def test_files
    # Handle the possibility that we have @test_suite_file but not
    # @test_files.  This will happen when an old gem is loaded via
    # YAML.
    if defined? @test_suite_file then
      @test_files = [@test_suite_file].flatten
      @test_suite_file = nil
    end
    if defined?(@test_files) and @test_files then
      @test_files
    else
      @test_files = []
    end
  end
#
Test files included in this gem.  You cannot append to this accessor, you
must assign to it.