projektAI/venv/Lib/site-packages/pandas/tests/extension/base/casting.py
2021-06-06 22:13:05 +02:00

68 lines
2.2 KiB
Python

import numpy as np
import pytest
import pandas as pd
from pandas.core.internals import ObjectBlock
from .base import BaseExtensionTests
class BaseCastingTests(BaseExtensionTests):
"""Casting to and from ExtensionDtypes"""
def test_astype_object_series(self, all_data):
ser = pd.Series(all_data, name="A")
result = ser.astype(object)
assert isinstance(result._mgr.blocks[0], ObjectBlock)
def test_astype_object_frame(self, all_data):
df = pd.DataFrame({"A": all_data})
result = df.astype(object)
blk = result._data.blocks[0]
assert isinstance(blk, ObjectBlock), type(blk)
# FIXME: these currently fail; dont leave commented-out
# check that we can compare the dtypes
# cmp = result.dtypes.equals(df.dtypes)
# assert not cmp.any()
def test_tolist(self, data):
result = pd.Series(data).tolist()
expected = list(data)
assert result == expected
def test_astype_str(self, data):
result = pd.Series(data[:5]).astype(str)
expected = pd.Series([str(x) for x in data[:5]], dtype=str)
self.assert_series_equal(result, expected)
def test_astype_string(self, data):
# GH-33465
result = pd.Series(data[:5]).astype("string")
expected = pd.Series([str(x) for x in data[:5]], dtype="string")
self.assert_series_equal(result, expected)
def test_to_numpy(self, data):
expected = np.asarray(data)
result = data.to_numpy()
self.assert_equal(result, expected)
result = pd.Series(data).to_numpy()
self.assert_equal(result, expected)
def test_astype_empty_dataframe(self, dtype):
# https://github.com/pandas-dev/pandas/issues/33113
df = pd.DataFrame()
result = df.astype(dtype)
self.assert_frame_equal(result, df)
@pytest.mark.parametrize("copy", [True, False])
def test_astype_own_type(self, data, copy):
# ensure that astype returns the original object for equal dtype and copy=False
# https://github.com/pandas-dev/pandas/issues/28488
result = data.astype(data.dtype, copy=copy)
assert (result is data) is (not copy)
self.assert_extension_array_equal(result, data)