normalize method

String normalize(String path)

path normalized to an absolute spelling: every separator becomes separator and every . and .. segment is resolved against the root driveRoot gives. Excess .. at the root are dropped; the spelling of the root itself is kept.

Implementation

String normalize(String path) {
  final String? root = driveRoot(path);
  final String head = root == null ? path : path.substring(root.length);
  final List<String> result = <String>[];
  for (final String segment in head.split(RegExp(r'[/\\]'))) {
    if (segment.isEmpty || segment == '.') {
      continue;
    }
    if (segment == '..') {
      if (result.isNotEmpty) {
        result.removeLast();
      }
      continue;
    }
    result.add(segment);
  }
  if (root == null) {
    return result.join(separator);
  }
  final String tail = result.join(separator);
  final bool rooted = root.endsWith(r'\') || root.endsWith('/');
  return rooted ? '$root$tail' : '$root$separator$tail';
}