anchor.diff:  , python3
   , cmake
   , fishPlugins
  +, procps
   
   , runCommand
   , writeText
  
positive.code:       sha256 = "sha256-TwKT7Z9qa3fkfUHvq+YvMxnobvyL+DzFhzMET7xvkhE=";
      };
  
      nativeBuildInputs = [
        cmake
      ];
  
negative.code:       groff
        gettext
      ] ++ lib.optional (!stdenv.isDarwin) man-db;
  
      doCheck = true;
  
      checkInputs = [
        coreutils
        (python3.withPackages(ps: [ps.pexpect]))
        procps
      ];
  
      checkPhase = ''
        make test
      '';
  
      postInstall = with lib; ''
        sed -r "s|command grep|command ${gnugrep}/bin/grep|" \
  