in lib/src/utils.dart [18:24]
bool isDriveLetter(String path, int index) {
if (path.length < index + 2) return false;
if (!isAlphabetic(path.codeUnitAt(index))) return false;
if (path.codeUnitAt(index + 1) != chars.colon) return false;
if (path.length == index + 2) return true;
return path.codeUnitAt(index + 2) == chars.slash;
}