done

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_as_unit.py

@@ -0,0 +1,86 @@
+import pytest
+
+from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
+from pandas.errors import OutOfBoundsDatetime
+
+from pandas import Timestamp
+
+
+class TestTimestampAsUnit:
+    def test_as_unit(self):
+        ts = Timestamp("1970-01-01").as_unit("ns")
+        assert ts.unit == "ns"
+
+        assert ts.as_unit("ns") is ts
+
+        res = ts.as_unit("us")
+        assert res._value == ts._value // 1000
+        assert res._creso == NpyDatetimeUnit.NPY_FR_us.value
+
+        rt = res.as_unit("ns")
+        assert rt._value == ts._value
+        assert rt._creso == ts._creso
+
+        res = ts.as_unit("ms")
+        assert res._value == ts._value // 1_000_000
+        assert res._creso == NpyDatetimeUnit.NPY_FR_ms.value
+
+        rt = res.as_unit("ns")
+        assert rt._value == ts._value
+        assert rt._creso == ts._creso
+
+        res = ts.as_unit("s")
+        assert res._value == ts._value // 1_000_000_000
+        assert res._creso == NpyDatetimeUnit.NPY_FR_s.value
+
+        rt = res.as_unit("ns")
+        assert rt._value == ts._value
+        assert rt._creso == ts._creso
+
+    def test_as_unit_overflows(self):
+        # microsecond that would be just out of bounds for nano
+        us = 9223372800000000
+        ts = Timestamp._from_value_and_reso(us, NpyDatetimeUnit.NPY_FR_us.value, None)
+
+        msg = "Cannot cast 2262-04-12 00:00:00 to unit='ns' without overflow"
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            ts.as_unit("ns")
+
+        res = ts.as_unit("ms")
+        assert res._value == us // 1000
+        assert res._creso == NpyDatetimeUnit.NPY_FR_ms.value
+
+    def test_as_unit_rounding(self):
+        ts = Timestamp(1_500_000)  # i.e. 1500 microseconds
+        res = ts.as_unit("ms")
+
+        expected = Timestamp(1_000_000)  # i.e. 1 millisecond
+        assert res == expected
+
+        assert res._creso == NpyDatetimeUnit.NPY_FR_ms.value
+        assert res._value == 1
+
+        with pytest.raises(ValueError, match="Cannot losslessly convert units"):
+            ts.as_unit("ms", round_ok=False)
+
+    def test_as_unit_non_nano(self):
+        # case where we are going neither to nor from nano
+        ts = Timestamp("1970-01-02").as_unit("ms")
+        assert ts.year == 1970
+        assert ts.month == 1
+        assert ts.day == 2
+        assert ts.hour == ts.minute == ts.second == ts.microsecond == ts.nanosecond == 0
+
+        res = ts.as_unit("s")
+        assert res._value == 24 * 3600
+        assert res.year == 1970
+        assert res.month == 1
+        assert res.day == 2
+        assert (
+            res.hour
+            == res.minute
+            == res.second
+            == res.microsecond
+            == res.nanosecond
+            == 0
+        )

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_normalize.py

@@ -0,0 +1,22 @@
+import pytest
+
+from pandas._libs.tslibs import Timestamp
+from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
+
+
+class TestTimestampNormalize:
+    @pytest.mark.parametrize("arg", ["2013-11-30", "2013-11-30 12:00:00"])
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_normalize(self, tz_naive_fixture, arg, unit):
+        tz = tz_naive_fixture
+        ts = Timestamp(arg, tz=tz).as_unit(unit)
+        result = ts.normalize()
+        expected = Timestamp("2013-11-30", tz=tz)
+        assert result == expected
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+    def test_normalize_pre_epoch_dates(self):
+        # GH: 36294
+        result = Timestamp("1969-01-01 09:00:00").normalize()
+        expected = Timestamp("1969-01-01 00:00:00")
+        assert result == expected

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_replace.py

@@ -0,0 +1,193 @@
+from datetime import datetime
+
+from dateutil.tz import gettz
+import numpy as np
+import pytest
+import pytz
+
+from pandas._libs.tslibs import (
+    OutOfBoundsDatetime,
+    Timestamp,
+    conversion,
+)
+from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
+import pandas.util._test_decorators as td
+
+import pandas._testing as tm
+
+
+class TestTimestampReplace:
+    def test_replace_out_of_pydatetime_bounds(self):
+        # GH#50348
+        ts = Timestamp("2016-01-01").as_unit("ns")
+
+        msg = "Out of bounds timestamp: 99999-01-01 00:00:00 with frequency 'ns'"
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            ts.replace(year=99_999)
+
+        ts = ts.as_unit("ms")
+        result = ts.replace(year=99_999)
+        assert result.year == 99_999
+        assert result._value == Timestamp(np.datetime64("99999-01-01", "ms"))._value
+
+    def test_replace_non_nano(self):
+        ts = Timestamp._from_value_and_reso(
+            91514880000000000, NpyDatetimeUnit.NPY_FR_us.value, None
+        )
+        assert ts.to_pydatetime() == datetime(4869, 12, 28)
+
+        result = ts.replace(year=4900)
+        assert result._creso == ts._creso
+        assert result.to_pydatetime() == datetime(4900, 12, 28)
+
+    def test_replace_naive(self):
+        # GH#14621, GH#7825
+        ts = Timestamp("2016-01-01 09:00:00")
+        result = ts.replace(hour=0)
+        expected = Timestamp("2016-01-01 00:00:00")
+        assert result == expected
+
+    def test_replace_aware(self, tz_aware_fixture):
+        tz = tz_aware_fixture
+        # GH#14621, GH#7825
+        # replacing datetime components with and w/o presence of a timezone
+        ts = Timestamp("2016-01-01 09:00:00", tz=tz)
+        result = ts.replace(hour=0)
+        expected = Timestamp("2016-01-01 00:00:00", tz=tz)
+        assert result == expected
+
+    def test_replace_preserves_nanos(self, tz_aware_fixture):
+        tz = tz_aware_fixture
+        # GH#14621, GH#7825
+        ts = Timestamp("2016-01-01 09:00:00.000000123", tz=tz)
+        result = ts.replace(hour=0)
+        expected = Timestamp("2016-01-01 00:00:00.000000123", tz=tz)
+        assert result == expected
+
+    def test_replace_multiple(self, tz_aware_fixture):
+        tz = tz_aware_fixture
+        # GH#14621, GH#7825
+        # replacing datetime components with and w/o presence of a timezone
+        # test all
+        ts = Timestamp("2016-01-01 09:00:00.000000123", tz=tz)
+        result = ts.replace(
+            year=2015,
+            month=2,
+            day=2,
+            hour=0,
+            minute=5,
+            second=5,
+            microsecond=5,
+            nanosecond=5,
+        )
+        expected = Timestamp("2015-02-02 00:05:05.000005005", tz=tz)
+        assert result == expected
+
+    def test_replace_invalid_kwarg(self, tz_aware_fixture):
+        tz = tz_aware_fixture
+        # GH#14621, GH#7825
+        ts = Timestamp("2016-01-01 09:00:00.000000123", tz=tz)
+        msg = r"replace\(\) got an unexpected keyword argument"
+        with pytest.raises(TypeError, match=msg):
+            ts.replace(foo=5)
+
+    def test_replace_integer_args(self, tz_aware_fixture):
+        tz = tz_aware_fixture
+        # GH#14621, GH#7825
+        ts = Timestamp("2016-01-01 09:00:00.000000123", tz=tz)
+        msg = "value must be an integer, received <class 'float'> for hour"
+        with pytest.raises(ValueError, match=msg):
+            ts.replace(hour=0.1)
+
+    def test_replace_tzinfo_equiv_tz_localize_none(self):
+        # GH#14621, GH#7825
+        # assert conversion to naive is the same as replacing tzinfo with None
+        ts = Timestamp("2013-11-03 01:59:59.999999-0400", tz="US/Eastern")
+        assert ts.tz_localize(None) == ts.replace(tzinfo=None)
+
+    @td.skip_if_windows
+    def test_replace_tzinfo(self):
+        # GH#15683
+        dt = datetime(2016, 3, 27, 1)
+        tzinfo = pytz.timezone("CET").localize(dt, is_dst=False).tzinfo
+
+        result_dt = dt.replace(tzinfo=tzinfo)
+        result_pd = Timestamp(dt).replace(tzinfo=tzinfo)
+
+        # datetime.timestamp() converts in the local timezone
+        with tm.set_timezone("UTC"):
+            assert result_dt.timestamp() == result_pd.timestamp()
+
+        assert result_dt == result_pd
+        assert result_dt == result_pd.to_pydatetime()
+
+        result_dt = dt.replace(tzinfo=tzinfo).replace(tzinfo=None)
+        result_pd = Timestamp(dt).replace(tzinfo=tzinfo).replace(tzinfo=None)
+
+        # datetime.timestamp() converts in the local timezone
+        with tm.set_timezone("UTC"):
+            assert result_dt.timestamp() == result_pd.timestamp()
+
+        assert result_dt == result_pd
+        assert result_dt == result_pd.to_pydatetime()
+
+    @pytest.mark.parametrize(
+        "tz, normalize",
+        [
+            (pytz.timezone("US/Eastern"), lambda x: x.tzinfo.normalize(x)),
+            (gettz("US/Eastern"), lambda x: x),
+        ],
+    )
+    def test_replace_across_dst(self, tz, normalize):
+        # GH#18319 check that 1) timezone is correctly normalized and
+        # 2) that hour is not incorrectly changed by this normalization
+        ts_naive = Timestamp("2017-12-03 16:03:30")
+        ts_aware = conversion.localize_pydatetime(ts_naive, tz)
+
+        # Preliminary sanity-check
+        assert ts_aware == normalize(ts_aware)
+
+        # Replace across DST boundary
+        ts2 = ts_aware.replace(month=6)
+
+        # Check that `replace` preserves hour literal
+        assert (ts2.hour, ts2.minute) == (ts_aware.hour, ts_aware.minute)
+
+        # Check that post-replace object is appropriately normalized
+        ts2b = normalize(ts2)
+        assert ts2 == ts2b
+
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_replace_dst_border(self, unit):
+        # Gh 7825
+        t = Timestamp("2013-11-3", tz="America/Chicago").as_unit(unit)
+        result = t.replace(hour=3)
+        expected = Timestamp("2013-11-3 03:00:00", tz="America/Chicago")
+        assert result == expected
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+    @pytest.mark.parametrize("fold", [0, 1])
+    @pytest.mark.parametrize("tz", ["dateutil/Europe/London", "Europe/London"])
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_replace_dst_fold(self, fold, tz, unit):
+        # GH 25017
+        d = datetime(2019, 10, 27, 2, 30)
+        ts = Timestamp(d, tz=tz).as_unit(unit)
+        result = ts.replace(hour=1, fold=fold)
+        expected = Timestamp(datetime(2019, 10, 27, 1, 30)).tz_localize(
+            tz, ambiguous=not fold
+        )
+        assert result == expected
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+    @pytest.mark.parametrize("fold", [0, 1])
+    def test_replace_preserves_fold(self, fold):
+        # GH#37610. Check that replace preserves Timestamp fold property
+        tz = gettz("Europe/Moscow")
+
+        ts = Timestamp(
+            year=2009, month=10, day=25, hour=2, minute=30, fold=fold, tzinfo=tz
+        )
+        ts_replaced = ts.replace(second=1)
+
+        assert ts_replaced.fold == fold

