ai-content-maker/.venv/Lib/site-packages/pandas/tests/series/methods/test_copy.py

91 lines
2.9 KiB
Python

import numpy as np
import pytest
from pandas import (
Series,
Timestamp,
)
import pandas._testing as tm
class TestCopy:
@pytest.mark.parametrize("deep", ["default", None, False, True])
def test_copy(self, deep, using_copy_on_write):
ser = Series(np.arange(10), dtype="float64")
# default deep is True
if deep == "default":
ser2 = ser.copy()
else:
ser2 = ser.copy(deep=deep)
if using_copy_on_write:
# INFO(CoW) a shallow copy doesn't yet copy the data
# but parent will not be modified (CoW)
if deep is None or deep is False:
assert np.may_share_memory(ser.values, ser2.values)
else:
assert not np.may_share_memory(ser.values, ser2.values)
ser2[::2] = np.NaN
if deep is not False or using_copy_on_write:
# Did not modify original Series
assert np.isnan(ser2[0])
assert not np.isnan(ser[0])
else:
# we DID modify the original Series
assert np.isnan(ser2[0])
assert np.isnan(ser[0])
@pytest.mark.parametrize("deep", ["default", None, False, True])
def test_copy_tzaware(self, deep, using_copy_on_write):
# GH#11794
# copy of tz-aware
expected = Series([Timestamp("2012/01/01", tz="UTC")])
expected2 = Series([Timestamp("1999/01/01", tz="UTC")])
ser = Series([Timestamp("2012/01/01", tz="UTC")])
if deep == "default":
ser2 = ser.copy()
else:
ser2 = ser.copy(deep=deep)
if using_copy_on_write:
# INFO(CoW) a shallow copy doesn't yet copy the data
# but parent will not be modified (CoW)
if deep is None or deep is False:
assert np.may_share_memory(ser.values, ser2.values)
else:
assert not np.may_share_memory(ser.values, ser2.values)
ser2[0] = Timestamp("1999/01/01", tz="UTC")
# default deep is True
if deep is not False or using_copy_on_write:
# Did not modify original Series
tm.assert_series_equal(ser2, expected2)
tm.assert_series_equal(ser, expected)
else:
# we DID modify the original Series
tm.assert_series_equal(ser2, expected2)
tm.assert_series_equal(ser, expected2)
def test_copy_name(self, datetime_series):
result = datetime_series.copy()
assert result.name == datetime_series.name
def test_copy_index_name_checking(self, datetime_series):
# don't want to be able to modify the index stored elsewhere after
# making a copy
datetime_series.index.name = None
assert datetime_series.index.name is None
assert datetime_series is datetime_series
cp = datetime_series.copy()
cp.index.name = "foo"
assert datetime_series.index.name is None