public void TestClear()
{
var output = new OutputBuilder().Append(originalMessage);
var outputBuilderType = output.GetType();
var bufferPos = outputBuilderType.GetField("bufferPos", BindingFlags.Instance | BindingFlags.NonPublic);
Assert.AreEqual(originalMessage.Length, bufferPos.GetValue(output));
output.Clear();
Assert.AreEqual(0, bufferPos.GetValue(output));
}