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_round.py

@@ -0,0 +1,383 @@
+from hypothesis import (
+    given,
+    strategies as st,
+)
+import numpy as np
+import pytest
+import pytz
+
+from pandas._libs import lib
+from pandas._libs.tslibs import (
+    NaT,
+    OutOfBoundsDatetime,
+    Timedelta,
+    Timestamp,
+    iNaT,
+    to_offset,
+)
+from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
+from pandas._libs.tslibs.period import INVALID_FREQ_ERR_MSG
+
+import pandas._testing as tm
+
+
+class TestTimestampRound:
+    def test_round_division_by_zero_raises(self):
+        ts = Timestamp("2016-01-01")
+
+        msg = "Division by zero in rounding"
+        with pytest.raises(ValueError, match=msg):
+            ts.round("0ns")
+
+    @pytest.mark.parametrize(
+        "timestamp, freq, expected",
+        [
+            ("20130101 09:10:11", "D", "20130101"),
+            ("20130101 19:10:11", "D", "20130102"),
+            ("20130201 12:00:00", "D", "20130202"),
+            ("20130104 12:00:00", "D", "20130105"),
+            ("2000-01-05 05:09:15.13", "D", "2000-01-05 00:00:00"),
+            ("2000-01-05 05:09:15.13", "h", "2000-01-05 05:00:00"),
+            ("2000-01-05 05:09:15.13", "s", "2000-01-05 05:09:15"),
+        ],
+    )
+    def test_round_frequencies(self, timestamp, freq, expected):
+        dt = Timestamp(timestamp)
+        result = dt.round(freq)
+        expected = Timestamp(expected)
+        assert result == expected
+
+    def test_round_tzaware(self):
+        dt = Timestamp("20130101 09:10:11", tz="US/Eastern")
+        result = dt.round("D")
+        expected = Timestamp("20130101", tz="US/Eastern")
+        assert result == expected
+
+        dt = Timestamp("20130101 09:10:11", tz="US/Eastern")
+        result = dt.round("s")
+        assert result == dt
+
+    def test_round_30min(self):
+        # round
+        dt = Timestamp("20130104 12:32:00")
+        result = dt.round("30Min")
+        expected = Timestamp("20130104 12:30:00")
+        assert result == expected
+
+    def test_round_subsecond(self):
+        # GH#14440 & GH#15578
+        result = Timestamp("2016-10-17 12:00:00.0015").round("ms")
+        expected = Timestamp("2016-10-17 12:00:00.002000")
+        assert result == expected
+
+        result = Timestamp("2016-10-17 12:00:00.00149").round("ms")
+        expected = Timestamp("2016-10-17 12:00:00.001000")
+        assert result == expected
+
+        ts = Timestamp("2016-10-17 12:00:00.0015")
+        for freq in ["us", "ns"]:
+            assert ts == ts.round(freq)
+
+        result = Timestamp("2016-10-17 12:00:00.001501031").round("10ns")
+        expected = Timestamp("2016-10-17 12:00:00.001501030")
+        assert result == expected
+
+    def test_round_nonstandard_freq(self):
+        with tm.assert_produces_warning(False):
+            Timestamp("2016-10-17 12:00:00.001501031").round("1010ns")
+
+    def test_round_invalid_arg(self):
+        stamp = Timestamp("2000-01-05 05:09:15.13")
+        with pytest.raises(ValueError, match=INVALID_FREQ_ERR_MSG):
+            stamp.round("foo")
+
+    @pytest.mark.parametrize(
+        "test_input, rounder, freq, expected",
+        [
+            ("2117-01-01 00:00:45", "floor", "15s", "2117-01-01 00:00:45"),
+            ("2117-01-01 00:00:45", "ceil", "15s", "2117-01-01 00:00:45"),
+            (
+                "2117-01-01 00:00:45.000000012",
+                "floor",
+                "10ns",
+                "2117-01-01 00:00:45.000000010",
+            ),
+            (
+                "1823-01-01 00:00:01.000000012",
+                "ceil",
+                "10ns",
+                "1823-01-01 00:00:01.000000020",
+            ),
+            ("1823-01-01 00:00:01", "floor", "1s", "1823-01-01 00:00:01"),
+            ("1823-01-01 00:00:01", "ceil", "1s", "1823-01-01 00:00:01"),
+            ("NaT", "floor", "1s", "NaT"),
+            ("NaT", "ceil", "1s", "NaT"),
+        ],
+    )
+    def test_ceil_floor_edge(self, test_input, rounder, freq, expected):
+        dt = Timestamp(test_input)
+        func = getattr(dt, rounder)
+        result = func(freq)
+
+        if dt is NaT:
+            assert result is NaT
+        else:
+            expected = Timestamp(expected)
+            assert result == expected
+
+    @pytest.mark.parametrize(
+        "test_input, freq, expected",
+        [
+            ("2018-01-01 00:02:06", "2s", "2018-01-01 00:02:06"),
+            ("2018-01-01 00:02:00", "2min", "2018-01-01 00:02:00"),
+            ("2018-01-01 00:04:00", "4min", "2018-01-01 00:04:00"),
+            ("2018-01-01 00:15:00", "15min", "2018-01-01 00:15:00"),
+            ("2018-01-01 00:20:00", "20min", "2018-01-01 00:20:00"),
+            ("2018-01-01 03:00:00", "3h", "2018-01-01 03:00:00"),
+        ],
+    )
+    @pytest.mark.parametrize("rounder", ["ceil", "floor", "round"])
+    def test_round_minute_freq(self, test_input, freq, expected, rounder):
+        # Ensure timestamps that shouldn't round dont!
+        # GH#21262
+
+        dt = Timestamp(test_input)
+        expected = Timestamp(expected)
+        func = getattr(dt, rounder)
+        result = func(freq)
+        assert result == expected
+
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_ceil(self, unit):
+        dt = Timestamp("20130101 09:10:11").as_unit(unit)
+        result = dt.ceil("D")
+        expected = Timestamp("20130102")
+        assert result == expected
+        assert result._creso == dt._creso
+
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_floor(self, unit):
+        dt = Timestamp("20130101 09:10:11").as_unit(unit)
+        result = dt.floor("D")
+        expected = Timestamp("20130101")
+        assert result == expected
+        assert result._creso == dt._creso
+
+    @pytest.mark.parametrize("method", ["ceil", "round", "floor"])
+    @pytest.mark.parametrize(
+        "unit",
+        ["ns", "us", "ms", "s"],
+    )
+    def test_round_dst_border_ambiguous(self, method, unit):
+        # GH 18946 round near "fall back" DST
+        ts = Timestamp("2017-10-29 00:00:00", tz="UTC").tz_convert("Europe/Madrid")
+        ts = ts.as_unit(unit)
+        #
+        result = getattr(ts, method)("h", ambiguous=True)
+        assert result == ts
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+        result = getattr(ts, method)("h", ambiguous=False)
+        expected = Timestamp("2017-10-29 01:00:00", tz="UTC").tz_convert(
+            "Europe/Madrid"
+        )
+        assert result == expected
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+        result = getattr(ts, method)("h", ambiguous="NaT")
+        assert result is NaT
+
+        msg = "Cannot infer dst time"
+        with pytest.raises(pytz.AmbiguousTimeError, match=msg):
+            getattr(ts, method)("h", ambiguous="raise")
+
+    @pytest.mark.parametrize(
+        "method, ts_str, freq",
+        [
+            ["ceil", "2018-03-11 01:59:00-0600", "5min"],
+            ["round", "2018-03-11 01:59:00-0600", "5min"],
+            ["floor", "2018-03-11 03:01:00-0500", "2h"],
+        ],
+    )
+    @pytest.mark.parametrize(
+        "unit",
+        ["ns", "us", "ms", "s"],
+    )
+    def test_round_dst_border_nonexistent(self, method, ts_str, freq, unit):
+        # GH 23324 round near "spring forward" DST
+        ts = Timestamp(ts_str, tz="America/Chicago").as_unit(unit)
+        result = getattr(ts, method)(freq, nonexistent="shift_forward")
+        expected = Timestamp("2018-03-11 03:00:00", tz="America/Chicago")
+        assert result == expected
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+        result = getattr(ts, method)(freq, nonexistent="NaT")
+        assert result is NaT
+
+        msg = "2018-03-11 02:00:00"
+        with pytest.raises(pytz.NonExistentTimeError, match=msg):
+            getattr(ts, method)(freq, nonexistent="raise")
+
+    @pytest.mark.parametrize(
+        "timestamp",
+        [
+            "2018-01-01 0:0:0.124999360",
+            "2018-01-01 0:0:0.125000367",
+            "2018-01-01 0:0:0.125500",
+            "2018-01-01 0:0:0.126500",
+            "2018-01-01 12:00:00",
+            "2019-01-01 12:00:00",
+        ],
+    )
+    @pytest.mark.parametrize(
+        "freq",
+        [
+            "2ns",
+            "3ns",
+            "4ns",
+            "5ns",
+            "6ns",
+            "7ns",
+            "250ns",
+            "500ns",
+            "750ns",
+            "1us",
+            "19us",
+            "250us",
+            "500us",
+            "750us",
+            "1s",
+            "2s",
+            "3s",
+            "1D",
+        ],
+    )
+    def test_round_int64(self, timestamp, freq):
+        # check that all rounding modes are accurate to int64 precision
+        # see GH#22591
+        dt = Timestamp(timestamp).as_unit("ns")
+        unit = to_offset(freq).nanos
+
+        # test floor
+        result = dt.floor(freq)
+        assert result._value % unit == 0, f"floor not a {freq} multiple"
+        assert 0 <= dt._value - result._value < unit, "floor error"
+
+        # test ceil
+        result = dt.ceil(freq)
+        assert result._value % unit == 0, f"ceil not a {freq} multiple"
+        assert 0 <= result._value - dt._value < unit, "ceil error"
+
+        # test round
+        result = dt.round(freq)
+        assert result._value % unit == 0, f"round not a {freq} multiple"
+        assert abs(result._value - dt._value) <= unit // 2, "round error"
+        if unit % 2 == 0 and abs(result._value - dt._value) == unit // 2:
+            # round half to even
+            assert result._value // unit % 2 == 0, "round half to even error"
+
+    def test_round_implementation_bounds(self):
+        # See also: analogous test for Timedelta
+        result = Timestamp.min.ceil("s")
+        expected = Timestamp(1677, 9, 21, 0, 12, 44)
+        assert result == expected
+
+        result = Timestamp.max.floor("s")
+        expected = Timestamp.max - Timedelta(854775807)
+        assert result == expected
+
+        msg = "Cannot round 1677-09-21 00:12:43.145224193 to freq=<Second>"
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            Timestamp.min.floor("s")
+
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            Timestamp.min.round("s")
+
+        msg = "Cannot round 2262-04-11 23:47:16.854775807 to freq=<Second>"
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            Timestamp.max.ceil("s")
+
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            Timestamp.max.round("s")
+
+    @given(val=st.integers(iNaT + 1, lib.i8max))
+    @pytest.mark.parametrize(
+        "method", [Timestamp.round, Timestamp.floor, Timestamp.ceil]
+    )
+    def test_round_sanity(self, val, method):
+        cls = Timestamp
+        err_cls = OutOfBoundsDatetime
+
+        val = np.int64(val)
+        ts = cls(val)
+
+        def checker(ts, nanos, unit):
+            # First check that we do raise in cases where we should
+            if nanos == 1:
+                pass
+            else:
+                div, mod = divmod(ts._value, nanos)
+                diff = int(nanos - mod)
+                lb = ts._value - mod
+                assert lb <= ts._value  # i.e. no overflows with python ints
+                ub = ts._value + diff
+                assert ub > ts._value  # i.e. no overflows with python ints
+
+                msg = "without overflow"
+                if mod == 0:
+                    # We should never be raising in this
+                    pass
+                elif method is cls.ceil:
+                    if ub > cls.max._value:
+                        with pytest.raises(err_cls, match=msg):
+                            method(ts, unit)
+                        return
+                elif method is cls.floor:
+                    if lb < cls.min._value:
+                        with pytest.raises(err_cls, match=msg):
+                            method(ts, unit)
+                        return
+                elif mod >= diff:
+                    if ub > cls.max._value:
+                        with pytest.raises(err_cls, match=msg):
+                            method(ts, unit)
+                        return
+                elif lb < cls.min._value:
+                    with pytest.raises(err_cls, match=msg):
+                        method(ts, unit)
+                    return
+
+            res = method(ts, unit)
+
+            td = res - ts
+            diff = abs(td._value)
+            assert diff < nanos
+            assert res._value % nanos == 0
+
+            if method is cls.round:
+                assert diff <= nanos / 2
+            elif method is cls.floor:
+                assert res <= ts
+            elif method is cls.ceil:
+                assert res >= ts
+
+        nanos = 1
+        checker(ts, nanos, "ns")
+
+        nanos = 1000
+        checker(ts, nanos, "us")
+
+        nanos = 1_000_000
+        checker(ts, nanos, "ms")
+
+        nanos = 1_000_000_000
+        checker(ts, nanos, "s")
+
+        nanos = 60 * 1_000_000_000
+        checker(ts, nanos, "min")
+
+        nanos = 60 * 60 * 1_000_000_000
+        checker(ts, nanos, "h")
+
+        nanos = 24 * 60 * 60 * 1_000_000_000
+        checker(ts, nanos, "D")

