public void ReadInvalidUtf8()
{
MemoryStream ms = new MemoryStream();
CodedOutputStream output = CodedOutputStream.CreateInstance(ms);
uint tag = WireFormat.MakeTag(1, WireFormat.WireType.LengthDelimited);
output.WriteRawVarint32(tag);
output.WriteRawVarint32(1);
output.WriteRawBytes(new byte[] { 0x80 });
output.Flush();
ms.Position = 0;
CodedInputStream input = CodedInputStream.CreateInstance(ms);
uint testtag;
string ignored;
Assert.IsTrue(input.ReadTag(out testtag, out ignored));
Assert.AreEqual(tag, testtag);
string text = null;
input.ReadString(ref text);
Assert.AreEqual('\ufffd', text[0]);
}