anchor.diff:          systemd.services.spacecookie = {
             preStart = ''
               mkdir -p ${gopherRoot}/directory
  -            echo "${fileContent}" > ${gopherRoot}/${fileName}
  +            printf "%s" "${fileContent}" > ${gopherRoot}/${fileName}
             '';
           };
   
  
positive.code:         };
        };
  
        client = {};
      };
  
      testScript = ''
        start_all()
        ${gopherHost}.wait_for_open_port(70)
        ${gopherHost}.wait_for_unit("spacecookie.service")
        client.wait_for_unit("network.target")
  
        fileResponse = client.succeed("curl -f -s gopher://${gopherHost}//${fileName}")
  
        # the file response should return our created file exactly
        if not (fileResponse == "${fileContent}\n"):
            raise Exception("Unexpected file response")
  
        # sanity check on the directory listing: we serve a directory and a file
        # via gopher, so the directory listing should have exactly two entries,
        # one with gopher file type 0 (file) and one with file type 1 (directory).
        dirResponse = client.succeed("curl -f -s gopher://${gopherHost}")
        dirEntries = [l[0] for l in dirResponse.split("\n") if len(l) > 0]
        dirEntries.sort()
  
  
negative.code: let
    gopherRoot   = "/tmp/gopher";
    gopherHost   = "gopherd";
    gopherClient = "client";
    fileContent  = "Hello Gopher!\n";
    fileName     = "file.txt";
  in
    import ./make-test-python.nix ({...}: {
      name = "spacecookie";
  