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_timestamp_method.py

@@ -0,0 +1,31 @@
+# NB: This is for the Timestamp.timestamp *method* specifically, not
+# the Timestamp class in general.
+
+from pytz import utc
+
+from pandas._libs.tslibs import Timestamp
+import pandas.util._test_decorators as td
+
+import pandas._testing as tm
+
+
+class TestTimestampMethod:
+    @td.skip_if_windows
+    def test_timestamp(self, fixed_now_ts):
+        # GH#17329
+        # tz-naive --> treat it as if it were UTC for purposes of timestamp()
+        ts = fixed_now_ts
+        uts = ts.replace(tzinfo=utc)
+        assert ts.timestamp() == uts.timestamp()
+
+        tsc = Timestamp("2014-10-11 11:00:01.12345678", tz="US/Central")
+        utsc = tsc.tz_convert("UTC")
+
+        # utsc is a different representation of the same time
+        assert tsc.timestamp() == utsc.timestamp()
+
+        # datetime.timestamp() converts in the local timezone
+        with tm.set_timezone("UTC"):
+            # should agree with datetime.timestamp method
+            dt = ts.to_pydatetime()
+            assert dt.timestamp() == ts.timestamp()

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_to_julian_date.py

@@ -0,0 +1,28 @@
+from pandas import Timestamp
+
+
+class TestTimestampToJulianDate:
+    def test_compare_1700(self):
+        ts = Timestamp("1700-06-23")
+        res = ts.to_julian_date()
+        assert res == 2_342_145.5
+
+    def test_compare_2000(self):
+        ts = Timestamp("2000-04-12")
+        res = ts.to_julian_date()
+        assert res == 2_451_646.5
+
+    def test_compare_2100(self):
+        ts = Timestamp("2100-08-12")
+        res = ts.to_julian_date()
+        assert res == 2_488_292.5
+
+    def test_compare_hour01(self):
+        ts = Timestamp("2000-08-12T01:00:00")
+        res = ts.to_julian_date()
+        assert res == 2_451_768.5416666666666666
+
+    def test_compare_hour13(self):
+        ts = Timestamp("2000-08-12T13:00:00")
+        res = ts.to_julian_date()
+        assert res == 2_451_769.0416666666666666

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_to_pydatetime.py

@@ -0,0 +1,81 @@
+from datetime import (
+    datetime,
+    timedelta,
+)
+
+import pytz
+
+from pandas._libs.tslibs.timezones import dateutil_gettz as gettz
+import pandas.util._test_decorators as td
+
+from pandas import Timestamp
+import pandas._testing as tm
+
+
+class TestTimestampToPyDatetime:
+    def test_to_pydatetime_fold(self):
+        # GH#45087
+        tzstr = "dateutil/usr/share/zoneinfo/America/Chicago"
+        ts = Timestamp(year=2013, month=11, day=3, hour=1, minute=0, fold=1, tz=tzstr)
+        dt = ts.to_pydatetime()
+        assert dt.fold == 1
+
+    def test_to_pydatetime_nonzero_nano(self):
+        ts = Timestamp("2011-01-01 9:00:00.123456789")
+
+        # Warn the user of data loss (nanoseconds).
+        with tm.assert_produces_warning(UserWarning):
+            expected = datetime(2011, 1, 1, 9, 0, 0, 123456)
+            result = ts.to_pydatetime()
+            assert result == expected
+
+    def test_timestamp_to_datetime(self):
+        stamp = Timestamp("20090415", tz="US/Eastern")
+        dtval = stamp.to_pydatetime()
+        assert stamp == dtval
+        assert stamp.tzinfo == dtval.tzinfo
+
+    def test_timestamp_to_pydatetime_dateutil(self):
+        stamp = Timestamp("20090415", tz="dateutil/US/Eastern")
+        dtval = stamp.to_pydatetime()
+        assert stamp == dtval
+        assert stamp.tzinfo == dtval.tzinfo
+
+    def test_timestamp_to_pydatetime_explicit_pytz(self):
+        stamp = Timestamp("20090415", tz=pytz.timezone("US/Eastern"))
+        dtval = stamp.to_pydatetime()
+        assert stamp == dtval
+        assert stamp.tzinfo == dtval.tzinfo
+
+    @td.skip_if_windows
+    def test_timestamp_to_pydatetime_explicit_dateutil(self):
+        stamp = Timestamp("20090415", tz=gettz("US/Eastern"))
+        dtval = stamp.to_pydatetime()
+        assert stamp == dtval
+        assert stamp.tzinfo == dtval.tzinfo
+
+    def test_to_pydatetime_bijective(self):
+        # Ensure that converting to datetime and back only loses precision
+        # by going from nanoseconds to microseconds.
+        exp_warning = None if Timestamp.max.nanosecond == 0 else UserWarning
+        with tm.assert_produces_warning(exp_warning):
+            pydt_max = Timestamp.max.to_pydatetime()
+
+        assert (
+            Timestamp(pydt_max).as_unit("ns")._value / 1000
+            == Timestamp.max._value / 1000
+        )
+
+        exp_warning = None if Timestamp.min.nanosecond == 0 else UserWarning
+        with tm.assert_produces_warning(exp_warning):
+            pydt_min = Timestamp.min.to_pydatetime()
+
+        # The next assertion can be enabled once GH#39221 is merged
+        #  assert pydt_min < Timestamp.min  # this is bc nanos are dropped
+        tdus = timedelta(microseconds=1)
+        assert pydt_min + tdus > Timestamp.min
+
+        assert (
+            Timestamp(pydt_min + tdus).as_unit("ns")._value / 1000
+            == Timestamp.min._value / 1000
+        )

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_tz_convert.py

@@ -0,0 +1,51 @@
+import dateutil
+import pytest
+
+from pandas._libs.tslibs import timezones
+import pandas.util._test_decorators as td
+
+from pandas import Timestamp
+
+
+class TestTimestampTZConvert:
+    @pytest.mark.parametrize("tzstr", ["US/Eastern", "dateutil/US/Eastern"])
+    def test_astimezone(self, tzstr):
+        # astimezone is an alias for tz_convert, so keep it with
+        # the tz_convert tests
+        utcdate = Timestamp("3/11/2012 22:00", tz="UTC")
+        expected = utcdate.tz_convert(tzstr)
+        result = utcdate.astimezone(tzstr)
+        assert expected == result
+        assert isinstance(result, Timestamp)
+
+    @pytest.mark.parametrize(
+        "stamp",
+        [
+            "2014-02-01 09:00",
+            "2014-07-08 09:00",
+            "2014-11-01 17:00",
+            "2014-11-05 00:00",
+        ],
+    )
+    def test_tz_convert_roundtrip(self, stamp, tz_aware_fixture):
+        tz = tz_aware_fixture
+
+        ts = Timestamp(stamp, tz="UTC")
+        converted = ts.tz_convert(tz)
+
+        reset = converted.tz_convert(None)
+        assert reset == Timestamp(stamp)
+        assert reset.tzinfo is None
+        assert reset == converted.tz_convert("UTC").tz_localize(None)
+
+    @td.skip_if_windows
+    def test_tz_convert_utc_with_system_utc(self):
+        # from system utc to real utc
+        ts = Timestamp("2001-01-05 11:56", tz=timezones.maybe_get_tz("dateutil/UTC"))
+        # check that the time hasn't changed.
+        assert ts == ts.tz_convert(dateutil.tz.tzutc())
+
+        # from system utc to real utc
+        ts = Timestamp("2001-01-05 11:56", tz=timezones.maybe_get_tz("dateutil/UTC"))
+        # check that the time hasn't changed.
+        assert ts == ts.tz_convert(dateutil.tz.tzutc())

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/methods/test_tz_localize.py

