8th day of python challenges 111-117

This commit is contained in:
abd.shallal
2019-08-04 15:26:35 +03:00
parent b04c1b055f
commit 627802c383
3215 changed files with 760227 additions and 491 deletions

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from .array import JSONArray, JSONDtype, make_data
__all__ = ["JSONArray", "JSONDtype", "make_data"]

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"""Test extension array for storing nested data in a pandas container.
The JSONArray stores lists of dictionaries. The storage mechanism is a list,
not an ndarray.
Note:
We currently store lists of UserDicts. Pandas has a few places
internally that specifically check for dicts, and does non-scalar things
in that case. We *want* the dictionaries to be treated as scalars, so we
hack around pandas by using UserDicts.
"""
from collections import UserDict, abc
import itertools
import numbers
import random
import string
import sys
import numpy as np
from pandas.core.dtypes.base import ExtensionDtype
from pandas.core.arrays import ExtensionArray
class JSONDtype(ExtensionDtype):
type = abc.Mapping
name = "json"
na_value = UserDict()
@classmethod
def construct_array_type(cls):
"""Return the array type associated with this dtype
Returns
-------
type
"""
return JSONArray
@classmethod
def construct_from_string(cls, string):
if string == cls.name:
return cls()
else:
raise TypeError("Cannot construct a '{}' from '{}'".format(cls, string))
class JSONArray(ExtensionArray):
dtype = JSONDtype()
__array_priority__ = 1000
def __init__(self, values, dtype=None, copy=False):
for val in values:
if not isinstance(val, self.dtype.type):
raise TypeError("All values must be of type " + str(self.dtype.type))
self.data = values
# Some aliases for common attribute names to ensure pandas supports
# these
self._items = self._data = self.data
# those aliases are currently not working due to assumptions
# in internal code (GH-20735)
# self._values = self.values = self.data
@classmethod
def _from_sequence(cls, scalars, dtype=None, copy=False):
return cls(scalars)
@classmethod
def _from_factorized(cls, values, original):
return cls([UserDict(x) for x in values if x != ()])
def __getitem__(self, item):
if isinstance(item, numbers.Integral):
return self.data[item]
elif isinstance(item, np.ndarray) and item.dtype == "bool":
return self._from_sequence([x for x, m in zip(self, item) if m])
elif isinstance(item, abc.Iterable):
# fancy indexing
return type(self)([self.data[i] for i in item])
else:
# slice
return type(self)(self.data[item])
def __setitem__(self, key, value):
if isinstance(key, numbers.Integral):
self.data[key] = value
else:
if not isinstance(value, (type(self), abc.Sequence)):
# broadcast value
value = itertools.cycle([value])
if isinstance(key, np.ndarray) and key.dtype == "bool":
# masking
for i, (k, v) in enumerate(zip(key, value)):
if k:
assert isinstance(v, self.dtype.type)
self.data[i] = v
else:
for k, v in zip(key, value):
assert isinstance(v, self.dtype.type)
self.data[k] = v
def __len__(self):
return len(self.data)
@property
def nbytes(self):
return sys.getsizeof(self.data)
def isna(self):
return np.array([x == self.dtype.na_value for x in self.data], dtype=bool)
def take(self, indexer, allow_fill=False, fill_value=None):
# re-implement here, since NumPy has trouble setting
# sized objects like UserDicts into scalar slots of
# an ndarary.
indexer = np.asarray(indexer)
msg = (
"Index is out of bounds or cannot do a "
"non-empty take from an empty array."
)
if allow_fill:
if fill_value is None:
fill_value = self.dtype.na_value
# bounds check
if (indexer < -1).any():
raise ValueError
try:
output = [
self.data[loc] if loc != -1 else fill_value for loc in indexer
]
except IndexError:
raise IndexError(msg)
else:
try:
output = [self.data[loc] for loc in indexer]
except IndexError:
raise IndexError(msg)
return self._from_sequence(output)
def copy(self):
return type(self)(self.data[:])
def astype(self, dtype, copy=True):
# NumPy has issues when all the dicts are the same length.
# np.array([UserDict(...), UserDict(...)]) fails,
# but np.array([{...}, {...}]) works, so cast.
# needed to add this check for the Series constructor
if isinstance(dtype, type(self.dtype)) and dtype == self.dtype:
if copy:
return self.copy()
return self
return np.array([dict(x) for x in self], dtype=dtype, copy=copy)
def unique(self):
# Parent method doesn't work since np.array will try to infer
# a 2-dim object.
return type(self)(
[dict(x) for x in list({tuple(d.items()) for d in self.data})]
)
@classmethod
def _concat_same_type(cls, to_concat):
data = list(itertools.chain.from_iterable([x.data for x in to_concat]))
return cls(data)
def _values_for_factorize(self):
frozen = self._values_for_argsort()
if len(frozen) == 0:
# _factorize_array expects 1-d array, this is a len-0 2-d array.
frozen = frozen.ravel()
return frozen, ()
def _values_for_argsort(self):
