python-by-example-150-chall.../venv/lib/python3.6/site-packages/pandas/tests/arrays/test_datetimes.py
2019-08-04 15:26:35 +03:00

315 lines
11 KiB
Python

"""
Tests for DatetimeArray
"""
import operator
import numpy as np
import pytest
from pandas.core.dtypes.dtypes import DatetimeTZDtype
import pandas as pd
from pandas.core.arrays import DatetimeArray
from pandas.core.arrays.datetimes import sequence_to_dt64ns
import pandas.util.testing as tm
class TestDatetimeArrayConstructor:
def test_only_1dim_accepted(self):
arr = np.array([0, 1, 2, 3], dtype="M8[h]").astype("M8[ns]")
with pytest.raises(ValueError, match="Only 1-dimensional"):
# 2-dim
DatetimeArray(arr.reshape(2, 2))
with pytest.raises(ValueError, match="Only 1-dimensional"):
# 0-dim
DatetimeArray(arr[[0]].squeeze())
def test_freq_validation(self):
# GH#24623 check that invalid instances cannot be created with the
# public constructor
arr = np.arange(5, dtype=np.int64) * 3600 * 10 ** 9
msg = (
"Inferred frequency H from passed values does not "
"conform to passed frequency W-SUN"
)
with pytest.raises(ValueError, match=msg):
DatetimeArray(arr, freq="W")
@pytest.mark.parametrize(
"meth",
[
DatetimeArray._from_sequence,
sequence_to_dt64ns,
pd.to_datetime,
pd.DatetimeIndex,
],
)
def test_mixing_naive_tzaware_raises(self, meth):
# GH#24569
arr = np.array([pd.Timestamp("2000"), pd.Timestamp("2000", tz="CET")])
msg = (
"Cannot mix tz-aware with tz-naive values|"
"Tz-aware datetime.datetime cannot be converted "
"to datetime64 unless utc=True"
)
for obj in [arr, arr[::-1]]:
# check that we raise regardless of whether naive is found
# before aware or vice-versa
with pytest.raises(ValueError, match=msg):
meth(obj)
def test_from_pandas_array(self):
arr = pd.array(np.arange(5, dtype=np.int64)) * 3600 * 10 ** 9
result = DatetimeArray._from_sequence(arr, freq="infer")
expected = pd.date_range("1970-01-01", periods=5, freq="H")._data
tm.assert_datetime_array_equal(result, expected)
def test_mismatched_timezone_raises(self):
arr = DatetimeArray(
np.array(["2000-01-01T06:00:00"], dtype="M8[ns]"),
dtype=DatetimeTZDtype(tz="US/Central"),
)
dtype = DatetimeTZDtype(tz="US/Eastern")
with pytest.raises(TypeError, match="Timezone of the array"):
DatetimeArray(arr, dtype=dtype)
def test_non_array_raises(self):
with pytest.raises(ValueError, match="list"):
DatetimeArray([1, 2, 3])
def test_other_type_raises(self):
with pytest.raises(
ValueError, match="The dtype of 'values' is incorrect.*bool"
):
DatetimeArray(np.array([1, 2, 3], dtype="bool"))
def test_incorrect_dtype_raises(self):
with pytest.raises(ValueError, match="Unexpected value for 'dtype'."):
DatetimeArray(np.array([1, 2, 3], dtype="i8"), dtype="category")
def test_freq_infer_raises(self):
with pytest.raises(ValueError, match="Frequency inference"):
DatetimeArray(np.array([1, 2, 3], dtype="i8"), freq="infer")
def test_copy(self):
data = np.array([1, 2, 3], dtype="M8[ns]")
arr = DatetimeArray(data, copy=False)
assert arr._data is data
arr = DatetimeArray(data, copy=True)
assert arr._data is not data
class TestDatetimeArrayComparisons:
# TODO: merge this into tests/arithmetic/test_datetime64 once it is
# sufficiently robust
def test_cmp_dt64_arraylike_tznaive(self, all_compare_operators):
# arbitrary tz-naive DatetimeIndex
opname = all_compare_operators.strip("_")
op = getattr(operator, opname)
dti = pd.date_range("2016-01-1", freq="MS", periods=9, tz=None)
arr = DatetimeArray(dti)
assert arr.freq == dti.freq
assert arr.tz == dti.tz
right = dti
expected = np.ones(len(arr), dtype=bool)
if opname in ["ne", "gt", "lt"]:
# for these the comparisons should be all-False
expected = ~expected
result = op(arr, arr)
tm.assert_numpy_array_equal(result, expected)
for other in [right, np.array(right)]:
# TODO: add list and tuple, and object-dtype once those
# are fixed in the constructor
result = op(arr, other)
tm.assert_numpy_array_equal(result, expected)
result = op(other, arr)
tm.assert_numpy_array_equal(result, expected)
class TestDatetimeArray:
def test_astype_to_same(self):
arr = DatetimeArray._from_sequence(["2000"], tz="US/Central")
result = arr.astype(DatetimeTZDtype(tz="US/Central"), copy=False)
assert result is arr
@pytest.mark.parametrize("dtype", [int, np.int32, np.int64, "uint32", "uint64"])
def test_astype_int(self, dtype):
arr = DatetimeArray._from_sequence([pd.Timestamp("2000"), pd.Timestamp("2001")])
result = arr.astype(dtype)
if np.dtype(dtype).kind == "u":
expected_dtype = np.dtype("uint64")
else:
expected_dtype = np.dtype("int64")
expected = arr.astype(expected_dtype)
assert result.dtype == expected_dtype
tm.assert_numpy_array_equal(result, expected)
def test_tz_setter_raises(self):
arr = DatetimeArray._from_sequence(["2000"], tz="US/Central")
with pytest.raises(AttributeError, match="tz_localize"):
arr.tz = "UTC"
def test_setitem_different_tz_raises(self):
data = np.array([1, 2, 3], dtype="M8[ns]")
arr = DatetimeArray(data, copy=False, dtype=DatetimeTZDtype(tz="US/Central"))
with pytest.raises(ValueError, match="None"):
arr[0] = pd.Timestamp("2000")
with pytest.raises(ValueError, match="US/Central"):
arr[0] = pd.Timestamp("2000", tz="US/Eastern")
def test_setitem_clears_freq(self):
a = DatetimeArray(pd.date_range("2000", periods=2, freq="D", tz="US/Central"))
a[0] = pd.Timestamp("2000", tz="US/Central")
assert a.freq is None
def test_repeat_preserves_tz(self):
dti = pd.date_range("2000", periods=2, freq="D", tz="US/Central")
arr = DatetimeArray(dti)
repeated = arr.repeat([1, 1])
# preserves tz and values, but not freq
expected = DatetimeArray(arr.asi8, freq=None, dtype=arr.dtype)
tm.assert_equal(repeated, expected)
def test_value_counts_preserves_tz(self):
dti = pd.date_range("2000", periods=2, freq="D", tz="US/Central")
arr = DatetimeArray(dti).repeat([4, 3])
result = arr.value_counts()
# Note: not tm.assert_index_equal, since `freq`s do not match
assert result.index.equals(dti)
arr[-2] = pd.NaT
result = arr.value_counts()
expected = pd.Series([1, 4, 2], index=[pd.NaT, dti[0], dti[1]])
tm.assert_series_equal(result, expected)
@pytest.mark.parametrize("method", ["pad", "backfill"])
def test_fillna_preserves_tz(self, method):
dti = pd.date_range("2000-01-01", periods=5, freq="D", tz="US/Central")
arr = DatetimeArray(dti, copy=True)
arr[2] = pd.NaT
fill_val = dti[1] if method == "pad" else dti[3]
expected = DatetimeArray._from_sequence(
[dti[0], dti[1], fill_val, dti[3], dti[4]], freq=None, tz="US/Central"
)
result = arr.fillna(method=method)
tm.assert_extension_array_equal(result, expected)
# assert that arr and dti were not modified in-place
assert arr[2] is pd.NaT
assert dti[2] == pd.Timestamp("2000-01-03", tz="US/Central")
def test_array_interface_tz(self):
tz = "US/Central"
data = DatetimeArray(pd.date_range("2017", periods=2, tz=tz))
result = np.asarray(data)
expected = np.array(
[
pd.Timestamp("2017-01-01T00:00:00", tz=tz),
pd.Timestamp("2017-01-02T00:00:00", tz=tz),
],
dtype=object,
)
tm.assert_numpy_array_equal(result, expected)
result = np.asarray(data, dtype=object)
tm.assert_numpy_array_equal(result, expected)
result = np.asarray(data, dtype="M8[ns]")
expected = np.array(
["2017-01-01T06:00:00", "2017-01-02T06:00:00"], dtype="M8[ns]"
)
tm.assert_numpy_array_equal(result, expected)
def test_array_interface(self):
data = DatetimeArray(pd.date_range("2017", periods=2))
expected = np.array(
["2017-01-01T00:00:00", "2017-01-02T00:00:00"], dtype="datetime64[ns]"
)
result = np.asarray(data)
tm.assert_numpy_array_equal(result, expected)
result = np.asarray(data, dtype=object)
expected = np.array(
[pd.Timestamp("2017-01-01T00:00:00"), pd.Timestamp("2017-01-02T00:00:00")],
dtype=object,
)
tm.assert_numpy_array_equal(result, expected)
class TestSequenceToDT64NS:
def test_tz_dtype_mismatch_raises(self):
arr = DatetimeArray._from_sequence(["2000"], tz="US/Central")
with pytest.raises(TypeError, match="data is already tz-aware"):
sequence_to_dt64ns(arr, dtype=DatetimeTZDtype(tz="UTC"))
def test_tz_dtype_matches(self):
arr = DatetimeArray._from_sequence(["2000"], tz="US/Central")
result, _, _ = sequence_to_dt64ns(arr, dtype=DatetimeTZDtype(tz="US/Central"))
tm.assert_numpy_array_equal(arr._data, result)
class TestReductions:
@pytest.mark.parametrize("tz", [None, "US/Central"])
def test_min_max(self, tz):
arr = DatetimeArray._from_sequence(
[
"2000-01-03",
"2000-01-03",
"NaT",
"2000-01-02",
"2000-01-05",
"2000-01-04",
],
tz=tz,
)
result = arr.min()
expected = pd.Timestamp("2000-01-02", tz=tz)
assert result == expected
result = arr.max()
expected = pd.Timestamp("2000-01-05", tz=tz)
assert result == expected
result = arr.min(skipna=False)
assert result is pd.NaT
result = arr.max(skipna=False)
assert result is pd.NaT
@pytest.mark.parametrize("tz", [None, "US/Central"])
@pytest.mark.parametrize("skipna", [True, False])
def test_min_max_empty(self, skipna, tz):
arr = DatetimeArray._from_sequence([], tz=tz)
result = arr.min(skipna=skipna)
assert result is pd.NaT
result = arr.max(skipna=skipna)
assert result is pd.NaT