@@ -0,0 +1,351 @@
+from datetime import timedelta
+import re
+
+from dateutil.tz import gettz
+import pytest
+import pytz
+from pytz.exceptions import (
+    AmbiguousTimeError,
+    NonExistentTimeError,
+)
+
+from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
+from pandas.errors import OutOfBoundsDatetime
+
+from pandas import (
+    NaT,
+    Timestamp,
+)
+
+try:
+    from zoneinfo import ZoneInfo
+except ImportError:
+    # Cannot assign to a type
+    ZoneInfo = None  # type: ignore[misc, assignment]
+
+
+class TestTimestampTZLocalize:
+    @pytest.mark.skip_ubsan
+    def test_tz_localize_pushes_out_of_bounds(self):
+        # GH#12677
+        # tz_localize that pushes away from the boundary is OK
+        msg = (
+            f"Converting {Timestamp.min.strftime('%Y-%m-%d %H:%M:%S')} "
+            f"underflows past {Timestamp.min}"
+        )
+        pac = Timestamp.min.tz_localize("US/Pacific")
+        assert pac._value > Timestamp.min._value
+        pac.tz_convert("Asia/Tokyo")  # tz_convert doesn't change value
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            Timestamp.min.tz_localize("Asia/Tokyo")
+
+        # tz_localize that pushes away from the boundary is OK
+        msg = (
+            f"Converting {Timestamp.max.strftime('%Y-%m-%d %H:%M:%S')} "
+            f"overflows past {Timestamp.max}"
+        )
+        tokyo = Timestamp.max.tz_localize("Asia/Tokyo")
+        assert tokyo._value < Timestamp.max._value
+        tokyo.tz_convert("US/Pacific")  # tz_convert doesn't change value
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            Timestamp.max.tz_localize("US/Pacific")
+
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_tz_localize_ambiguous_bool(self, unit):
+        # make sure that we are correctly accepting bool values as ambiguous
+        # GH#14402
+        ts = Timestamp("2015-11-01 01:00:03").as_unit(unit)
+        expected0 = Timestamp("2015-11-01 01:00:03-0500", tz="US/Central")
+        expected1 = Timestamp("2015-11-01 01:00:03-0600", tz="US/Central")
+
+        msg = "Cannot infer dst time from 2015-11-01 01:00:03"
+        with pytest.raises(pytz.AmbiguousTimeError, match=msg):
+            ts.tz_localize("US/Central")
+
+        with pytest.raises(pytz.AmbiguousTimeError, match=msg):
+            ts.tz_localize("dateutil/US/Central")
+
+        if ZoneInfo is not None:
+            try:
+                tz = ZoneInfo("US/Central")
+            except KeyError:
+                # no tzdata
+                pass
+            else:
+                with pytest.raises(pytz.AmbiguousTimeError, match=msg):
+                    ts.tz_localize(tz)
+
+        result = ts.tz_localize("US/Central", ambiguous=True)
+        assert result == expected0
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+        result = ts.tz_localize("US/Central", ambiguous=False)
+        assert result == expected1
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+    def test_tz_localize_ambiguous(self):
+        ts = Timestamp("2014-11-02 01:00")
+        ts_dst = ts.tz_localize("US/Eastern", ambiguous=True)
+        ts_no_dst = ts.tz_localize("US/Eastern", ambiguous=False)
+
+        assert ts_no_dst._value - ts_dst._value == 3600
+        msg = re.escape(
+            "'ambiguous' parameter must be one of: "
+            "True, False, 'NaT', 'raise' (default)"
+        )
+        with pytest.raises(ValueError, match=msg):
+            ts.tz_localize("US/Eastern", ambiguous="infer")
+
+        # GH#8025
+        msg = "Cannot localize tz-aware Timestamp, use tz_convert for conversions"
+        with pytest.raises(TypeError, match=msg):
+            Timestamp("2011-01-01", tz="US/Eastern").tz_localize("Asia/Tokyo")
+
+        msg = "Cannot convert tz-naive Timestamp, use tz_localize to localize"
+        with pytest.raises(TypeError, match=msg):
+            Timestamp("2011-01-01").tz_convert("Asia/Tokyo")
+
+    @pytest.mark.parametrize(
+        "stamp, tz",
+        [
+            ("2015-03-08 02:00", "US/Eastern"),
+            ("2015-03-08 02:30", "US/Pacific"),
+            ("2015-03-29 02:00", "Europe/Paris"),
+            ("2015-03-29 02:30", "Europe/Belgrade"),
+        ],
+    )
+    def test_tz_localize_nonexistent(self, stamp, tz):
+        # GH#13057
+        ts = Timestamp(stamp)
+        with pytest.raises(NonExistentTimeError, match=stamp):
+            ts.tz_localize(tz)
+        # GH 22644
+        with pytest.raises(NonExistentTimeError, match=stamp):
+            ts.tz_localize(tz, nonexistent="raise")
+        assert ts.tz_localize(tz, nonexistent="NaT") is NaT
+
+    @pytest.mark.parametrize(
+        "stamp, tz, forward_expected, backward_expected",
+        [
+            (
+                "2015-03-29 02:00:00",
+                "Europe/Warsaw",
+                "2015-03-29 03:00:00",
+                "2015-03-29 01:59:59",
+            ),  # utc+1 -> utc+2
+            (
+                "2023-03-12 02:00:00",
+                "America/Los_Angeles",
+                "2023-03-12 03:00:00",
+                "2023-03-12 01:59:59",
+            ),  # utc-8 -> utc-7
+            (
+                "2023-03-26 01:00:00",
+                "Europe/London",
+                "2023-03-26 02:00:00",
+                "2023-03-26 00:59:59",
+            ),  # utc+0 -> utc+1
+            (
+                "2023-03-26 00:00:00",
+                "Atlantic/Azores",
+                "2023-03-26 01:00:00",
+                "2023-03-25 23:59:59",
+            ),  # utc-1 -> utc+0
+        ],
+    )
+    def test_tz_localize_nonexistent_shift(
+        self, stamp, tz, forward_expected, backward_expected
+    ):
+        ts = Timestamp(stamp)
+        forward_ts = ts.tz_localize(tz, nonexistent="shift_forward")
+        assert forward_ts == Timestamp(forward_expected, tz=tz)
+        backward_ts = ts.tz_localize(tz, nonexistent="shift_backward")
+        assert backward_ts == Timestamp(backward_expected, tz=tz)
+
+    def test_tz_localize_ambiguous_raise(self):
+        # GH#13057
+        ts = Timestamp("2015-11-1 01:00")
+        msg = "Cannot infer dst time from 2015-11-01 01:00:00,"
+        with pytest.raises(AmbiguousTimeError, match=msg):
+            ts.tz_localize("US/Pacific", ambiguous="raise")
+
+    def test_tz_localize_nonexistent_invalid_arg(self, warsaw):
+        # GH 22644
+        tz = warsaw
+        ts = Timestamp("2015-03-29 02:00:00")
+        msg = (
+            "The nonexistent argument must be one of 'raise', 'NaT', "
+            "'shift_forward', 'shift_backward' or a timedelta object"
+        )
+        with pytest.raises(ValueError, match=msg):
+            ts.tz_localize(tz, nonexistent="foo")
+
+    @pytest.mark.parametrize(
+        "stamp",
+        [
+            "2014-02-01 09:00",
+            "2014-07-08 09:00",
+            "2014-11-01 17:00",
+            "2014-11-05 00:00",
+        ],
+    )
+    def test_tz_localize_roundtrip(self, stamp, tz_aware_fixture):
+        tz = tz_aware_fixture
+        ts = Timestamp(stamp)
+        localized = ts.tz_localize(tz)
+        assert localized == Timestamp(stamp, tz=tz)
+
+        msg = "Cannot localize tz-aware Timestamp"
+        with pytest.raises(TypeError, match=msg):
+            localized.tz_localize(tz)
+
+        reset = localized.tz_localize(None)
+        assert reset == ts
+        assert reset.tzinfo is None
+
+    def test_tz_localize_ambiguous_compat(self):
+        # validate that pytz and dateutil are compat for dst
+        # when the transition happens
+        naive = Timestamp("2013-10-27 01:00:00")
+
+        pytz_zone = "Europe/London"
+        dateutil_zone = "dateutil/Europe/London"
+        result_pytz = naive.tz_localize(pytz_zone, ambiguous=False)
+        result_dateutil = naive.tz_localize(dateutil_zone, ambiguous=False)
+        assert result_pytz._value == result_dateutil._value
+        assert result_pytz._value == 1382835600
+
+        # fixed ambiguous behavior
+        # see gh-14621, GH#45087
+        assert result_pytz.to_pydatetime().tzname() == "GMT"
+        assert result_dateutil.to_pydatetime().tzname() == "GMT"
+        assert str(result_pytz) == str(result_dateutil)
+
+        # 1 hour difference
+        result_pytz = naive.tz_localize(pytz_zone, ambiguous=True)
+        result_dateutil = naive.tz_localize(dateutil_zone, ambiguous=True)
+        assert result_pytz._value == result_dateutil._value
+        assert result_pytz._value == 1382832000
+
+        # see gh-14621
+        assert str(result_pytz) == str(result_dateutil)
+        assert (
+            result_pytz.to_pydatetime().tzname()
+            == result_dateutil.to_pydatetime().tzname()
+        )
+
+    @pytest.mark.parametrize(
+        "tz",
+        [
+            pytz.timezone("US/Eastern"),
+            gettz("US/Eastern"),
+            "US/Eastern",
+            "dateutil/US/Eastern",
+        ],
+    )
+    def test_timestamp_tz_localize(self, tz):
+        stamp = Timestamp("3/11/2012 04:00")
+
+        result = stamp.tz_localize(tz)
+        expected = Timestamp("3/11/2012 04:00", tz=tz)
+        assert result.hour == expected.hour
+        assert result == expected
+
+    @pytest.mark.parametrize(
+        "start_ts, tz, end_ts, shift",
+        [
+            ["2015-03-29 02:20:00", "Europe/Warsaw", "2015-03-29 03:00:00", "forward"],
+            [
+                "2015-03-29 02:20:00",
+                "Europe/Warsaw",
+                "2015-03-29 01:59:59.999999999",
+                "backward",
+            ],
+            [
+                "2015-03-29 02:20:00",
+                "Europe/Warsaw",
+                "2015-03-29 03:20:00",
+                timedelta(hours=1),
+            ],
+            [
+                "2015-03-29 02:20:00",
+                "Europe/Warsaw",
+                "2015-03-29 01:20:00",
+                timedelta(hours=-1),
+            ],
+            ["2018-03-11 02:33:00", "US/Pacific", "2018-03-11 03:00:00", "forward"],
+            [
+                "2018-03-11 02:33:00",
+                "US/Pacific",
+                "2018-03-11 01:59:59.999999999",
+                "backward",
+            ],
+            [
+                "2018-03-11 02:33:00",
+                "US/Pacific",
+                "2018-03-11 03:33:00",
+                timedelta(hours=1),
+            ],
+            [
+                "2018-03-11 02:33:00",
+                "US/Pacific",
+                "2018-03-11 01:33:00",
+                timedelta(hours=-1),
+            ],
+        ],
+    )
+    @pytest.mark.parametrize("tz_type", ["", "dateutil/"])
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_timestamp_tz_localize_nonexistent_shift(
+        self, start_ts, tz, end_ts, shift, tz_type, unit
+    ):
+        # GH 8917, 24466
+        tz = tz_type + tz
+        if isinstance(shift, str):
+            shift = "shift_" + shift
+        ts = Timestamp(start_ts).as_unit(unit)
+        result = ts.tz_localize(tz, nonexistent=shift)
+        expected = Timestamp(end_ts).tz_localize(tz)
+
+        if unit == "us":
+            assert result == expected.replace(nanosecond=0)
+        elif unit == "ms":
+            micros = expected.microsecond - expected.microsecond % 1000
+            assert result == expected.replace(microsecond=micros, nanosecond=0)
+        elif unit == "s":
+            assert result == expected.replace(microsecond=0, nanosecond=0)
+        else:
+            assert result == expected
+        assert result._creso == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
+
+    @pytest.mark.parametrize("offset", [-1, 1])
+    def test_timestamp_tz_localize_nonexistent_shift_invalid(self, offset, warsaw):
+        # GH 8917, 24466
+        tz = warsaw
+        ts = Timestamp("2015-03-29 02:20:00")
+        msg = "The provided timedelta will relocalize on a nonexistent time"
+        with pytest.raises(ValueError, match=msg):
+            ts.tz_localize(tz, nonexistent=timedelta(seconds=offset))
+
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_timestamp_tz_localize_nonexistent_NaT(self, warsaw, unit):
+        # GH 8917
+        tz = warsaw
+        ts = Timestamp("2015-03-29 02:20:00").as_unit(unit)
+        result = ts.tz_localize(tz, nonexistent="NaT")
+        assert result is NaT
+
+    @pytest.mark.parametrize("unit", ["ns", "us", "ms", "s"])
+    def test_timestamp_tz_localize_nonexistent_raise(self, warsaw, unit):
+        # GH 8917
+        tz = warsaw
+        ts = Timestamp("2015-03-29 02:20:00").as_unit(unit)
+        msg = "2015-03-29 02:20:00"
+        with pytest.raises(pytz.NonExistentTimeError, match=msg):
+            ts.tz_localize(tz, nonexistent="raise")
+        msg = (
+            "The nonexistent argument must be one of 'raise', 'NaT', "
+            "'shift_forward', 'shift_backward' or a timedelta object"
+        )
+        with pytest.raises(ValueError, match=msg):
+            ts.tz_localize(tz, nonexistent="foo")

