public void CodePointEncodingTest()
 {
     using (var stream = new MemoryStream(4))
         using (var writer = new BinaryWriter(stream, Encoding.UTF8, true))
             using (var reader = new BinaryReader(stream, Encoding.UTF8, true))
             {
                 for (int i = 0; i <= 0x10FFFF; ++i)
                 {
                     writer.WriteCodePoint(i);
                     writer.Flush();
                     stream.Position = 0;
                     Assert.Equal(i, UnicodeInfo.ReadCodePoint(reader));
                     stream.Position = 0;
                 }
             }
 }