anchor.diff:  %% These macros assume there's a bound variable called Verb.
   -define(VERB(Fmt),       if Verb -> io:format(Fmt      ); true -> ok end).
   -define(VERB(Fmt, Args), if Verb -> io:format(Fmt, Args); true -> ok end).
  +
  +-ifdef(TEST).
  +-compile(export_all).
  +-endif. % TEST
   
   -export([repair_cp/4, repair_ap/6]).
   
  
positive.code: mbytes(Size) ->
      lists:flatten(io_lib:format("~.1.0f", [max(0.1, Size / (1024*1024))])).
  
  
negative.code: %%     verb(" done\n", []),
  %%     ok.
  
  %% copy_file_proc_checksum_fun(File, SrcS, DstS, _Verbose) ->
  %%     fun(<<OffsetHex:16/binary, " ", LenHex:8/binary, " ",
  %%           CSumHex:32/binary, "\n">>) ->
  %%             <<Len:32/big>> = hexstr_to_bin(LenHex),
  %%             DownloadChunkBin = <<OffsetHex/binary, " ", LenHex/binary, " ",
  %%                                  File/binary, "\n">>,
  %%             [Chunk] = escript_download_chunks(SrcS, {{{DownloadChunkBin}}},
  %%                                               fun(_) -> ok end),
  %%             CSum = hexstr_to_bin(CSumHex),
  %%             CSum2 = checksum(Chunk),
  %%             if Len == byte_size(Chunk), CSum == CSum2 ->
  %%                     {_,_,_} = upload_chunk_write(DstS, OffsetHex, File, Chunk),
  %%                     ok;
  %%                true ->
  %%                     io:format("ERROR: ~s ~s ~s csum/size error\n",
  %%                               [File, OffsetHex, LenHex]),
  %%                     error
  %%             end;
  %%        (_Else) ->
  %%             ok
  %%     end.
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  file_folder(Fun, Acc, Path) ->
  