craftbeerpi4-pione/venv/lib/python3.8/site-packages/pandas/compat/pickle_compat.py
2021-01-30 22:29:33 +01:00

280 lines
7.7 KiB
Python

"""
Support pre-0.12 series pickle compatibility.
"""
import contextlib
import copy
import io
import pickle as pkl
from typing import TYPE_CHECKING, Optional
import warnings
from pandas._libs.tslibs import BaseOffset
from pandas import Index
if TYPE_CHECKING:
from pandas import DataFrame, Series
def load_reduce(self):
stack = self.stack
args = stack.pop()
func = stack[-1]
if len(args) and type(args[0]) is type:
n = args[0].__name__ # noqa
try:
stack[-1] = func(*args)
return
except TypeError as err:
# If we have a deprecated function,
# try to replace and try again.
msg = "_reconstruct: First argument must be a sub-type of ndarray"
if msg in str(err):
try:
cls = args[0]
stack[-1] = object.__new__(cls)
return
except TypeError:
pass
elif args and issubclass(args[0], BaseOffset):
# TypeError: object.__new__(Day) is not safe, use Day.__new__()
cls = args[0]
stack[-1] = cls.__new__(*args)
return
raise
_sparse_msg = """\
Loading a saved '{cls}' as a {new} with sparse values.
'{cls}' is now removed. You should re-save this dataset in its new format.
"""
class _LoadSparseSeries:
# To load a SparseSeries as a Series[Sparse]
# https://github.com/python/mypy/issues/1020
# error: Incompatible return type for "__new__" (returns "Series", but must return
# a subtype of "_LoadSparseSeries")
def __new__(cls) -> "Series": # type: ignore
from pandas import Series
warnings.warn(
_sparse_msg.format(cls="SparseSeries", new="Series"),
FutureWarning,
stacklevel=6,
)
return Series(dtype=object)
class _LoadSparseFrame:
# To load a SparseDataFrame as a DataFrame[Sparse]
# https://github.com/python/mypy/issues/1020
# error: Incompatible return type for "__new__" (returns "DataFrame", but must
# return a subtype of "_LoadSparseFrame")
def __new__(cls) -> "DataFrame": # type: ignore
from pandas import DataFrame
warnings.warn(
_sparse_msg.format(cls="SparseDataFrame", new="DataFrame"),
FutureWarning,
stacklevel=6,
)
return DataFrame()
# If classes are moved, provide compat here.
_class_locations_map = {
("pandas.core.sparse.array", "SparseArray"): ("pandas.core.arrays", "SparseArray"),
# 15477
("pandas.core.base", "FrozenNDArray"): ("numpy", "ndarray"),
("pandas.core.indexes.frozen", "FrozenNDArray"): ("numpy", "ndarray"),
("pandas.core.base", "FrozenList"): ("pandas.core.indexes.frozen", "FrozenList"),
# 10890
("pandas.core.series", "TimeSeries"): ("pandas.core.series", "Series"),
("pandas.sparse.series", "SparseTimeSeries"): (
"pandas.core.sparse.series",
"SparseSeries",
),
# 12588, extensions moving
("pandas._sparse", "BlockIndex"): ("pandas._libs.sparse", "BlockIndex"),
("pandas.tslib", "Timestamp"): ("pandas._libs.tslib", "Timestamp"),
# 18543 moving period
("pandas._period", "Period"): ("pandas._libs.tslibs.period", "Period"),
("pandas._libs.period", "Period"): ("pandas._libs.tslibs.period", "Period"),
# 18014 moved __nat_unpickle from _libs.tslib-->_libs.tslibs.nattype
("pandas.tslib", "__nat_unpickle"): (
"pandas._libs.tslibs.nattype",
"__nat_unpickle",
),
("pandas._libs.tslib", "__nat_unpickle"): (
"pandas._libs.tslibs.nattype",
"__nat_unpickle",
),
# 15998 top-level dirs moving
("pandas.sparse.array", "SparseArray"): (
"pandas.core.arrays.sparse",
"SparseArray",
),
("pandas.sparse.series", "SparseSeries"): (
