1require 'test/unit'
2require "-test-/string/string"
3
4class Test_StrEncAssociate < Test::Unit::TestCase
5  def test_frozen
6    s = Bug::String.new("abc")
7    s.force_encoding(Encoding::US_ASCII)
8    s.freeze
9    assert_raise(RuntimeError) {s.associate_encoding!(Encoding::US_ASCII)}
10    assert_raise(RuntimeError) {s.associate_encoding!(Encoding::UTF_8)}
11  end
12end
13