# This file has been generated by Niv.
 
 let
 
   #
   # The fetchers. fetch_<type> fetches specs of type <type>.
   #
 
   fetch_file = pkgs: name: spec:
     let
       name' = sanitizeName name + "-src";
     in
       if spec.builtin or true then
         builtins_fetchurl { inherit (spec) url sha256; name = name'; }
       else
         pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
 
   fetch_tarball = pkgs: name: spec:
     let
       name' = sanitizeName name + "-src";
     in
       if spec.builtin or true then
         builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
       else
         pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
 
   fetch_git = name: spec:
     let
       ref =
         if spec ? ref then spec.ref else
           if spec ? branch then "refs/heads/${spec.branch}" else
             if spec ? tag then "refs/tags/${spec.tag}" else
               abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!";
     in
       builtins.fetchGit { url = spec.repo; inherit (spec) rev; inherit ref; };
 
   fetch_local = spec: spec.path;
 
   fetch_builtin-tarball = name: throw
     ''[${name}] The niv type "builtin-tarball" is deprecated. You should instead use `builtin = true`.
         $ niv modify ${name} -a type=tarball -a builtin=true'';
 
   fetch_builtin-url = name: throw
     ''[${name}] The niv type "builtin-url" will soon be deprecated. You should instead use `builtin = true`.
         $ niv modify ${name} -a type=file -a builtin=true'';
 
   #
   # Various helpers
   #
 
   # https://github.com/NixOS/nixpkgs/pull/83241/files#diff-c6f540a4f3bfa4b0e8b6bafd4cd54e8bR695
   sanitizeName = name:
     (
       concatMapStrings (s: if builtins.isList s then "-" else s)
         (
           builtins.split "[^[:alnum:]+._?=-]+"
             ((x: builtins.elemAt (builtins.match "\\.*(.*)" x) 0) name)
         )
     );
 
   # The set of packages used when specs are fetched using non-builtins.
   mkPkgs = sources: system:
     let
       sourcesNixpkgs =
         import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) { inherit system; };
       hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
       hasThisAsNixpkgsPath = <nixpkgs> == ./.;
     in
       if builtins.hasAttr "nixpkgs" sources
       then sourcesNixpkgs
       else if hasNixpkgsPath && ! hasThisAsNixpkgsPath then
         import <nixpkgs> {}
       else
         abort
           ''
             Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
             add a package called "nixpkgs" to your sources.json.
           '';
 
   # The actual fetching function.
   fetch = pkgs: name: spec:
 
     if ! builtins.hasAttr "type" spec then
       abort "ERROR: niv spec ${name} does not have a 'type' attribute"
     else if spec.type == "file" then fetch_file pkgs name spec
     else if spec.type == "tarball" then fetch_tarball pkgs name spec
     else if spec.type == "git" then fetch_git name spec
     else if spec.type == "local" then fetch_local spec
     else if spec.type == "builtin-tarball" then fetch_builtin-tarball name
     else if spec.type == "builtin-url" then fetch_builtin-url name
     else
       abort "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}";
 
   # If the environment variable NIV_OVERRIDE_${name} is set, then use
   # the path directly as opposed to the fetched source.
   replace = name: drv:
     let
       saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name;
       ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
     in
       if ersatz == "" then drv else
         # this turns the string into an actual Nix path (for both absolute and
         # relative paths)
         if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
 
   # Ports of functions for older nix versions
 
   # a Nix version of mapAttrs if the built-in doesn't exist
   mapAttrs = builtins.mapAttrs or (
     f: set: with builtins;
     listToAttrs (map (attr: { name = attr; value = f attr set.${attr}; }) (attrNames set))
   );
 
   # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295
   range = first: last: if first > last then [] else builtins.genList (n: first + n) (last - first + 1);
 
   # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257
   stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1));
 
   # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269
   stringAsChars = f: s: concatStrings (map f (stringToCharacters s));
   concatMapStrings = f: list: concatStrings (map f list);
   concatStrings = builtins.concatStringsSep "";
 
   # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331
   optionalAttrs = cond: as: if cond then as else {};
 
   # fetchTarball version that is compatible between all the versions of Nix
   builtins_fetchTarball = { url, name ? null, sha256 }@attrs:
     let
       inherit (builtins) lessThan nixVersion fetchTarball;
     in
       if lessThan nixVersion "1.12" then
         fetchTarball ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
       else
         fetchTarball attrs;
 
   # fetchurl version that is compatible between all the versions of Nix
   builtins_fetchurl = { url, name ? null, sha256 }@attrs:
     let
       inherit (builtins) lessThan nixVersion fetchurl;
     in
       if lessThan nixVersion "1.12" then
         fetchurl ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
       else
         fetchurl attrs;
 
   # Create the final "sources" from the config
   mkSources = config:
     mapAttrs (
       name: spec:
         if builtins.hasAttr "outPath" spec
         then abort
           "The values in sources.json should not have an 'outPath' attribute"
         else
           spec // { outPath = replace name (fetch config.pkgs name spec); }
     ) config.sources;
 
   # The "config" used by the fetchers
   mkConfig =
     { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
     , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile)
     , system ? builtins.currentSystem
     , pkgs ? mkPkgs sources system
     }: rec {
       # The sources, i.e. the attribute set of spec name to spec
       inherit sources;
 
       # The "pkgs" (evaluated nixpkgs) to use for e.g. non-builtin fetchers
       inherit pkgs;
     };
 
 in
 mkSources (mkConfig {}) // { __functor = _: settings: mkSources (mkConfig settings); }