Inzynierka/Lib/site-packages/pandas/tests/interchange/test_utils.py
2023-06-02 12:51:02 +02:00

41 lines
1.3 KiB
Python

import numpy as np
import pytest
import pandas as pd
from pandas.core.interchange.utils import dtype_to_arrow_c_fmt
# TODO: use ArrowSchema to get reference C-string.
# At the time, there is no way to access ArrowSchema holding a type format string
# from python. The only way to access it is to export the structure to a C-pointer,
# see DataType._export_to_c() method defined in
# https://github.com/apache/arrow/blob/master/python/pyarrow/types.pxi
@pytest.mark.parametrize(
"pandas_dtype, c_string",
[
(np.dtype("bool"), "b"),
(np.dtype("int8"), "c"),
(np.dtype("uint8"), "C"),
(np.dtype("int16"), "s"),
(np.dtype("uint16"), "S"),
(np.dtype("int32"), "i"),
(np.dtype("uint32"), "I"),
(np.dtype("int64"), "l"),
(np.dtype("uint64"), "L"),
(np.dtype("float16"), "e"),
(np.dtype("float32"), "f"),
(np.dtype("float64"), "g"),
(pd.Series(["a"]).dtype, "u"),
(
pd.Series([0]).astype("datetime64[ns]").dtype,
"tsn:",
),
(pd.CategoricalDtype(["a"]), "l"),
(np.dtype("O"), "u"),
],
)
def test_dtype_to_arrow_c_fmt(pandas_dtype, c_string): # PR01
"""Test ``dtype_to_arrow_c_fmt`` utility function."""
assert dtype_to_arrow_c_fmt(pandas_dtype) == c_string