# Disable NumPy's shape inference by including an empty tuple...
# If all the elemnts of self are the same size P, NumPy will
# cast them to an (N, P) array, instead of an (N,) array of tuples.
frozen = [()] + [tuple(x.items()) for x in self]
return np.array(frozen, dtype=object)[1:]
def make_data():
# TODO: Use a regular dict. See _NDFrameIndexer._setitem_with_indexer
return [
UserDict(
[
(random.choice(string.ascii_letters), random.randint(0, 100))
for _ in range(random.randint(0, 10))
]
)
for _ in range(100)
]

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import collections
import operator
import pytest
from pandas.compat import PY36
import pandas as pd
from pandas.tests.extension import base
import pandas.util.testing as tm
from .array import JSONArray, JSONDtype, make_data
@pytest.fixture
def dtype():
return JSONDtype()
@pytest.fixture
def data():
"""Length-100 PeriodArray for semantics test."""
data = make_data()
# Why the while loop? NumPy is unable to construct an ndarray from
# equal-length ndarrays. Many of our operations involve coercing the
# EA to an ndarray of objects. To avoid random test failures, we ensure
# that our data is coercible to an ndarray. Several tests deal with only
# the first two elements, so that's what we'll check.
while len(data[0]) == len(data[1]):
data = make_data()
return JSONArray(data)
@pytest.fixture
def data_missing():
"""Length 2 array with [NA, Valid]"""
return JSONArray([{}, {"a": 10}])
@pytest.fixture
def data_for_sorting():
return JSONArray([{"b": 1}, {"c": 4}, {"a": 2, "c": 3}])
@pytest.fixture
def data_missing_for_sorting():
return JSONArray([{"b": 1}, {}, {"a": 4}])
@pytest.fixture
def na_value(dtype):
return dtype.na_value
@pytest.fixture
def na_cmp():
return operator.eq
@pytest.fixture
def data_for_grouping():
return JSONArray(
[
{"b": 1},
{"b": 1},
{},
{},
{"a": 0, "c": 2},
{"a": 0, "c": 2},
{"b": 1},
{"c": 2},
]
)
class BaseJSON:
# NumPy doesn't handle an array of equal-length UserDicts.
# The default assert_series_equal eventually does a
# Series.values, which raises. We work around it by
# converting the UserDicts to dicts.
def assert_series_equal(self, left, right, **kwargs):
if left.dtype.name == "json":
assert left.dtype == right.dtype
left = pd.Series(
JSONArray(left.values.astype(object)), index=left.index, name=left.name
)
right = pd.Series(
JSONArray(right.values.astype(object)),
index=right.index,
name=right.name,
)
tm.assert_series_equal(left, right, **kwargs)
def assert_frame_equal(self, left, right, *args, **kwargs):
tm.assert_index_equal(
left.columns,
right.columns,
exact=kwargs.get("check_column_type", "equiv"),
check_names=kwargs.get("check_names", True),
check_exact=kwargs.get("check_exact", False),
check_categorical=kwargs.get("check_categorical", True),
obj="{obj}.columns".format(obj=kwargs.get("obj", "DataFrame")),
)
jsons = (left.dtypes == "json").index
for col in jsons:
self.assert_series_equal(left[col], right[col], *args, **kwargs)
left = left.drop(columns=jsons)
right = right.drop(columns=jsons)
tm.assert_frame_equal(left, right, *args, **kwargs)
class TestDtype(BaseJSON, base.BaseDtypeTests):
pass
class TestInterface(BaseJSON, base.BaseInterfaceTests):
def test_custom_asserts(self):
# This would always trigger the KeyError from trying to put
# an array of equal-length UserDicts inside an ndarray.
data = JSONArray(
[
collections.UserDict({"a": 1}),
collections.UserDict({"b": 2}),
collections.UserDict({"c": 3}),
]
)
a = pd.Series(data)
self.assert_series_equal(a, a)
self.assert_frame_equal(a.to_frame(), a.to_frame())
b = pd.Series(data.take([0, 0, 1]))
with pytest.raises(AssertionError):
self.assert_series_equal(a, b)
with pytest.raises(AssertionError):
self.assert_frame_equal(a.to_frame(), b.to_frame())
class TestConstructors(BaseJSON, base.BaseConstructorsTests):
@pytest.mark.skip(reason="not implemented constructor from dtype")
def test_from_dtype(self, data):
# construct from our dtype & string dtype
pass
class TestReshaping(BaseJSON, base.BaseReshapingTests):
@pytest.mark.skip(reason="Different definitions of NA")
def test_stack(self):
"""
The test does .astype(object).stack(). If we happen to have
any missing values in `data`, then we'll end up with different
rows since we consider `{}` NA, but `.astype(object)` doesn't.