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/test_arithmetic.py

@@ -0,0 +1,334 @@
+from datetime import (
+    datetime,
+    timedelta,
+    timezone,
+)
+
+from dateutil.tz import gettz
+import numpy as np
+import pytest
+import pytz
+
+from pandas._libs.tslibs import (
+    OutOfBoundsDatetime,
+    OutOfBoundsTimedelta,
+    Timedelta,
+    Timestamp,
+    offsets,
+    to_offset,
+)
+
+import pandas._testing as tm
+
+
+class TestTimestampArithmetic:
+    def test_overflow_offset(self):
+        # no overflow expected
+
+        stamp = Timestamp("2000/1/1")
+        offset_no_overflow = to_offset("D") * 100
+
+        expected = Timestamp("2000/04/10")
+        assert stamp + offset_no_overflow == expected
+
+        assert offset_no_overflow + stamp == expected
+
+        expected = Timestamp("1999/09/23")
+        assert stamp - offset_no_overflow == expected
+
+    def test_overflow_offset_raises(self):
+        # xref https://github.com/statsmodels/statsmodels/issues/3374
+        # ends up multiplying really large numbers which overflow
+
+        stamp = Timestamp("2017-01-13 00:00:00").as_unit("ns")
+        offset_overflow = 20169940 * offsets.Day(1)
+        lmsg2 = r"Cannot cast -?20169940 days \+?00:00:00 to unit='ns' without overflow"
+
+        with pytest.raises(OutOfBoundsTimedelta, match=lmsg2):
+            stamp + offset_overflow
+
+        with pytest.raises(OutOfBoundsTimedelta, match=lmsg2):
+            offset_overflow + stamp
+
+        with pytest.raises(OutOfBoundsTimedelta, match=lmsg2):
+            stamp - offset_overflow
+
+        # xref https://github.com/pandas-dev/pandas/issues/14080
+        # used to crash, so check for proper overflow exception
+
+        stamp = Timestamp("2000/1/1").as_unit("ns")
+        offset_overflow = to_offset("D") * 100**5
+
+        lmsg3 = (
+            r"Cannot cast -?10000000000 days \+?00:00:00 to unit='ns' without overflow"
+        )
+        with pytest.raises(OutOfBoundsTimedelta, match=lmsg3):
+            stamp + offset_overflow
+
+        with pytest.raises(OutOfBoundsTimedelta, match=lmsg3):
+            offset_overflow + stamp
+
+        with pytest.raises(OutOfBoundsTimedelta, match=lmsg3):
+            stamp - offset_overflow
+
+    def test_overflow_timestamp_raises(self):
+        # https://github.com/pandas-dev/pandas/issues/31774
+        msg = "Result is too large"
+        a = Timestamp("2101-01-01 00:00:00").as_unit("ns")
+        b = Timestamp("1688-01-01 00:00:00").as_unit("ns")
+
+        with pytest.raises(OutOfBoundsDatetime, match=msg):
+            a - b
+
+        # but we're OK for timestamp and datetime.datetime
+        assert (a - b.to_pydatetime()) == (a.to_pydatetime() - b)
+
+    def test_delta_preserve_nanos(self):
+        val = Timestamp(1337299200000000123)
+        result = val + timedelta(1)
+        assert result.nanosecond == val.nanosecond
+
+    def test_rsub_dtscalars(self, tz_naive_fixture):
+        # In particular, check that datetime64 - Timestamp works GH#28286
+        td = Timedelta(1235345642000)
+        ts = Timestamp("2021-01-01", tz=tz_naive_fixture)
+        other = ts + td
+
+        assert other - ts == td
+        assert other.to_pydatetime() - ts == td
+        if tz_naive_fixture is None:
+            assert other.to_datetime64() - ts == td
+        else:
+            msg = "Cannot subtract tz-naive and tz-aware datetime-like objects"
+            with pytest.raises(TypeError, match=msg):
+                other.to_datetime64() - ts
+
+    def test_timestamp_sub_datetime(self):
+        dt = datetime(2013, 10, 12)
+        ts = Timestamp(datetime(2013, 10, 13))
+        assert (ts - dt).days == 1
+        assert (dt - ts).days == -1
+
+    def test_subtract_tzaware_datetime(self):
+        t1 = Timestamp("2020-10-22T22:00:00+00:00")
+        t2 = datetime(2020, 10, 22, 22, tzinfo=timezone.utc)
+
+        result = t1 - t2
+
+        assert isinstance(result, Timedelta)
+        assert result == Timedelta("0 days")
+
+    def test_subtract_timestamp_from_different_timezone(self):
+        t1 = Timestamp("20130101").tz_localize("US/Eastern")
+        t2 = Timestamp("20130101").tz_localize("CET")
+
+        result = t1 - t2
+
+        assert isinstance(result, Timedelta)
+        assert result == Timedelta("0 days 06:00:00")
+
+    def test_subtracting_involving_datetime_with_different_tz(self):
+        t1 = datetime(2013, 1, 1, tzinfo=timezone(timedelta(hours=-5)))
+        t2 = Timestamp("20130101").tz_localize("CET")
+
+        result = t1 - t2
+
+        assert isinstance(result, Timedelta)
+        assert result == Timedelta("0 days 06:00:00")
+
+        result = t2 - t1
+        assert isinstance(result, Timedelta)
+        assert result == Timedelta("-1 days +18:00:00")
+
+    def test_subtracting_different_timezones(self, tz_aware_fixture):
+        t_raw = Timestamp("20130101")
+        t_UTC = t_raw.tz_localize("UTC")
+        t_diff = t_UTC.tz_convert(tz_aware_fixture) + Timedelta("0 days 05:00:00")
+
+        result = t_diff - t_UTC
+
+        assert isinstance(result, Timedelta)
+        assert result == Timedelta("0 days 05:00:00")
+
+    def test_addition_subtraction_types(self):
+        # Assert on the types resulting from Timestamp +/- various date/time
+        # objects
+        dt = datetime(2014, 3, 4)
+        td = timedelta(seconds=1)
+        ts = Timestamp(dt)
+
+        msg = "Addition/subtraction of integers"
+        with pytest.raises(TypeError, match=msg):
+            # GH#22535 add/sub with integers is deprecated
+            ts + 1
+        with pytest.raises(TypeError, match=msg):
+            ts - 1
+
+        # Timestamp + datetime not supported, though subtraction is supported
+        # and yields timedelta more tests in tseries/base/tests/test_base.py
+        assert type(ts - dt) == Timedelta
+        assert type(ts + td) == Timestamp
+        assert type(ts - td) == Timestamp
+
+        # Timestamp +/- datetime64 not supported, so not tested (could possibly
+        # assert error raised?)
+        td64 = np.timedelta64(1, "D")
+        assert type(ts + td64) == Timestamp
+        assert type(ts - td64) == Timestamp
+
+    @pytest.mark.parametrize(
+        "td", [Timedelta(hours=3), np.timedelta64(3, "h"), timedelta(hours=3)]
+    )
+    def test_radd_tdscalar(self, td, fixed_now_ts):
+        # GH#24775 timedelta64+Timestamp should not raise
+        ts = fixed_now_ts
+        assert td + ts == ts + td
+
+    @pytest.mark.parametrize(
+        "other,expected_difference",
+        [
+            (np.timedelta64(-123, "ns"), -123),
+            (np.timedelta64(1234567898, "ns"), 1234567898),
+            (np.timedelta64(-123, "us"), -123000),
+            (np.timedelta64(-123, "ms"), -123000000),
+        ],
+    )
+    def test_timestamp_add_timedelta64_unit(self, other, expected_difference):
+        now = datetime.now(timezone.utc)
+        ts = Timestamp(now).as_unit("ns")
+        result = ts + other
+        valdiff = result._value - ts._value
+        assert valdiff == expected_difference
+
+        ts2 = Timestamp(now)
+        assert ts2 + other == result
+
+    @pytest.mark.parametrize(
+        "ts",
+        [
+            Timestamp("1776-07-04"),
+            Timestamp("1776-07-04", tz="UTC"),
+        ],
+    )
+    @pytest.mark.parametrize(
+        "other",
+        [
+            1,
+            np.int64(1),
+            np.array([1, 2], dtype=np.int32),
+            np.array([3, 4], dtype=np.uint64),
+        ],
+    )
+    def test_add_int_with_freq(self, ts, other):
+        msg = "Addition/subtraction of integers and integer-arrays"
+        with pytest.raises(TypeError, match=msg):
+            ts + other
+        with pytest.raises(TypeError, match=msg):
+            other + ts
+
+        with pytest.raises(TypeError, match=msg):
+            ts - other
+
+        msg = "unsupported operand type"
+        with pytest.raises(TypeError, match=msg):
+            other - ts
+
+    @pytest.mark.parametrize("shape", [(6,), (2, 3)])
+    def test_addsub_m8ndarray(self, shape):
+        # GH#33296
+        ts = Timestamp("2020-04-04 15:45").as_unit("ns")
+        other = np.arange(6).astype("m8[h]").reshape(shape)
+
+        result = ts + other
+
+        ex_stamps = [ts + Timedelta(hours=n) for n in range(6)]
+        expected = np.array([x.asm8 for x in ex_stamps], dtype="M8[ns]").reshape(shape)
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = other + ts
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = ts - other
+        ex_stamps = [ts - Timedelta(hours=n) for n in range(6)]
+        expected = np.array([x.asm8 for x in ex_stamps], dtype="M8[ns]").reshape(shape)
+        tm.assert_numpy_array_equal(result, expected)
+
+        msg = r"unsupported operand type\(s\) for -: 'numpy.ndarray' and 'Timestamp'"
+        with pytest.raises(TypeError, match=msg):
+            other - ts
+
+    @pytest.mark.parametrize("shape", [(6,), (2, 3)])
+    def test_addsub_m8ndarray_tzaware(self, shape):
+        # GH#33296
+        ts = Timestamp("2020-04-04 15:45", tz="US/Pacific")
+
+        other = np.arange(6).astype("m8[h]").reshape(shape)
+
+        result = ts + other
+
+        ex_stamps = [ts + Timedelta(hours=n) for n in range(6)]
+        expected = np.array(ex_stamps).reshape(shape)
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = other + ts
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = ts - other
+        ex_stamps = [ts - Timedelta(hours=n) for n in range(6)]
+        expected = np.array(ex_stamps).reshape(shape)
+        tm.assert_numpy_array_equal(result, expected)
+
+        msg = r"unsupported operand type\(s\) for -: 'numpy.ndarray' and 'Timestamp'"
+        with pytest.raises(TypeError, match=msg):
+            other - ts
+
+    def test_subtract_different_utc_objects(self, utc_fixture, utc_fixture2):
+        # GH 32619
+        dt = datetime(2021, 1, 1)
+        ts1 = Timestamp(dt, tz=utc_fixture)
+        ts2 = Timestamp(dt, tz=utc_fixture2)
+        result = ts1 - ts2
+        expected = Timedelta(0)
+        assert result == expected
+
+    @pytest.mark.parametrize(
+        "tz",
+        [
+            pytz.timezone("US/Eastern"),
+            gettz("US/Eastern"),
+            "US/Eastern",
+            "dateutil/US/Eastern",
+        ],
+    )
+    def test_timestamp_add_timedelta_push_over_dst_boundary(self, tz):
+        # GH#1389
+
+        # 4 hours before DST transition
+        stamp = Timestamp("3/10/2012 22:00", tz=tz)
+
+        result = stamp + timedelta(hours=6)
+
+        # spring forward, + "7" hours
+        expected = Timestamp("3/11/2012 05:00", tz=tz)
+
+        assert result == expected
+
+
+class SubDatetime(datetime):
+    pass
+
+
+@pytest.mark.parametrize(
+    "lh,rh",
+    [
+        (SubDatetime(2000, 1, 1), Timedelta(hours=1)),
+        (Timedelta(hours=1), SubDatetime(2000, 1, 1)),
+    ],
+)
+def test_dt_subclass_add_timedelta(lh, rh):
+    # GH#25851
+    # ensure that subclassed datetime works for
+    # Timedelta operations
+    result = lh + rh
+    expected = SubDatetime(2000, 1, 1, 1)
+    assert result == expected

