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pandas / tests / scalar / timedelta / test_timedelta.py
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""" test the scalar Timedelta """
from datetime import timedelta

import numpy as np
import pytest

from pandas._libs.tslibs import NaT, Timestamp, iNaT

import pandas as pd
from pandas import Series, Timedelta, TimedeltaIndex, timedelta_range, to_timedelta
import pandas._testing as tm


class TestTimedeltaArithmetic:
    def test_arithmetic_overflow(self):
        with pytest.raises(OverflowError):
            Timestamp("1700-01-01") + Timedelta(13 * 19999, unit="D")

        with pytest.raises(OverflowError):
            Timestamp("1700-01-01") + timedelta(days=13 * 19999)

    def test_array_timedelta_floordiv(self):
        # deprecated GH#19761, enforced GH#29797
        ints = pd.date_range("2012-10-08", periods=4, freq="D").view("i8")

        with pytest.raises(TypeError, match="Invalid dtype"):
            ints // Timedelta(1, unit="s")

    def test_ops_error_str(self):
        # GH 13624
        td = Timedelta("1 day")

        for left, right in [(td, "a"), ("a", td)]:

            with pytest.raises(TypeError):
                left + right

            with pytest.raises(TypeError):
                left > right

            assert not left == right
            assert left != right

    def test_ops_notimplemented(self):
        class Other:
            pass

        other = Other()

        td = Timedelta("1 day")
        assert td.__add__(other) is NotImplemented
        assert td.__sub__(other) is NotImplemented
        assert td.__truediv__(other) is NotImplemented
        assert td.__mul__(other) is NotImplemented
        assert td.__floordiv__(other) is NotImplemented

    def test_unary_ops(self):
        td = Timedelta(10, unit="d")

        # __neg__, __pos__
        assert -td == Timedelta(-10, unit="d")
        assert -td == Timedelta("-10d")
        assert +td == Timedelta(10, unit="d")

        # __abs__, __abs__(__neg__)
        assert abs(td) == td
        assert abs(-td) == td
        assert abs(-td) == Timedelta("10d")


class TestTimedeltaComparison:
    def test_compare_tick(self, tick_classes):
        cls = tick_classes

        off = cls(4)
        td = off.delta
        assert isinstance(td, Timedelta)

        assert td == off
        assert not td != off
        assert td <= off
        assert td >= off
        assert not td < off
        assert not td > off

        assert not td == 2 * off
        assert td != 2 * off
        assert td <= 2 * off
        assert td < 2 * off
        assert not td >= 2 * off
        assert not td > 2 * off

    def test_comparison_object_array(self):
        # analogous to GH#15183
        td = Timedelta("2 days")
        other = Timedelta("3 hours")

        arr = np.array([other, td], dtype=object)
        res = arr == td
        expected = np.array([False, True], dtype=bool)
        assert (res == expected).all()

        # 2D case
        arr = np.array([[other, td], [td, other]], dtype=object)
        res = arr != td
        expected = np.array([[True, False], [False, True]], dtype=bool)
        assert res.shape == expected.shape
        assert (res == expected).all()

    def test_compare_timedelta_ndarray(self):
        # GH11835
        periods = [Timedelta("0 days 01:00:00"), Timedelta("0 days 01:00:00")]
        arr = np.array(periods)
        result = arr[0] > arr
        expected = np.array([False, False])
        tm.assert_numpy_array_equal(result, expected)

    @pytest.mark.skip(reason="GH#20829 is reverted until after 0.24.0")
    def test_compare_custom_object(self):
        """
        Make sure non supported operations on Timedelta returns NonImplemented
        and yields to other operand (GH#20829).
        """

        class CustomClass:
            def __init__(self, cmp_result=None):
                self.cmp_result = cmp_result

            def generic_result(self):
                if self.cmp_result is None:
                    return NotImplemented
                else:
                    return self.cmp_result

            def __eq__(self, other):
                return self.generic_result()

            def __gt__(self, other):
                return self.generic_result()

        t = Timedelta("1s")

        assert not (t == "string")
        assert not (t == 1)
        assert not (t == CustomClass())
        assert not (t == CustomClass(cmp_result=False))

        assert t < CustomClass(cmp_result=True)
        assert not (t < CustomClass(cmp_result=False))

        assert t == CustomClass(cmp_result=True)

