shell-commands.nix

{ lib, symlinkJoin, writeShellScriptBin }:
name:
{ build ? { script = ''eval "$buildPhase"''; description = "Run the build."; }
, check ? { script = ''eval "$checkPhase"''; description = "Run the checks/test."; }
, run ? { script = "echo '🏃 \"run\" not supported'"; show = false; }
, format ? { script = "echo '📃 \"format\" not supported'"; show = false; }
, ...
}@commands:
let
  shellCommandHelpText = descriptions: ''
    esc=$(printf '\e[')
    ${builtins.concatStringsSep "\n" (lib.mapAttrsToList (name: desc:
      ''echo "  ''${esc}32m${name}''${esc}0m ''${esc}33m${desc.args}''${esc}0m" ${if desc.description != "" then '';echo -e "    ${builtins.replaceStrings ["\n"] ["\n    "] desc.description}"'' else ""}'')
      (descriptions // {
        shellHelp = {
          description = "Print this help text";
          args = "";
        };
      }))}
  '';

  # need to wrangle a little bit to get the descriptions for the shell message
  allCommands = commands // { inherit build check run format; };
  inner = cmds: symlinkJoin {
    name = "${name}-shell-commands";
    paths = (lib.mapAttrsToList
      (command: script: writeShellScriptBin command ''
        envDir=$(mktemp -d -t shell-command-env.XXXXXX)

        export 2>/dev/null >| "$envDir"/shell-env

        # source setup to get functions like genericBuild for example
        # as users might expect this to exist
        NIX_BUILD_TOP=$envDir source $stdenv/setup > /dev/null

        # reset the shell env
        source "$envDir"/shell-env

        # need to set this to be able to have local inputs
        export NIX_ENFORCE_PURITY=0

        rm -rf "$envDir"
        set -euo pipefail
        ${if builtins.isAttrs script then script.script or "" else script}
      '')
      cmds) ++ [
      (writeShellScriptBin "shellHelp" ''
        ${shellCommandHelpText (builtins.mapAttrs
        (_: value:
          {
            description = if builtins.isAttrs value then value.description or "" else "";
            args = if builtins.isAttrs value then value.args or "" else "";
          }
        )
          (lib.filterAttrs (_: value:
            if builtins.isAttrs value then
              value.show or true
            else
              true)
            cmds)
        )
         }
      '')
    ];
  };
in
lib.makeOverridable inner allCommands