Collections.addAll(set, elements);
    return set;
  }

  /**
   * Creates a <i>mutable</i> {@code HashSet} instance containing the given elements. A very thin
   * convenience for creating an empty set then calling {@link Collection#addAll} or {@link
   * Iterables#addAll}.
   *
   * <p><b>Note:</b> if mutability is not required and the elements are non-null, use {@link

    // figure space
    assertThat(parse("http://h/\u2007").encodedPath).isEqualTo("/%E2%80%87")
    // punctuation space
    assertThat(parse("http://h/\u2008").encodedPath).isEqualTo("/%E2%80%88")
    // thin space
    assertThat(parse("http://h/\u2009").encodedPath).isEqualTo("/%E2%80%89")
    // hair space
    assertThat(parse("http://h/\u200a").encodedPath).isEqualTo("/%E2%80%8A")
    // zero-width space