"""
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Patched ``BZ2File`` and ``LZMAFile`` to handle pickle protocol 5.
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"""
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from __future__ import annotations
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import bz2
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from pickle import PickleBuffer
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from pandas.compat._constants import PY310
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try:
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import lzma
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has_lzma = True
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except ImportError:
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has_lzma = False
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|
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def flatten_buffer(
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b: bytes | bytearray | memoryview | PickleBuffer,
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) -> bytes | bytearray | memoryview:
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"""
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Return some 1-D `uint8` typed buffer.
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Coerces anything that does not match that description to one that does
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without copying if possible (otherwise will copy).
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"""
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if isinstance(b, (bytes, bytearray)):
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return b
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if not isinstance(b, PickleBuffer):
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b = PickleBuffer(b)
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try:
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# coerce to 1-D `uint8` C-contiguous `memoryview` zero-copy
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return b.raw()
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except BufferError:
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# perform in-memory copy if buffer is not contiguous
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return memoryview(b).tobytes("A")
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|
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class BZ2File(bz2.BZ2File):
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if not PY310:
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def write(self, b) -> int:
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# Workaround issue where `bz2.BZ2File` expects `len`
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# to return the number of bytes in `b` by converting
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# `b` into something that meets that constraint with
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# minimal copying.
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#
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# Note: This is fixed in Python 3.10.
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return super().write(flatten_buffer(b))
|
|
|
if has_lzma:
|
|
class LZMAFile(lzma.LZMAFile):
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if not PY310:
|
|
def write(self, b) -> int:
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# Workaround issue where `lzma.LZMAFile` expects `len`
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# to return the number of bytes in `b` by converting
|
# `b` into something that meets that constraint with
|
# minimal copying.
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#
|
# Note: This is fixed in Python 3.10.
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return super().write(flatten_buffer(b))
|
