venv/lib/python3.10/site-packages/pandas/tests/series/test_unary.py

import pytest

from pandas import Series
import pandas._testing as tm


class TestSeriesUnaryOps:
    # __neg__, __pos__, __invert__

    def test_neg(self):
        ser = Series(range(5), dtype="float64", name="series")
        tm.assert_series_equal(-ser, -1 * ser)

    def test_invert(self):
        ser = Series(range(5), dtype="float64", name="series")
        tm.assert_series_equal(-(ser < 0), ~(ser < 0))

    @pytest.mark.parametrize(
        "source, neg_target, abs_target",
        [
            ([1, 2, 3], [-1, -2, -3], [1, 2, 3]),
            ([1, 2, None], [-1, -2, None], [1, 2, None]),
        ],
    )
    def test_all_numeric_unary_operators(
        self, any_numeric_ea_dtype, source, neg_target, abs_target
    ):
        # GH38794
        dtype = any_numeric_ea_dtype
        ser = Series(source, dtype=dtype)
        neg_result, pos_result, abs_result = -ser, +ser, abs(ser)
        if dtype.startswith("U"):
            neg_target = -Series(source, dtype=dtype)
        else:
            neg_target = Series(neg_target, dtype=dtype)

        abs_target = Series(abs_target, dtype=dtype)

        tm.assert_series_equal(neg_result, neg_target)
        tm.assert_series_equal(pos_result, ser)
        tm.assert_series_equal(abs_result, abs_target)

    @pytest.mark.parametrize("op", ["__neg__", "__abs__"])
    def test_unary_float_op_mask(self, float_ea_dtype, op):
        dtype = float_ea_dtype
        ser = Series([1.1, 2.2, 3.3], dtype=dtype)
        result = getattr(ser, op)()
        target = result.copy(deep=True)
        ser[0] = None
        tm.assert_series_equal(result, target)