{dots, "...", -1, []string{"1", ".2", ".3", ".4"}},
	{faces, "☹", -1, []string{"☺☻", ""}},
	{faces, "~", -1, []string{faces}},
	{faces, "", -1, []string{"☺", "☻", "☹"}},
	{"1 2 3 4", " ", 3, []string{"1", "2", "3 4"}},
	{"1 2", " ", 3, []string{"1", "2"}},
	{"123", "", 2, []string{"1", "23"}},
	{"123", "", 17, []string{"1", "2", "3"}},
	{"bT", "T", math.MaxInt / 4, []string{"b", ""}},
	{"\xff-\xff", "", -1, []string{"\xff", "-", "\xff"}},

    }
  }

  /**
   * Returns the set of all subsets of {@code set} of size {@code size}. For example, {@code
   * combinations(ImmutableSet.of(1, 2, 3), 2)} returns the set {@code {{1, 2}, {1, 3}, {2, 3}}}.
   *
   * <p>Elements appear in these subsets in the same iteration order as they appeared in the input
   * set. The order in which these subsets appear in the outer set is undefined.
   *