    @pytest.mark.parametrize("val", ["string", 1])
    def test_compare_unknown_type(self, val):
        # GH20829
        t = Timedelta("1s")
        with pytest.raises(TypeError):
            t >= val
        with pytest.raises(TypeError):
            t > val
        with pytest.raises(TypeError):
            t <= val
        with pytest.raises(TypeError):
            t < val


class TestTimedeltas:
    @pytest.mark.parametrize(
        "unit, value, expected",
        [
            ("us", 9.999, 9999),
            ("ms", 9.999999, 9999999),
            ("s", 9.999999999, 9999999999),
        ],
    )
    def test_rounding_on_int_unit_construction(self, unit, value, expected):
        # GH 12690
        result = Timedelta(value, unit=unit)
        assert result.value == expected
        result = Timedelta(str(value) + unit)
        assert result.value == expected

    def test_total_seconds_scalar(self):
        # see gh-10939
        rng = Timedelta("1 days, 10:11:12.100123456")
        expt = 1 * 86400 + 10 * 3600 + 11 * 60 + 12 + 100123456.0 / 1e9
        tm.assert_almost_equal(rng.total_seconds(), expt)

        rng = Timedelta(np.nan)
        assert np.isnan(rng.total_seconds())

    def test_conversion(self):

        for td in [Timedelta(10, unit="d"), Timedelta("1 days, 10:11:12.012345")]:
            pydt = td.to_pytimedelta()
            assert td == Timedelta(pydt)
            assert td == pydt
            assert isinstance(pydt, timedelta) and not isinstance(pydt, Timedelta)

            assert td == np.timedelta64(td.value, "ns")
            td64 = td.to_timedelta64()

            assert td64 == np.timedelta64(td.value, "ns")
            assert td == td64

            assert isinstance(td64, np.timedelta64)

        # this is NOT equal and cannot be roundtripped (because of the nanos)
        td = Timedelta("1 days, 10:11:12.012345678")
        assert td != td.to_pytimedelta()

    def test_freq_conversion(self):

        # truediv
        td = Timedelta("1 days 2 hours 3 ns")
        result = td / np.timedelta64(1, "D")
        assert result == td.value / float(86400 * 1e9)
        result = td / np.timedelta64(1, "s")
        assert result == td.value / float(1e9)
        result = td / np.timedelta64(1, "ns")
        assert result == td.value

        # floordiv
        td = Timedelta("1 days 2 hours 3 ns")
        result = td // np.timedelta64(1, "D")
        assert result == 1
        result = td // np.timedelta64(1, "s")
        assert result == 93600
        result = td // np.timedelta64(1, "ns")
        assert result == td.value

    def test_fields(self):
        def check(value):
            # that we are int
            assert isinstance(value, int)

        # compat to datetime.timedelta
        rng = to_timedelta("1 days, 10:11:12")
        assert rng.days == 1
        assert rng.seconds == 10 * 3600 + 11 * 60 + 12
        assert rng.microseconds == 0
        assert rng.nanoseconds == 0

        msg = "'Timedelta' object has no attribute '{}'"
        with pytest.raises(AttributeError, match=msg.format("hours")):
            rng.hours
        with pytest.raises(AttributeError, match=msg.format("minutes")):
            rng.minutes
        with pytest.raises(AttributeError, match=msg.format("milliseconds")):
            rng.milliseconds

        # GH 10050
        check(rng.days)
        check(rng.seconds)
        check(rng.microseconds)
        check(rng.nanoseconds)

        td = Timedelta("-1 days, 10:11:12")
        assert abs(td) == Timedelta("13:48:48")
        assert str(td) == "-1 days +10:11:12"
        assert -td == Timedelta("0 days 13:48:48")
        assert -Timedelta("-1 days, 10:11:12").value == 49728000000000
        assert Timedelta("-1 days, 10:11:12").value == -49728000000000

        rng = to_timedelta("-1 days, 10:11:12.100123456")
        assert rng.days == -1
        assert rng.seconds == 10 * 3600 + 11 * 60 + 12
        assert rng.microseconds == 100 * 1000 + 123
        assert rng.nanoseconds == 456
        msg = "'Timedelta' object has no attribute '{}'"
        with pytest.raises(AttributeError, match=msg.format("hours")):
            rng.hours
        with pytest.raises(AttributeError, match=msg.format("minutes")):
            rng.minutes
        with pytest.raises(AttributeError, match=msg.format("milliseconds")):
            rng.milliseconds

