niv/nix/sources.nix

# This file has been generated by Niv.

# A record, from name to path, of the third-party packages
with rec
{
  pkgs =
    if hasNixpkgsPath
    then
        if hasThisAsNixpkgsPath
        then import (builtins_fetchTarball { inherit (sources_nixpkgs) url sha256; }) {}
        else import <nixpkgs> {}
    else
        import (builtins_fetchTarball { inherit (sources_nixpkgs) url sha256; }) {};

  sources_nixpkgs =
    if builtins.hasAttr "nixpkgs" sources
    then sources.nixpkgs
    else abort
    ''
        Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
        add a package called "nixpkgs" to your sources.json.
    '';

  # fetchTarball version that is compatible between all the versions of Nix
  builtins_fetchTarball =
      { url, sha256 }@attrs:
      let
        inherit (builtins) lessThan nixVersion fetchTarball;
      in
        if lessThan nixVersion "1.12" then
          fetchTarball { inherit url; }
        else
          fetchTarball attrs;

  # fetchurl version that is compatible between all the versions of Nix
  builtins_fetchurl =
      { url, sha256 }@attrs:
      let
        inherit (builtins) lessThan nixVersion fetchurl;
      in
        if lessThan nixVersion "1.12" then
          fetchurl { inherit url; }
        else
          fetchurl attrs;

  # A wrapper around pkgs.fetchzip that has inspectable arguments,
  # annoyingly this means we have to specify them
  fetchzip = { url, sha256 }@attrs: pkgs.fetchzip attrs;

  hasNixpkgsPath = (builtins.tryEval <nixpkgs>).success;
  hasThisAsNixpkgsPath =
    (builtins.tryEval <nixpkgs>).success && <nixpkgs> == ./.;

  sources = builtins.fromJSON (builtins.readFile ./sources.json);

  mapAttrs = builtins.mapAttrs or
    (f: set: with builtins;
      listToAttrs (map (attr: { name = attr; value = f attr set.${attr}; }) (attrNames set)));

  # borrowed from nixpkgs
  functionArgs = f: f.__functionArgs or (builtins.functionArgs f);
  callFunctionWith = autoArgs: f: args:
    let auto = builtins.intersectAttrs (functionArgs f) autoArgs;
    in f (auto // args);

  getFetcher = spec:
    let fetcherName =
      if builtins.hasAttr "type" spec
      then builtins.getAttr "type" spec
      else "builtin-tarball";
    in builtins.getAttr fetcherName {
      "tarball" = fetchzip;
      "builtin-tarball" = builtins_fetchTarball;
      "file" = pkgs.fetchurl;
      "builtin-url" = builtins_fetchurl;
    };
};
# NOTE: spec must _not_ have an "outPath" attribute
mapAttrs (_: spec:
  if builtins.hasAttr "outPath" spec
  then abort
    "The values in sources.json should not have an 'outPath' attribute"
  else
    if builtins.hasAttr "url" spec && builtins.hasAttr "sha256" spec
    then
      spec //
      { outPath = callFunctionWith spec (getFetcher spec) { }; }
    else spec
  ) sources