"""
@pytest.mark.xfail(reason="dict for NA")
def test_unstack(self, data, index):
# The base test has NaN for the expected NA value.
# this matches otherwise
return super().test_unstack(data, index)
class TestGetitem(BaseJSON, base.BaseGetitemTests):
pass
class TestMissing(BaseJSON, base.BaseMissingTests):
@pytest.mark.skip(reason="Setting a dict as a scalar")
def test_fillna_series(self):
"""We treat dictionaries as a mapping in fillna, not a scalar."""
@pytest.mark.skip(reason="Setting a dict as a scalar")
def test_fillna_frame(self):
"""We treat dictionaries as a mapping in fillna, not a scalar."""
unhashable = pytest.mark.skip(reason="Unhashable")
unstable = pytest.mark.skipif(
not PY36, reason="Dictionary order unstable" # 3.6 or higher
)
class TestReduce(base.BaseNoReduceTests):
pass
class TestMethods(BaseJSON, base.BaseMethodsTests):
@unhashable
def test_value_counts(self, all_data, dropna):
pass
@unhashable
def test_sort_values_frame(self):
# TODO (EA.factorize): see if _values_for_factorize allows this.
pass
@unstable
def test_argsort(self, data_for_sorting):
super().test_argsort(data_for_sorting)
@unstable
def test_argsort_missing(self, data_missing_for_sorting):
super().test_argsort_missing(data_missing_for_sorting)
@unstable
@pytest.mark.parametrize("ascending", [True, False])
def test_sort_values(self, data_for_sorting, ascending):
super().test_sort_values(data_for_sorting, ascending)
@unstable
@pytest.mark.parametrize("ascending", [True, False])
def test_sort_values_missing(self, data_missing_for_sorting, ascending):
super().test_sort_values_missing(data_missing_for_sorting, ascending)
@pytest.mark.skip(reason="combine for JSONArray not supported")
def test_combine_le(self, data_repeated):
pass
@pytest.mark.skip(reason="combine for JSONArray not supported")
def test_combine_add(self, data_repeated):
pass
@pytest.mark.skip(reason="combine for JSONArray not supported")
def test_combine_first(self, data):
pass
@unhashable
def test_hash_pandas_object_works(self, data, kind):
super().test_hash_pandas_object_works(data, kind)
@pytest.mark.skip(reason="broadcasting error")
def test_where_series(self, data, na_value):
# Fails with
# *** ValueError: operands could not be broadcast together
# with shapes (4,) (4,) (0,)
super().test_where_series(data, na_value)
@pytest.mark.skip(reason="Can't compare dicts.")
def test_searchsorted(self, data_for_sorting):
super().test_searchsorted(data_for_sorting)
class TestCasting(BaseJSON, base.BaseCastingTests):
@pytest.mark.skip(reason="failing on np.array(self, dtype=str)")
def test_astype_str(self):
"""This currently fails in NumPy on np.array(self, dtype=str) with
*** ValueError: setting an array element with a sequence
"""
# We intentionally don't run base.BaseSetitemTests because pandas'
# internals has trouble setting sequences of values into scalar positions.
class TestGroupby(BaseJSON, base.BaseGroupbyTests):
@unhashable
def test_groupby_extension_transform(self):
"""
This currently fails in Series.name.setter, since the
name must be hashable, but the value is a dictionary.
I think this is what we want, i.e. `.name` should be the original
values, and not the values for factorization.
"""
@unhashable
def test_groupby_extension_apply(self):
"""
This fails in Index._do_unique_check with
> hash(val)
E TypeError: unhashable type: 'UserDict' with
I suspect that once we support Index[ExtensionArray],
we'll be able to dispatch unique.
"""
@unstable
@pytest.mark.parametrize("as_index", [True, False])
def test_groupby_extension_agg(self, as_index, data_for_grouping):
super().test_groupby_extension_agg(as_index, data_for_grouping)
class TestArithmeticOps(BaseJSON, base.BaseArithmeticOpsTests):
def test_error(self, data, all_arithmetic_operators):
pass
def test_add_series_with_extension_array(self, data):
ser = pd.Series(data)
with pytest.raises(TypeError, match="unsupported"):
ser + data
def test_divmod_series_array(self):
# GH 23287
# skipping because it is not implemented
pass
def _check_divmod_op(self, s, op, other, exc=NotImplementedError):
return super()._check_divmod_op(s, op, other, exc=TypeError)
class TestComparisonOps(BaseJSON, base.BaseComparisonOpsTests):
pass
class TestPrinting(BaseJSON, base.BasePrintingTests):
pass