        # components
        tup = to_timedelta(-1, "us").components
        assert tup.days == -1
        assert tup.hours == 23
        assert tup.minutes == 59
        assert tup.seconds == 59
        assert tup.milliseconds == 999
        assert tup.microseconds == 999
        assert tup.nanoseconds == 0

        # GH 10050
        check(tup.days)
        check(tup.hours)
        check(tup.minutes)
        check(tup.seconds)
        check(tup.milliseconds)
        check(tup.microseconds)
        check(tup.nanoseconds)

        tup = Timedelta("-1 days 1 us").components
        assert tup.days == -2
        assert tup.hours == 23
        assert tup.minutes == 59
        assert tup.seconds == 59
        assert tup.milliseconds == 999
        assert tup.microseconds == 999
        assert tup.nanoseconds == 0

    def test_iso_conversion(self):
        # GH #21877
        expected = Timedelta(1, unit="s")
        assert to_timedelta("P0DT0H0M1S") == expected

    def test_nat_converters(self):
        result = to_timedelta("nat").to_numpy()
        assert result.dtype.kind == "M"
        assert result.astype("int64") == iNaT

        result = to_timedelta("nan").to_numpy()
        assert result.dtype.kind == "M"
        assert result.astype("int64") == iNaT

    @pytest.mark.parametrize(
        "units, np_unit",
        [
            (["W", "w"], "W"),
            (["D", "d", "days", "day", "Days", "Day"], "D"),
            (
                ["m", "minute", "min", "minutes", "t", "Minute", "Min", "Minutes", "T"],
                "m",
            ),
            (["s", "seconds", "sec", "second", "S", "Seconds", "Sec", "Second"], "s"),
            (
                [
                    "ms",
                    "milliseconds",
                    "millisecond",
                    "milli",
                    "millis",
                    "l",
                    "MS",
                    "Milliseconds",
                    "Millisecond",
                    "Milli",
                    "Millis",
                    "L",
                ],
                "ms",
            ),
            (
                [
                    "us",
                    "microseconds",
                    "microsecond",
                    "micro",
                    "micros",
                    "u",
                    "US",
                    "Microseconds",
                    "Microsecond",
                    "Micro",
                    "Micros",
                    "U",
                ],
                "us",
            ),
            (
                [
                    "ns",
                    "nanoseconds",
                    "nanosecond",
                    "nano",
                    "nanos",
                    "n",
                    "NS",
                    "Nanoseconds",
                    "Nanosecond",
                    "Nano",
                    "Nanos",
                    "N",
                ],
                "ns",
            ),
        ],
    )
    @pytest.mark.parametrize("wrapper", [np.array, list, pd.Index])
    def test_unit_parser(self, units, np_unit, wrapper):
        # validate all units, GH 6855, GH 21762
        for unit in units:
            # array-likes
            expected = TimedeltaIndex(
                [np.timedelta64(i, np_unit) for i in np.arange(5).tolist()]
            )
            result = to_timedelta(wrapper(range(5)), unit=unit)
            tm.assert_index_equal(result, expected)
            result = TimedeltaIndex(wrapper(range(5)), unit=unit)
            tm.assert_index_equal(result, expected)

            if unit == "M":
                # M is treated as minutes in string repr
                expected = TimedeltaIndex(
                    [np.timedelta64(i, "m") for i in np.arange(5).tolist()]
                )

            str_repr = [f"{x}{unit}" for x in np.arange(5)]
            result = to_timedelta(wrapper(str_repr))
            tm.assert_index_equal(result, expected)
            result = TimedeltaIndex(wrapper(str_repr))
            tm.assert_index_equal(result, expected)