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/test_comparisons.py

@@ -0,0 +1,313 @@
+from datetime import (
+    datetime,
+    timedelta,
+)
+import operator
+
+import numpy as np
+import pytest
+
+from pandas import Timestamp
+import pandas._testing as tm
+
+
+class TestTimestampComparison:
+    def test_compare_non_nano_dt64(self):
+        # don't raise when converting dt64 to Timestamp in __richcmp__
+        dt = np.datetime64("1066-10-14")
+        ts = Timestamp(dt)
+
+        assert dt == ts
+
+    def test_comparison_dt64_ndarray(self):
+        ts = Timestamp("2021-01-01")
+        ts2 = Timestamp("2019-04-05")
+        arr = np.array([[ts.asm8, ts2.asm8]], dtype="M8[ns]")
+
+        result = ts == arr
+        expected = np.array([[True, False]], dtype=bool)
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = arr == ts
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = ts != arr
+        tm.assert_numpy_array_equal(result, ~expected)
+
+        result = arr != ts
+        tm.assert_numpy_array_equal(result, ~expected)
+
+        result = ts2 < arr
+        tm.assert_numpy_array_equal(result, expected)
+
+        result = arr < ts2
+        tm.assert_numpy_array_equal(result, np.array([[False, False]], dtype=bool))
+
+        result = ts2 <= arr
+        tm.assert_numpy_array_equal(result, np.array([[True, True]], dtype=bool))
+
+        result = arr <= ts2
+        tm.assert_numpy_array_equal(result, ~expected)
+
+        result = ts >= arr
+        tm.assert_numpy_array_equal(result, np.array([[True, True]], dtype=bool))
+
+        result = arr >= ts
+        tm.assert_numpy_array_equal(result, np.array([[True, False]], dtype=bool))
+
+    @pytest.mark.parametrize("reverse", [True, False])
+    def test_comparison_dt64_ndarray_tzaware(self, reverse, comparison_op):
+        ts = Timestamp("2021-01-01 00:00:00.00000", tz="UTC")
+        arr = np.array([ts.asm8, ts.asm8], dtype="M8[ns]")
+
+        left, right = ts, arr
+        if reverse:
+            left, right = arr, ts
+
+        if comparison_op is operator.eq:
+            expected = np.array([False, False], dtype=bool)
+            result = comparison_op(left, right)
+            tm.assert_numpy_array_equal(result, expected)
+        elif comparison_op is operator.ne:
+            expected = np.array([True, True], dtype=bool)
+            result = comparison_op(left, right)
+            tm.assert_numpy_array_equal(result, expected)
+        else:
+            msg = "Cannot compare tz-naive and tz-aware timestamps"
+            with pytest.raises(TypeError, match=msg):
+                comparison_op(left, right)
+
+    def test_comparison_object_array(self):
+        # GH#15183
+        ts = Timestamp("2011-01-03 00:00:00-0500", tz="US/Eastern")
+        other = Timestamp("2011-01-01 00:00:00-0500", tz="US/Eastern")
+        naive = Timestamp("2011-01-01 00:00:00")
+
+        arr = np.array([other, ts], dtype=object)
+        res = arr == ts
+        expected = np.array([False, True], dtype=bool)
+        assert (res == expected).all()
+
+        # 2D case
+        arr = np.array([[other, ts], [ts, other]], dtype=object)
+        res = arr != ts
+        expected = np.array([[True, False], [False, True]], dtype=bool)
+        assert res.shape == expected.shape
+        assert (res == expected).all()
+
+        # tzaware mismatch
+        arr = np.array([naive], dtype=object)
+        msg = "Cannot compare tz-naive and tz-aware timestamps"
+        with pytest.raises(TypeError, match=msg):
+            arr < ts
+
+    def test_comparison(self):
+        # 5-18-2012 00:00:00.000
+        stamp = 1337299200000000000
+
+        val = Timestamp(stamp)
+
+        assert val == val
+        assert not val != val
+        assert not val < val
+        assert val <= val
+        assert not val > val
+        assert val >= val
+
+        other = datetime(2012, 5, 18)
+        assert val == other
+        assert not val != other
+        assert not val < other
+        assert val <= other
+        assert not val > other
+        assert val >= other
+
+        other = Timestamp(stamp + 100)
+
+        assert val != other
+        assert val != other
+        assert val < other
+        assert val <= other
+        assert other > val
+        assert other >= val
+
+    def test_compare_invalid(self):
+        # GH#8058
+        val = Timestamp("20130101 12:01:02")
+        assert not val == "foo"
+        assert not val == 10.0
+        assert not val == 1
+        assert not val == []
+        assert not val == {"foo": 1}
+        assert not val == np.float64(1)
+        assert not val == np.int64(1)
+
+        assert val != "foo"
+        assert val != 10.0
+        assert val != 1
+        assert val != []
+        assert val != {"foo": 1}
+        assert val != np.float64(1)
+        assert val != np.int64(1)
+
+    @pytest.mark.parametrize("tz", [None, "US/Pacific"])
+    def test_compare_date(self, tz):
+        # GH#36131 comparing Timestamp with date object is deprecated
+        ts = Timestamp("2021-01-01 00:00:00.00000", tz=tz)
+        dt = ts.to_pydatetime().date()
+        # in 2.0 we disallow comparing pydate objects with Timestamps,
+        #  following the stdlib datetime behavior.
+
+        msg = "Cannot compare Timestamp with datetime.date"
+        for left, right in [(ts, dt), (dt, ts)]:
+            assert not left == right
+            assert left != right
+
+            with pytest.raises(TypeError, match=msg):
+                left < right
+            with pytest.raises(TypeError, match=msg):
+                left <= right
+            with pytest.raises(TypeError, match=msg):
+                left > right
+            with pytest.raises(TypeError, match=msg):
+                left >= right
+
+    def test_cant_compare_tz_naive_w_aware(self, utc_fixture):
+        # see GH#1404
+        a = Timestamp("3/12/2012")
+        b = Timestamp("3/12/2012", tz=utc_fixture)
+
+        msg = "Cannot compare tz-naive and tz-aware timestamps"
+        assert not a == b
+        assert a != b
+        with pytest.raises(TypeError, match=msg):
+            a < b
+        with pytest.raises(TypeError, match=msg):
+            a <= b
+        with pytest.raises(TypeError, match=msg):
+            a > b
+        with pytest.raises(TypeError, match=msg):
+            a >= b
+
+        assert not b == a
+        assert b != a
+        with pytest.raises(TypeError, match=msg):
+            b < a
+        with pytest.raises(TypeError, match=msg):
+            b <= a
+        with pytest.raises(TypeError, match=msg):
+            b > a
+        with pytest.raises(TypeError, match=msg):
+            b >= a
+
+        assert not a == b.to_pydatetime()
+        assert not a.to_pydatetime() == b
+
+    def test_timestamp_compare_scalars(self):
+        # case where ndim == 0
+        lhs = np.datetime64(datetime(2013, 12, 6))
+        rhs = Timestamp("now")
+        nat = Timestamp("nat")
+
+        ops = {"gt": "lt", "lt": "gt", "ge": "le", "le": "ge", "eq": "eq", "ne": "ne"}
+
+        for left, right in ops.items():
+            left_f = getattr(operator, left)
+            right_f = getattr(operator, right)
+            expected = left_f(lhs, rhs)
+
+            result = right_f(rhs, lhs)
+            assert result == expected
+
+            expected = left_f(rhs, nat)
+            result = right_f(nat, rhs)
+            assert result == expected
+
+    def test_timestamp_compare_with_early_datetime(self):
+        # e.g. datetime.min
+        stamp = Timestamp("2012-01-01")
+
+        assert not stamp == datetime.min
+        assert not stamp == datetime(1600, 1, 1)
+        assert not stamp == datetime(2700, 1, 1)
+        assert stamp != datetime.min
+        assert stamp != datetime(1600, 1, 1)
+        assert stamp != datetime(2700, 1, 1)
+        assert stamp > datetime(1600, 1, 1)
+        assert stamp >= datetime(1600, 1, 1)
+        assert stamp < datetime(2700, 1, 1)
+        assert stamp <= datetime(2700, 1, 1)
+
+        other = Timestamp.min.to_pydatetime(warn=False)
+        assert other - timedelta(microseconds=1) < Timestamp.min
+
+    def test_timestamp_compare_oob_dt64(self):
+        us = np.timedelta64(1, "us")
+        other = np.datetime64(Timestamp.min).astype("M8[us]")
+
+        # This may change if the implementation bound is dropped to match
+        #  DatetimeArray/DatetimeIndex GH#24124
+        assert Timestamp.min > other
+        # Note: numpy gets the reversed comparison wrong
+
+        other = np.datetime64(Timestamp.max).astype("M8[us]")
+        assert Timestamp.max > other  # not actually OOB
+        assert other < Timestamp.max
+
+        assert Timestamp.max < other + us
+        # Note: numpy gets the reversed comparison wrong
+
+        # GH-42794
+        other = datetime(9999, 9, 9)
+        assert Timestamp.min < other
+        assert other > Timestamp.min
+        assert Timestamp.max < other
+        assert other > Timestamp.max
+
+        other = datetime(1, 1, 1)
+        assert Timestamp.max > other
+        assert other < Timestamp.max
+        assert Timestamp.min > other
+        assert other < Timestamp.min
+
+    def test_compare_zerodim_array(self, fixed_now_ts):
+        # GH#26916
+        ts = fixed_now_ts
+        dt64 = np.datetime64("2016-01-01", "ns")
+        arr = np.array(dt64)
+        assert arr.ndim == 0
+
+        result = arr < ts
+        assert result is np.bool_(True)
+        result = arr > ts
+        assert result is np.bool_(False)
+
+
+def test_rich_comparison_with_unsupported_type():
+    # Comparisons with unsupported objects should return NotImplemented
+    # (it previously raised TypeError, see #24011)
+
+    class Inf:
+        def __lt__(self, o):
+            return False
+
+        def __le__(self, o):
+            return isinstance(o, Inf)
+
+        def __gt__(self, o):
+            return not isinstance(o, Inf)
+
+        def __ge__(self, o):
+            return True
+
+        def __eq__(self, other) -> bool:
+            return isinstance(other, Inf)
+
+    inf = Inf()
+    timestamp = Timestamp("2018-11-30")
+
+    for left, right in [(inf, timestamp), (timestamp, inf)]:
+        assert left > right or left < right
+        assert left >= right or left <= right
+        assert not left == right  # pylint: disable=unneeded-not
+        assert left != right

