public void Initialize()
{
_factoryStub = MockRepository.GenerateStub<IStreamFactory>();
_textWriterMock = MockRepository.GenerateMock<TextWriter>();
_streamMock = MockRepository.GenerateMock<Stream>();
_factoryStub.Stub(f => f.CreateDictionaryStreamWriter($"{Filepath}.{CompressingIndexSerializer.DictionaryFileSuffix}"))
.Return(_textWriterMock);
_factoryStub.Stub(f => f.CreateDocumentIdsStream($"{Filepath}.{CompressingIndexSerializer.PostingsFileSuffix}", FileMode.Create)).Return(_streamMock);
_encoderStub = MockRepository.GenerateStub<INumberEncoder>();
_numberLengthReducerStub = MockRepository.GenerateStub<INumberLengthReducer>();
_target = new CompressingIndexSerializer(_factoryStub, _encoderStub, _numberLengthReducerStub);
}