            # scalar
            expected = Timedelta(np.timedelta64(2, np_unit).astype("timedelta64[ns]"))

            result = to_timedelta(2, unit=unit)
            assert result == expected
            result = Timedelta(2, unit=unit)
            assert result == expected

            if unit == "M":
                expected = Timedelta(np.timedelta64(2, "m").astype("timedelta64[ns]"))

            result = to_timedelta(f"2{unit}")
            assert result == expected
            result = Timedelta(f"2{unit}")
            assert result == expected

    @pytest.mark.parametrize("unit", ["Y", "y", "M"])
    def test_unit_m_y_raises(self, unit):
        msg = "Units 'M' and 'Y' are no longer supported"
        with pytest.raises(ValueError, match=msg):
            Timedelta(10, unit)

        with pytest.raises(ValueError, match=msg):
            to_timedelta(10, unit)

        with pytest.raises(ValueError, match=msg):
            to_timedelta([1, 2], unit)

    def test_numeric_conversions(self):
        assert Timedelta(0) == np.timedelta64(0, "ns")
        assert Timedelta(10) == np.timedelta64(10, "ns")
        assert Timedelta(10, unit="ns") == np.timedelta64(10, "ns")

        assert Timedelta(10, unit="us") == np.timedelta64(10, "us")
        assert Timedelta(10, unit="ms") == np.timedelta64(10, "ms")
        assert Timedelta(10, unit="s") == np.timedelta64(10, "s")
        assert Timedelta(10, unit="d") == np.timedelta64(10, "D")

    def test_timedelta_conversions(self):
        assert Timedelta(timedelta(seconds=1)) == np.timedelta64(1, "s").astype(
            "m8[ns]"
        )
        assert Timedelta(timedelta(microseconds=1)) == np.timedelta64(1, "us").astype(
            "m8[ns]"
        )
        assert Timedelta(timedelta(days=1)) == np.timedelta64(1, "D").astype("m8[ns]")

    def test_to_numpy_alias(self):
        # GH 24653: alias .to_numpy() for scalars
        td = Timedelta("10m7s")
        assert td.to_timedelta64() == td.to_numpy()

    def test_round(self):

        t1 = Timedelta("1 days 02:34:56.789123456")
        t2 = Timedelta("-1 days 02:34:56.789123456")

        for (freq, s1, s2) in [
            ("N", t1, t2),
            (
                "U",
                Timedelta("1 days 02:34:56.789123000"),
                Timedelta("-1 days 02:34:56.789123000"),
            ),
            (
                "L",
                Timedelta("1 days 02:34:56.789000000"),
                Timedelta("-1 days 02:34:56.789000000"),
            ),
            ("S", Timedelta("1 days 02:34:57"), Timedelta("-1 days 02:34:57")),
            ("2S", Timedelta("1 days 02:34:56"), Timedelta("-1 days 02:34:56")),
            ("5S", Timedelta("1 days 02:34:55"), Timedelta("-1 days 02:34:55")),
            ("T", Timedelta("1 days 02:35:00"), Timedelta("-1 days 02:35:00")),
            ("12T", Timedelta("1 days 02:36:00"), Timedelta("-1 days 02:36:00")),
            ("H", Timedelta("1 days 03:00:00"), Timedelta("-1 days 03:00:00")),
            ("d", Timedelta("1 days"), Timedelta("-1 days")),
        ]:
            r1 = t1.round(freq)
            assert r1 == s1
            r2 = t2.round(freq)
            assert r2 == s2

        # invalid
        for freq, msg in [
            ("Y", "<YearEnd: month=12> is a non-fixed frequency"),
            ("M", "<MonthEnd> is a non-fixed frequency"),
            ("foobar", "Invalid frequency: foobar"),
        ]:
            with pytest.raises(ValueError, match=msg):
                t1.round(freq)

        t1 = timedelta_range("1 days", periods=3, freq="1 min 2 s 3 us")
        t2 = -1 * t1
        t1a = timedelta_range("1 days", periods=3, freq="1 min 2 s")
        t1c = TimedeltaIndex([1, 1, 1], unit="D")