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/test_formats.py

@@ -0,0 +1,201 @@
+from datetime import datetime
+import pprint
+
+import dateutil.tz
+import pytest
+import pytz  # a test below uses pytz but only inside a `eval` call
+
+from pandas import Timestamp
+
+ts_no_ns = Timestamp(
+    year=2019,
+    month=5,
+    day=18,
+    hour=15,
+    minute=17,
+    second=8,
+    microsecond=132263,
+)
+ts_no_ns_year1 = Timestamp(
+    year=1,
+    month=5,
+    day=18,
+    hour=15,
+    minute=17,
+    second=8,
+    microsecond=132263,
+)
+ts_ns = Timestamp(
+    year=2019,
+    month=5,
+    day=18,
+    hour=15,
+    minute=17,
+    second=8,
+    microsecond=132263,
+    nanosecond=123,
+)
+ts_ns_tz = Timestamp(
+    year=2019,
+    month=5,
+    day=18,
+    hour=15,
+    minute=17,
+    second=8,
+    microsecond=132263,
+    nanosecond=123,
+    tz="UTC",
+)
+ts_no_us = Timestamp(
+    year=2019,
+    month=5,
+    day=18,
+    hour=15,
+    minute=17,
+    second=8,
+    microsecond=0,
+    nanosecond=123,
+)
+
+
+@pytest.mark.parametrize(
+    "ts, timespec, expected_iso",
+    [
+        (ts_no_ns, "auto", "2019-05-18T15:17:08.132263"),
+        (ts_no_ns, "seconds", "2019-05-18T15:17:08"),
+        (ts_no_ns, "nanoseconds", "2019-05-18T15:17:08.132263000"),
+        (ts_no_ns_year1, "seconds", "0001-05-18T15:17:08"),
+        (ts_no_ns_year1, "nanoseconds", "0001-05-18T15:17:08.132263000"),
+        (ts_ns, "auto", "2019-05-18T15:17:08.132263123"),
+        (ts_ns, "hours", "2019-05-18T15"),
+        (ts_ns, "minutes", "2019-05-18T15:17"),
+        (ts_ns, "seconds", "2019-05-18T15:17:08"),
+        (ts_ns, "milliseconds", "2019-05-18T15:17:08.132"),
+        (ts_ns, "microseconds", "2019-05-18T15:17:08.132263"),
+        (ts_ns, "nanoseconds", "2019-05-18T15:17:08.132263123"),
+        (ts_ns_tz, "auto", "2019-05-18T15:17:08.132263123+00:00"),
+        (ts_ns_tz, "hours", "2019-05-18T15+00:00"),
+        (ts_ns_tz, "minutes", "2019-05-18T15:17+00:00"),
+        (ts_ns_tz, "seconds", "2019-05-18T15:17:08+00:00"),
+        (ts_ns_tz, "milliseconds", "2019-05-18T15:17:08.132+00:00"),
+        (ts_ns_tz, "microseconds", "2019-05-18T15:17:08.132263+00:00"),
+        (ts_ns_tz, "nanoseconds", "2019-05-18T15:17:08.132263123+00:00"),
+        (ts_no_us, "auto", "2019-05-18T15:17:08.000000123"),
+    ],
+)
+def test_isoformat(ts, timespec, expected_iso):
+    assert ts.isoformat(timespec=timespec) == expected_iso
+
+
+class TestTimestampRendering:
+    timezones = ["UTC", "Asia/Tokyo", "US/Eastern", "dateutil/America/Los_Angeles"]
+
+    @pytest.mark.parametrize("tz", timezones)
+    @pytest.mark.parametrize("freq", ["D", "M", "S", "N"])
+    @pytest.mark.parametrize(
+        "date", ["2014-03-07", "2014-01-01 09:00", "2014-01-01 00:00:00.000000001"]
+    )
+    def test_repr(self, date, freq, tz):
+        # avoid to match with timezone name
+        freq_repr = f"'{freq}'"
+        if tz.startswith("dateutil"):
+            tz_repr = tz.replace("dateutil", "")
+        else:
+            tz_repr = tz
+
+        date_only = Timestamp(date)
+        assert date in repr(date_only)
+        assert tz_repr not in repr(date_only)
+        assert freq_repr not in repr(date_only)
+        assert date_only == eval(repr(date_only))
+
+        date_tz = Timestamp(date, tz=tz)
+        assert date in repr(date_tz)
+        assert tz_repr in repr(date_tz)
+        assert freq_repr not in repr(date_tz)
+        assert date_tz == eval(repr(date_tz))
+
+    def test_repr_utcoffset(self):
+        # This can cause the tz field to be populated, but it's redundant to
+        # include this information in the date-string.
+        date_with_utc_offset = Timestamp("2014-03-13 00:00:00-0400", tz=None)
+        assert "2014-03-13 00:00:00-0400" in repr(date_with_utc_offset)
+        assert "tzoffset" not in repr(date_with_utc_offset)
+        assert "UTC-04:00" in repr(date_with_utc_offset)
+        expr = repr(date_with_utc_offset)
+        assert date_with_utc_offset == eval(expr)
+
+    def test_timestamp_repr_pre1900(self):
+        # pre-1900
+        stamp = Timestamp("1850-01-01", tz="US/Eastern")
+        repr(stamp)
+
+        iso8601 = "1850-01-01 01:23:45.012345"
+        stamp = Timestamp(iso8601, tz="US/Eastern")
+        result = repr(stamp)
+        assert iso8601 in result
+
+    def test_pprint(self):
+        # GH#12622
+        nested_obj = {"foo": 1, "bar": [{"w": {"a": Timestamp("2011-01-01")}}] * 10}
+        result = pprint.pformat(nested_obj, width=50)
+        expected = r"""{'bar': [{'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}},
+         {'w': {'a': Timestamp('2011-01-01 00:00:00')}}],
+ 'foo': 1}"""
+        assert result == expected
+
+    def test_to_timestamp_repr_is_code(self):
+        zs = [
+            Timestamp("99-04-17 00:00:00", tz="UTC"),
+            Timestamp("2001-04-17 00:00:00", tz="UTC"),
+            Timestamp("2001-04-17 00:00:00", tz="America/Los_Angeles"),
+            Timestamp("2001-04-17 00:00:00", tz=None),
+        ]
+        for z in zs:
+            assert eval(repr(z)) == z
+
+    def test_repr_matches_pydatetime_no_tz(self):
+        dt_date = datetime(2013, 1, 2)
+        assert str(dt_date) == str(Timestamp(dt_date))
+
+        dt_datetime = datetime(2013, 1, 2, 12, 1, 3)
+        assert str(dt_datetime) == str(Timestamp(dt_datetime))
+
+        dt_datetime_us = datetime(2013, 1, 2, 12, 1, 3, 45)
+        assert str(dt_datetime_us) == str(Timestamp(dt_datetime_us))
+
+        ts_nanos_only = Timestamp(200)
+        assert str(ts_nanos_only) == "1970-01-01 00:00:00.000000200"
+
+        ts_nanos_micros = Timestamp(1200)
+        assert str(ts_nanos_micros) == "1970-01-01 00:00:00.000001200"
+
+    def test_repr_matches_pydatetime_tz_pytz(self):
+        dt_date = datetime(2013, 1, 2, tzinfo=pytz.utc)
+        assert str(dt_date) == str(Timestamp(dt_date))
+
+        dt_datetime = datetime(2013, 1, 2, 12, 1, 3, tzinfo=pytz.utc)
+        assert str(dt_datetime) == str(Timestamp(dt_datetime))
+
+        dt_datetime_us = datetime(2013, 1, 2, 12, 1, 3, 45, tzinfo=pytz.utc)
+        assert str(dt_datetime_us) == str(Timestamp(dt_datetime_us))
+
+    def test_repr_matches_pydatetime_tz_dateutil(self):
+        utc = dateutil.tz.tzutc()
+
+        dt_date = datetime(2013, 1, 2, tzinfo=utc)
+        assert str(dt_date) == str(Timestamp(dt_date))
+
+        dt_datetime = datetime(2013, 1, 2, 12, 1, 3, tzinfo=utc)
+        assert str(dt_datetime) == str(Timestamp(dt_datetime))
+
+        dt_datetime_us = datetime(2013, 1, 2, 12, 1, 3, 45, tzinfo=utc)
+        assert str(dt_datetime_us) == str(Timestamp(dt_datetime_us))

