def split_buffer(stream, splitter=None, decoder=lambda a: a):
    """Given a generator which yields strings and a splitter function,
    joins all input, splits on the separator and yields each chunk.

    Unlike string.split(), each chunk includes the trailing
    separator, except for the last one if none was found on the end
    of the input.
    """
    splitter = splitter or line_splitter
    buffered = six.text_type('')

    for data in stream_as_text(stream):
        buffered += data
        while True:
            buffer_split = splitter(buffered)
            if buffer_split is None:
                break

            item, buffered = buffer_split
            yield item

    if buffered:
        yield decoder(buffered)
Given a generator which yields strings and a splitter function,
    joins all input, splits on the separator and yields each chunk.

    Unlike string.split(), each chunk includes the trailing
    separator, except for the last one if none was found on the end
    of the input.