        # note that negative times round DOWN! so don't give whole numbers
        for (freq, s1, s2) in [
            ("N", t1, t2),
            ("U", t1, t2),
            (
                "L",
                t1a,
                TimedeltaIndex(
                    ["-1 days +00:00:00", "-2 days +23:58:58", "-2 days +23:57:56"],
                    dtype="timedelta64[ns]",
                    freq=None,
                ),
            ),
            (
                "S",
                t1a,
                TimedeltaIndex(
                    ["-1 days +00:00:00", "-2 days +23:58:58", "-2 days +23:57:56"],
                    dtype="timedelta64[ns]",
                    freq=None,
                ),
            ),
            (
                "12T",
                t1c,
                TimedeltaIndex(
                    ["-1 days", "-1 days", "-1 days"],
                    dtype="timedelta64[ns]",
                    freq=None,
                ),
            ),
            (
                "H",
                t1c,
                TimedeltaIndex(
                    ["-1 days", "-1 days", "-1 days"],
                    dtype="timedelta64[ns]",
                    freq=None,
                ),
            ),
            ("d", t1c, TimedeltaIndex([-1, -1, -1], unit="D")),
        ]:

            r1 = t1.round(freq)
            tm.assert_index_equal(r1, s1)
            r2 = t2.round(freq)
            tm.assert_index_equal(r2, s2)

        # invalid
        for freq, msg in [
            ("Y", "<YearEnd: month=12> is a non-fixed frequency"),
            ("M", "<MonthEnd> is a non-fixed frequency"),
            ("foobar", "Invalid frequency: foobar"),
        ]:
            with pytest.raises(ValueError, match=msg):
                t1.round(freq)

    def test_contains(self):
        # Checking for any NaT-like objects
        # GH 13603
        td = to_timedelta(range(5), unit="d") + pd.offsets.Hour(1)
        for v in [NaT, None, float("nan"), np.nan]:
            assert not (v in td)

        td = to_timedelta([NaT])
        for v in [NaT, None, float("nan"), np.nan]:
            assert v in td

    def test_identity(self):

        td = Timedelta(10, unit="d")
        assert isinstance(td, Timedelta)
        assert isinstance(td, timedelta)

    def test_short_format_converters(self):
        def conv(v):
            return v.astype("m8[ns]")

        assert Timedelta("10") == np.timedelta64(10, "ns")
        assert Timedelta("10ns") == np.timedelta64(10, "ns")
        assert Timedelta("100") == np.timedelta64(100, "ns")
        assert Timedelta("100ns") == np.timedelta64(100, "ns")

        assert Timedelta("1000") == np.timedelta64(1000, "ns")
        assert Timedelta("1000ns") == np.timedelta64(1000, "ns")
        assert Timedelta("1000NS") == np.timedelta64(1000, "ns")

        assert Timedelta("10us") == np.timedelta64(10000, "ns")
        assert Timedelta("100us") == np.timedelta64(100000, "ns")
        assert Timedelta("1000us") == np.timedelta64(1000000, "ns")
        assert Timedelta("1000Us") == np.timedelta64(1000000, "ns")
        assert Timedelta("1000uS") == np.timedelta64(1000000, "ns")

        assert Timedelta("1ms") == np.timedelta64(1000000, "ns")
        assert Timedelta("10ms") == np.timedelta64(10000000, "ns")
        assert Timedelta("100ms") == np.timedelta64(100000000, "ns")
        assert Timedelta("1000ms") == np.timedelta64(1000000000, "ns")

        assert Timedelta("-1s") == -np.timedelta64(1000000000, "ns")
        assert Timedelta("1s") == np.timedelta64(1000000000, "ns")
        assert Timedelta("10s") == np.timedelta64(10000000000, "ns")
        assert Timedelta("100s") == np.timedelta64(100000000000, "ns")
        assert Timedelta("1000s") == np.timedelta64(1000000000000, "ns")

        assert Timedelta("1d") == conv(np.timedelta64(1, "D"))
        assert Timedelta("-1d") == -conv(np.timedelta64(1, "D"))
        assert Timedelta("1D") == conv(np.timedelta64(1, "D"))
        assert Timedelta("10D") == conv(np.timedelta64(10, "D"))
        assert Timedelta("100D") == conv(np.timedelta64(100, "D"))
        assert Timedelta("1000D") == conv(np.timedelta64(1000, "D"))
        assert Timedelta("10000D") == conv(np.timedelta64(10000, "D"))

