cloneSet<E> method

@override Set<E> cloneSet<E>(Set<E> source)

Return a deep-cloned Set.

When doTypedClone is true the returned set preserves element types and performs typed cloning of elements. Typed cloning will throw UnsupportedTypedCloneException if a nested Map is encountered.

On dynamic cloning preserves the concrete Set implementation (e.g. LinkedHashSet, HashSet, UnmodifiableSetView). Typed nested cloning will erase generics at runtime; the typed Set cloning implementation relies on toSet() to preserve the runtime element type of the original set, but not underlying implementation.

Implementation

@override
Set<E> cloneSet<E>(Set<E> source) {
  final isUnmodifiable = source is UnmodifiableSetView<E>;
  final Set<E> cloned;
  if (doTypedClone) {
    cloned = source.toSet();
    cloned.clear();
    for (final e in source) {
      cloned.add(_cloneValueTyped(e));
    }
  } else {
    cloned = switch (source) {
      LinkedHashSet<E>() => <E>{for (final e in source) cloneValue(e)},
      HashSet<E>() => HashSet<E>.of(source.map((e) => cloneValue(e))),
      _ => <E>{for (final e in source) cloneValue(e)},
    };
  }
  return isUnmodifiable ? UnmodifiableSetView<E>(cloned) : cloned;
}