| """ | |
| Patched ``BZ2File`` and ``LZMAFile`` to handle pickle protocol 5. | |
| """ | |
| from __future__ import annotations | |
| from pickle import PickleBuffer | |
| from pandas.compat._constants import PY310 | |
| try: | |
| import bz2 | |
| has_bz2 = True | |
| except ImportError: | |
| has_bz2 = False | |
| try: | |
| import lzma | |
| has_lzma = True | |
| except ImportError: | |
| has_lzma = False | |
| def flatten_buffer( | |
| b: bytes | bytearray | memoryview | PickleBuffer, | |
| ) -> bytes | bytearray | memoryview: | |
| """ | |
| Return some 1-D `uint8` typed buffer. | |
| Coerces anything that does not match that description to one that does | |
| without copying if possible (otherwise will copy). | |
| """ | |
| if isinstance(b, (bytes, bytearray)): | |
| return b | |
| if not isinstance(b, PickleBuffer): | |
| b = PickleBuffer(b) | |
| try: | |
| # coerce to 1-D `uint8` C-contiguous `memoryview` zero-copy | |
| return b.raw() | |
| except BufferError: | |
| # perform in-memory copy if buffer is not contiguous | |
| return memoryview(b).tobytes("A") | |
| if has_bz2: | |
| class BZ2File(bz2.BZ2File): | |
| if not PY310: | |
| def write(self, b) -> int: | |
| # Workaround issue where `bz2.BZ2File` expects `len` | |
| # to return the number of bytes in `b` by converting | |
| # `b` into something that meets that constraint with | |
| # minimal copying. | |
| # | |
| # Note: This is fixed in Python 3.10. | |
| return super().write(flatten_buffer(b)) | |
| if has_lzma: | |
| class LZMAFile(lzma.LZMAFile): | |
| if not PY310: | |
| def write(self, b) -> int: | |
| # Workaround issue where `lzma.LZMAFile` expects `len` | |
| # to return the number of bytes in `b` by converting | |
| # `b` into something that meets that constraint with | |
| # minimal copying. | |
| # | |
| # Note: This is fixed in Python 3.10. | |
| return super().write(flatten_buffer(b)) | |