        # space
        assert Timedelta(" 10000D ") == conv(np.timedelta64(10000, "D"))
        assert Timedelta(" - 10000D ") == -conv(np.timedelta64(10000, "D"))

        # invalid
        with pytest.raises(ValueError):
            Timedelta("1foo")
        with pytest.raises(ValueError):
            Timedelta("foo")

    def test_full_format_converters(self):
        def conv(v):
            return v.astype("m8[ns]")

        d1 = np.timedelta64(1, "D")

        assert Timedelta("1days") == conv(d1)
        assert Timedelta("1days,") == conv(d1)
        assert Timedelta("- 1days,") == -conv(d1)

        assert Timedelta("00:00:01") == conv(np.timedelta64(1, "s"))
        assert Timedelta("06:00:01") == conv(np.timedelta64(6 * 3600 + 1, "s"))
        assert Timedelta("06:00:01.0") == conv(np.timedelta64(6 * 3600 + 1, "s"))
        assert Timedelta("06:00:01.01") == conv(
            np.timedelta64(1000 * (6 * 3600 + 1) + 10, "ms")
        )

        assert Timedelta("- 1days, 00:00:01") == conv(-d1 + np.timedelta64(1, "s"))
        assert Timedelta("1days, 06:00:01") == conv(
            d1 + np.timedelta64(6 * 3600 + 1, "s")
        )
        assert Timedelta("1days, 06:00:01.01") == conv(
            d1 + np.timedelta64(1000 * (6 * 3600 + 1) + 10, "ms")
        )

        # invalid
        with pytest.raises(ValueError):
            Timedelta("- 1days, 00")

    def test_overflow(self):
        # GH 9442
        s = Series(pd.date_range("20130101", periods=100000, freq="H"))
        s[0] += Timedelta("1s 1ms")

        # mean
        result = (s - s.min()).mean()
        expected = Timedelta((TimedeltaIndex((s - s.min())).asi8 / len(s)).sum())

        # the computation is converted to float so
        # might be some loss of precision
        assert np.allclose(result.value / 1000, expected.value / 1000)

        # sum
        msg = "overflow in timedelta operation"
        with pytest.raises(ValueError, match=msg):
            (s - s.min()).sum()
        s1 = s[0:10000]
        with pytest.raises(ValueError, match=msg):
            (s1 - s1.min()).sum()
        s2 = s[0:1000]
        result = (s2 - s2.min()).sum()

    def test_pickle(self):

        v = Timedelta("1 days 10:11:12.0123456")
        v_p = tm.round_trip_pickle(v)
        assert v == v_p

    def test_timedelta_hash_equality(self):
        # GH 11129
        v = Timedelta(1, "D")
        td = timedelta(days=1)
        assert hash(v) == hash(td)

        d = {td: 2}
        assert d[v] == 2

        tds = timedelta_range("1 second", periods=20)
        assert all(hash(td) == hash(td.to_pytimedelta()) for td in tds)

        # python timedeltas drop ns resolution
        ns_td = Timedelta(1, "ns")
        assert hash(ns_td) != hash(ns_td.to_pytimedelta())

    def test_implementation_limits(self):
        min_td = Timedelta(Timedelta.min)
        max_td = Timedelta(Timedelta.max)

        # GH 12727
        # timedelta limits correspond to int64 boundaries
        assert min_td.value == np.iinfo(np.int64).min + 1
        assert max_td.value == np.iinfo(np.int64).max

        # Beyond lower limit, a NAT before the Overflow
        assert (min_td - Timedelta(1, "ns")) is NaT

        with pytest.raises(OverflowError):
            min_td - Timedelta(2, "ns")

        with pytest.raises(OverflowError):
            max_td + Timedelta(1, "ns")

