public void should_remove_callback()
{
var completionCallbackMock = new Mock<ICompletionCallback>();
var messageId = Guid.NewGuid();
_callbackRepository.RegisterCallback(messageId, completionCallbackMock.Object);
var callback = _callbackRepository.GetCallback(messageId);
Assert.AreEqual(completionCallbackMock.Object, callback);
_callbackRepository.RemoveCallback(messageId);
Assert.IsNull(_callbackRepository.GetCallback(messageId));
}