"pandas.compat.pickle_compat",
"_LoadSparseSeries",
),
("pandas.sparse.frame", "SparseDataFrame"): (
"pandas.core.sparse.frame",
"_LoadSparseFrame",
),
("pandas.indexes.base", "_new_Index"): ("pandas.core.indexes.base", "_new_Index"),
("pandas.indexes.base", "Index"): ("pandas.core.indexes.base", "Index"),
("pandas.indexes.numeric", "Int64Index"): (
"pandas.core.indexes.numeric",
"Int64Index",
),
("pandas.indexes.range", "RangeIndex"): ("pandas.core.indexes.range", "RangeIndex"),
("pandas.indexes.multi", "MultiIndex"): ("pandas.core.indexes.multi", "MultiIndex"),
("pandas.tseries.index", "_new_DatetimeIndex"): (
"pandas.core.indexes.datetimes",
"_new_DatetimeIndex",
),
("pandas.tseries.index", "DatetimeIndex"): (
"pandas.core.indexes.datetimes",
"DatetimeIndex",
),
("pandas.tseries.period", "PeriodIndex"): (
"pandas.core.indexes.period",
"PeriodIndex",
),
# 19269, arrays moving
("pandas.core.categorical", "Categorical"): ("pandas.core.arrays", "Categorical"),
# 19939, add timedeltaindex, float64index compat from 15998 move
("pandas.tseries.tdi", "TimedeltaIndex"): (
"pandas.core.indexes.timedeltas",
"TimedeltaIndex",
),
("pandas.indexes.numeric", "Float64Index"): (
"pandas.core.indexes.numeric",
"Float64Index",
),
("pandas.core.sparse.series", "SparseSeries"): (
"pandas.compat.pickle_compat",
"_LoadSparseSeries",
),
("pandas.core.sparse.frame", "SparseDataFrame"): (
"pandas.compat.pickle_compat",
"_LoadSparseFrame",
),
}
# our Unpickler sub-class to override methods and some dispatcher
# functions for compat and uses a non-public class of the pickle module.
# error: Name 'pkl._Unpickler' is not defined
class Unpickler(pkl._Unpickler): # type: ignore
def find_class(self, module, name):
# override superclass
key = (module, name)
module, name = _class_locations_map.get(key, key)
return super().find_class(module, name)
Unpickler.dispatch = copy.copy(Unpickler.dispatch)
Unpickler.dispatch[pkl.REDUCE[0]] = load_reduce
def load_newobj(self):
args = self.stack.pop()
cls = self.stack[-1]
# compat
if issubclass(cls, Index):
obj = object.__new__(cls)
else:
obj = cls.__new__(cls, *args)
self.stack[-1] = obj
Unpickler.dispatch[pkl.NEWOBJ[0]] = load_newobj
def load_newobj_ex(self):
kwargs = self.stack.pop()
args = self.stack.pop()
cls = self.stack.pop()
# compat
if issubclass(cls, Index):
obj = object.__new__(cls)
else:
obj = cls.__new__(cls, *args, **kwargs)
self.append(obj)
try:
Unpickler.dispatch[pkl.NEWOBJ_EX[0]] = load_newobj_ex
except (AttributeError, KeyError):
pass
def load(fh, encoding: Optional[str] = None, is_verbose: bool = False):
"""
Load a pickle, with a provided encoding,
Parameters
----------
fh : a filelike object
encoding : an optional encoding
is_verbose : show exception output
"""
try:
fh.seek(0)
if encoding is not None:
up = Unpickler(fh, encoding=encoding)
else:
up = Unpickler(fh)
up.is_verbose = is_verbose
return up.load()
except (ValueError, TypeError):
raise
def loads(
bytes_object: bytes,
*,
fix_imports: bool = True,
encoding: str = "ASCII",
errors: str = "strict",
):
"""
Analogous to pickle._loads.
"""
fd = io.BytesIO(bytes_object)
return Unpickler(
fd, fix_imports=fix_imports, encoding=encoding, errors=errors
).load()
@contextlib.contextmanager
def patch_pickle():
"""
Temporarily patch pickle to use our unpickler.
"""
orig_loads = pkl.loads
try:
pkl.loads = loads
yield
finally:
pkl.loads = orig_loads