# File test/test_sexp.rb, line 190
  def test_gsub
    assert_equal s(:c), s().gsub(s(), s(:c))
    assert_equal s(:c), s(:b).gsub(s(:b), s(:c))
    assert_equal s(:a), s(:a).gsub(s(:b), s(:c))
    assert_equal s(:a, s(:c)), s(:a, s(:b)).gsub(s(:b), s(:c))

    assert_equal(s(:a, s(:c), s(:c)),
                 s(:a, s(:b), s(:b)).gsub(s(:b), s(:c)))
    assert_equal(s(:a, s(:c), s(:a, s(:c))),
                 s(:a, s(:b), s(:a, s(:b))).gsub(s(:b), s(:c)))
  end