Lucas, it is indeed impossible for peek() to return more than the buffer
size and remain compatible with non-seekable raw streams. That's why it
/never/ returns more than the buffer size.
As for the fact that peek() doesn't behave as documented, I disagree.
Here is what the docstring says:
"""Returns buffered bytes without advancing the position.
The argument indicates a desired minimal number of bytes; we
do at most one raw read to satisfy it. We never return more
than self.buffer_size.
"""
Please note : "a desired /minimal/ number of bytes" (minimal, not
maximal). Furthermore, "We never return more than self.buffer_size." The
behaviour looks ok to me.