void TestEscape()
{
var yw = new YAMLWriter(Console.Out, 0, 60);
Is(yw.Escape("\u0087"), "\"\\u0087\"");
Is(yw.Escape("\ufffe"), "\"\\ufffe\"");
Is(yw.Escape("\ud900"), "\"\\ud900\"");
Is(yw.Escape("\u0085\uffff"), "\"\\N\\uffff\"");
}