anchor.diff:      var migratedLines = 0;
   
       for (var legacyPath in listFiles(dir)) {
  +      if (!_includeNonCoreLibs && _nonCoreLibs.any(legacyPath.startsWith)) {
  +        continue;
  +      }
  +
         files++;
         var lineCount = readFileLines(legacyPath).length;
         lines += lineCount;
  
positive.code: // TODO(rnystrom): Update this with numbers from migrating some language tests.
  const _linesPerDay = 24607;
  
  void main(List<String> arguments) {
    var totalFiles = 0;
    var totalLines = 0;
  
negative.code:   var migratedDays = migratedLines / _linesPerDay;
    var daysLeft = days - migratedDays;
  
    print("${label.padRight(12)} ${pad(migratedFiles, 4)}/${pad(files, 4)} "
        "files (${percent(migratedFiles, files)}%), "
        "${pad(migratedLines, 6)}/${pad(lines, 6)} "
        "lines (${percent(migratedLines, lines)}%), "
        "${pad(migratedDays.toStringAsFixed(2), 6)}/"
        "${pad(days.toStringAsFixed(2), 5)} "
        "days (${percent(migratedDays, days)}%), "
        "${pad(daysLeft.toStringAsFixed(2), 5)} days left");
  }
  