        # Same tests using the internal nanosecond values
        td = Timedelta(min_td.value - 1, "ns")
        assert td is NaT

        with pytest.raises(OverflowError):
            Timedelta(min_td.value - 2, "ns")

        with pytest.raises(OverflowError):
            Timedelta(max_td.value + 1, "ns")

    def test_total_seconds_precision(self):
        # GH 19458
        assert Timedelta("30S").total_seconds() == 30.0
        assert Timedelta("0").total_seconds() == 0.0
        assert Timedelta("-2S").total_seconds() == -2.0
        assert Timedelta("5.324S").total_seconds() == 5.324
        assert (Timedelta("30S").total_seconds() - 30.0) < 1e-20
        assert (30.0 - Timedelta("30S").total_seconds()) < 1e-20

    def test_timedelta_arithmetic(self):
        data = Series(["nat", "32 days"], dtype="timedelta64[ns]")
        deltas = [timedelta(days=1), Timedelta(1, unit="D")]
        for delta in deltas:
            result_method = data.add(delta)
            result_operator = data + delta
            expected = Series(["nat", "33 days"], dtype="timedelta64[ns]")
            tm.assert_series_equal(result_operator, expected)
            tm.assert_series_equal(result_method, expected)

            result_method = data.sub(delta)
            result_operator = data - delta
            expected = Series(["nat", "31 days"], dtype="timedelta64[ns]")
            tm.assert_series_equal(result_operator, expected)
            tm.assert_series_equal(result_method, expected)
            # GH 9396
            result_method = data.div(delta)
            result_operator = data / delta
            expected = Series([np.nan, 32.0], dtype="float64")
            tm.assert_series_equal(result_operator, expected)
            tm.assert_series_equal(result_method, expected)

    def test_apply_to_timedelta(self):
        timedelta_NaT = to_timedelta("NaT")

        list_of_valid_strings = ["00:00:01", "00:00:02"]
        a = to_timedelta(list_of_valid_strings)
        b = Series(list_of_valid_strings).apply(to_timedelta)
        # Can't compare until apply on a Series gives the correct dtype
        # assert_series_equal(a, b)

        list_of_strings = ["00:00:01", np.nan, NaT, timedelta_NaT]

        # TODO: unused?
        a = to_timedelta(list_of_strings)  # noqa
        b = Series(list_of_strings).apply(to_timedelta)  # noqa
        # Can't compare until apply on a Series gives the correct dtype
        # assert_series_equal(a, b)

    def test_components(self):
        rng = timedelta_range("1 days, 10:11:12", periods=2, freq="s")
        rng.components

        # with nat
        s = Series(rng)
        s[1] = np.nan

        result = s.dt.components
        assert not result.iloc[0].isna().all()
        assert result.iloc[1].isna().all()

    def test_resolution_string(self):
        assert Timedelta(days=1).resolution_string == "D"
        assert Timedelta(days=1, hours=6).resolution_string == "H"
        assert Timedelta(days=1, minutes=6).resolution_string == "T"
        assert Timedelta(days=1, seconds=6).resolution_string == "S"
        assert Timedelta(days=1, milliseconds=6).resolution_string == "L"
        assert Timedelta(days=1, microseconds=6).resolution_string == "U"
        assert Timedelta(days=1, nanoseconds=6).resolution_string == "N"

    def test_resolution_deprecated(self):
        # GH#21344
        td = Timedelta(days=4, hours=3)
        result = td.resolution
        assert result == Timedelta(nanoseconds=1)

        # Check that the attribute is available on the class, mirroring
        #  the stdlib timedelta behavior
        result = Timedelta.resolution
        assert result == Timedelta(nanoseconds=1)


@pytest.mark.parametrize(
    "value, expected",
    [
        (Timedelta("10S"), True),
        (Timedelta("-10S"), True),
        (Timedelta(10, unit="ns"), True),
        (Timedelta(0, unit="ns"), False),
        (Timedelta(-10, unit="ns"), True),
        (Timedelta(None), True),
        (NaT, True),
    ],
)
def test_truthiness(value, expected):
    # https://github.com/pandas-dev/pandas/issues/21484
    assert bool(value) is expected