]

This should probably have some kind of support for revisions, like a revision number arg and a cabal file sha arg.

[ElvishJerricco]

It'd also be really cool to have some way to use this from packageSourceOverrides

[mightybyte]

@ElvishJerricco Agreed, although that requires a bit more work because you have to download the tarball and replace the cabal file inside it with the one for the revision. In practice, the lack of revision support hasn't bothered me too much yet because revisions can only make changes to metadata and that can usually be accomplished with doJailbreak. There may be places where this isn't sufficient and proper revision support is needed, but it's been good enough for me thus far.