Expose as a flake

[Mic92]

Currently its not possible to use this with nix develop because it internally re-imports nixpkgs:

error: --- EvalError --------------------------------------------------------------------------------- nix
at: (90:39) in file: /nix/store/ma3b77vjls3qrznwh66ix5ivvybx6003-source/pkgs/top-level/impure.nix

    89|                 else (if args ? localSystem then {}
    90|                       else { system = builtins.currentSystem; }) // localSystem;
      |                                       ^
    91| })

attribute 'currentSystem' missing
(use '--show-trace' to show detailed location information)
direnv: export +IN_NIX_SHELL ~PATH

[roberth]

It works fine if you import the modules directly. Not saying you should do that, but that means it's not far off.

[Mic92]

I don't think the modules can be imported directly. It's too tightly coupled too niv and inject overlays, which cannot be easily overwritten.

[roberth]

It's not that bad, but that's quite an experimental project anyway.

Let's focus on the problem here, which is probably the initialization of tools.

[lovesegfault]

@Myhlamaeus any chance you can rebase your PR?

[domenkozar]

I've closed that PR as it was out of date and not the approach I'd like to see merged - flake.nix shouldn't duplicate code from non-flake bits.

I'm going to start working towards flake support, starting with cleanups like #100

[domenkozar]

Bumping packages with more cleanup at #102

[domenkozar]

Barebone flake support at #103, but it's blocked on two issues.

I'd appreciate if a macOS user can help with #102

[domenkozar]

#103 is ready to be merged, I'd like someone that uses flakes to give it a try!

Exposing lib.run for all the heavy lifting!

[dhess]

I'm trying it out here:

https://github.com/hackworthltd/haskell-template/tree/pre-commit-hooks-flake

I'm probably being dense, but it's not clear to me out to use lib.run. This is what I've got, based on how we used to use it pre-flake:

https://github.com/hackworthltd/haskell-template/blob/4b66ab93e4ef4961e7ffff3298bfe8b6422fcf8e/flake.nix#L76

but I'm getting this error:

 nix-build -A hydraJobs.source-code-checks                                                                      /Volumes/src/dhess/haskell-template
error: attempt to call something which is not a function but a set

       at /nix/store/lrj3qxbgdpmdnlc2a9fh732vajdmqynb-source/flake.nix:76:9:

           75|         in
           76|         pre-commit-hooks-nix.lib.${system}.run {
             |         ^
           77|           src = ./.;
(use '--show-trace' to show detailed location information)

[domenkozar]

Oh, skip system on the lib output: pre-commit-hooks-nix.lib.run {

[dhess]

I tried that as well, but no:

 nix build .#hydraJobs.source-code-checks                                                                       /Volumes/src/dhess/haskell-template
warning: Git tree '/Volumes/src/dhess/haskell-template' is dirty
error: attribute 'run' missing

       at /nix/store/n1myzg0ssh4v6vc3xh475cv5hd93qcjc-source/flake.nix:76:9:

           75|         in
           76|         pre-commit-hooks-nix.lib.run {
             |         ^
           77|           src = ./.;
(use '--show-trace' to show detailed location information)

[domenkozar]

run wasn't exported. I've added a test for that.

You can try with pre-commit-hooks-nix.lib.${system}.run, I've made the system explicit.

[dhess]

Yes, this now works, thanks so much!

[domenkozar]

Merged, thanks!

[domenkozar]

Docs: https://github.com/cachix/pre-commit-hooks.nix#nix-flakes-support