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/test_timestamp.py

@@ -0,0 +1,928 @@
+""" test the scalar Timestamp """
+
+import calendar
+from datetime import (
+    datetime,
+    timedelta,
+    timezone,
+)
+import locale
+import time
+import unicodedata
+
+from dateutil.tz import (
+    tzlocal,
+    tzutc,
+)
+from hypothesis import (
+    given,
+    strategies as st,
+)
+import numpy as np
+import pytest
+import pytz
+from pytz import utc
+
+from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
+from pandas._libs.tslibs.timezones import (
+    dateutil_gettz as gettz,
+    get_timezone,
+    maybe_get_tz,
+    tz_compare,
+)
+from pandas.compat import IS64
+
+from pandas import (
+    NaT,
+    Timedelta,
+    Timestamp,
+)
+import pandas._testing as tm
+
+from pandas.tseries import offsets
+from pandas.tseries.frequencies import to_offset
+
+
+class TestTimestampProperties:
+    def test_properties_business(self):
+        freq = to_offset("B")
+
+        ts = Timestamp("2017-10-01")
+        assert ts.dayofweek == 6
+        assert ts.day_of_week == 6
+        assert ts.is_month_start  # not a weekday
+        assert not freq.is_month_start(ts)
+        assert freq.is_month_start(ts + Timedelta(days=1))
+        assert not freq.is_quarter_start(ts)
+        assert freq.is_quarter_start(ts + Timedelta(days=1))
+
+        ts = Timestamp("2017-09-30")
+        assert ts.dayofweek == 5
+        assert ts.day_of_week == 5
+        assert ts.is_month_end
+        assert not freq.is_month_end(ts)
+        assert freq.is_month_end(ts - Timedelta(days=1))
+        assert ts.is_quarter_end
+        assert not freq.is_quarter_end(ts)
+        assert freq.is_quarter_end(ts - Timedelta(days=1))
+
+    @pytest.mark.parametrize(
+        "attr, expected",
+        [
+            ["year", 2014],
+            ["month", 12],
+            ["day", 31],
+            ["hour", 23],
+            ["minute", 59],
+            ["second", 0],
+            ["microsecond", 0],
+            ["nanosecond", 0],
+            ["dayofweek", 2],
+            ["day_of_week", 2],
+            ["quarter", 4],
+            ["dayofyear", 365],
+            ["day_of_year", 365],
+            ["week", 1],
+            ["daysinmonth", 31],
+        ],
+    )
+    @pytest.mark.parametrize("tz", [None, "US/Eastern"])
+    def test_fields(self, attr, expected, tz):
+        # GH 10050
+        # GH 13303
+        ts = Timestamp("2014-12-31 23:59:00", tz=tz)
+        result = getattr(ts, attr)
+        # that we are int like
+        assert isinstance(result, int)
+        assert result == expected
+
+    @pytest.mark.parametrize("tz", [None, "US/Eastern"])
+    def test_millisecond_raises(self, tz):
+        ts = Timestamp("2014-12-31 23:59:00", tz=tz)
+        msg = "'Timestamp' object has no attribute 'millisecond'"
+        with pytest.raises(AttributeError, match=msg):
+            ts.millisecond
+
+    @pytest.mark.parametrize(
+        "start", ["is_month_start", "is_quarter_start", "is_year_start"]
+    )
+    @pytest.mark.parametrize("tz", [None, "US/Eastern"])
+    def test_is_start(self, start, tz):
+        ts = Timestamp("2014-01-01 00:00:00", tz=tz)
+        assert getattr(ts, start)
+
+    @pytest.mark.parametrize("end", ["is_month_end", "is_year_end", "is_quarter_end"])
+    @pytest.mark.parametrize("tz", [None, "US/Eastern"])
+    def test_is_end(self, end, tz):
+        ts = Timestamp("2014-12-31 23:59:59", tz=tz)
+        assert getattr(ts, end)
+
+    # GH 12806
+    @pytest.mark.parametrize(
+        "data",
+        [Timestamp("2017-08-28 23:00:00"), Timestamp("2017-08-28 23:00:00", tz="EST")],
+    )
+    # error: Unsupported operand types for + ("List[None]" and "List[str]")
+    @pytest.mark.parametrize(
+        "time_locale", [None] + tm.get_locales()  # type: ignore[operator]
+    )
+    def test_names(self, data, time_locale):
+        # GH 17354
+        # Test .day_name(), .month_name
+        if time_locale is None:
+            expected_day = "Monday"
+            expected_month = "August"
+        else:
+            with tm.set_locale(time_locale, locale.LC_TIME):
+                expected_day = calendar.day_name[0].capitalize()
+                expected_month = calendar.month_name[8].capitalize()
+
+        result_day = data.day_name(time_locale)
+        result_month = data.month_name(time_locale)
+
+        # Work around https://github.com/pandas-dev/pandas/issues/22342
+        # different normalizations
+        expected_day = unicodedata.normalize("NFD", expected_day)
+        expected_month = unicodedata.normalize("NFD", expected_month)
+
+        result_day = unicodedata.normalize("NFD", result_day)
+        result_month = unicodedata.normalize("NFD", result_month)
+
+        assert result_day == expected_day
+        assert result_month == expected_month
+
+        # Test NaT
+        nan_ts = Timestamp(NaT)
+        assert np.isnan(nan_ts.day_name(time_locale))
+        assert np.isnan(nan_ts.month_name(time_locale))
+
+    def test_is_leap_year(self, tz_naive_fixture):
+        tz = tz_naive_fixture
+        if not IS64 and tz == tzlocal():
+            # https://github.com/dateutil/dateutil/issues/197
+            pytest.skip(
+                "tzlocal() on a 32 bit platform causes internal overflow errors"
+            )
+        # GH 13727
+        dt = Timestamp("2000-01-01 00:00:00", tz=tz)
+        assert dt.is_leap_year
+        assert isinstance(dt.is_leap_year, bool)
+
+        dt = Timestamp("1999-01-01 00:00:00", tz=tz)
+        assert not dt.is_leap_year
+
+        dt = Timestamp("2004-01-01 00:00:00", tz=tz)
+        assert dt.is_leap_year
+
+        dt = Timestamp("2100-01-01 00:00:00", tz=tz)
+        assert not dt.is_leap_year
+
+    def test_woy_boundary(self):
+        # make sure weeks at year boundaries are correct
+        d = datetime(2013, 12, 31)
+        result = Timestamp(d).week
+        expected = 1  # ISO standard
+        assert result == expected
+
+        d = datetime(2008, 12, 28)
+        result = Timestamp(d).week
+        expected = 52  # ISO standard
+        assert result == expected
+
+        d = datetime(2009, 12, 31)
+        result = Timestamp(d).week
+        expected = 53  # ISO standard
+        assert result == expected
+
+        d = datetime(2010, 1, 1)
+        result = Timestamp(d).week
+        expected = 53  # ISO standard
+        assert result == expected
+
+        d = datetime(2010, 1, 3)
+        result = Timestamp(d).week
+        expected = 53  # ISO standard
+        assert result == expected
+
+        result = np.array(
+            [
+                Timestamp(datetime(*args)).week
+                for args in [(2000, 1, 1), (2000, 1, 2), (2005, 1, 1), (2005, 1, 2)]
+            ]
+        )
+        assert (result == [52, 52, 53, 53]).all()
+
+    def test_resolution(self):
+        # GH#21336, GH#21365
+        dt = Timestamp("2100-01-01 00:00:00.000000000")
+        assert dt.resolution == Timedelta(nanoseconds=1)
+
+        # Check that the attribute is available on the class, mirroring
+        #  the stdlib datetime behavior
+        assert Timestamp.resolution == Timedelta(nanoseconds=1)
+
+        assert dt.as_unit("us").resolution == Timedelta(microseconds=1)
+        assert dt.as_unit("ms").resolution == Timedelta(milliseconds=1)
+        assert dt.as_unit("s").resolution == Timedelta(seconds=1)
+
+    @pytest.mark.parametrize(
+        "date_string, expected",
+        [
+            ("0000-2-29", 1),
+            ("0000-3-1", 2),
+            ("1582-10-14", 3),
+            ("-0040-1-1", 4),
+            ("2023-06-18", 6),
+        ],
+    )
+    def test_dow_historic(self, date_string, expected):
+        # GH 53738
+        ts = Timestamp(date_string)
+        dow = ts.weekday()
+        assert dow == expected
+
+    @given(
+        ts=st.datetimes(),
+        sign=st.sampled_from(["-", ""]),
+    )
+    def test_dow_parametric(self, ts, sign):
+        # GH 53738
+        ts = (
+            f"{sign}{str(ts.year).zfill(4)}"
+            f"-{str(ts.month).zfill(2)}"
+            f"-{str(ts.day).zfill(2)}"
+        )
+        result = Timestamp(ts).weekday()
+        expected = (
+            (np.datetime64(ts) - np.datetime64("1970-01-01")).astype("int64") - 4
+        ) % 7
+        assert result == expected
+
+
+class TestTimestamp:
+    @pytest.mark.parametrize("tz", [None, pytz.timezone("US/Pacific")])
+    def test_disallow_setting_tz(self, tz):
+        # GH#3746
+        ts = Timestamp("2010")
+        msg = "Cannot directly set timezone"
+        with pytest.raises(AttributeError, match=msg):
+            ts.tz = tz
+
+    def test_default_to_stdlib_utc(self):
+        assert Timestamp.utcnow().tz is timezone.utc
+        assert Timestamp.now("UTC").tz is timezone.utc
+        assert Timestamp("2016-01-01", tz="UTC").tz is timezone.utc
+
+    def test_tz(self):
+        tstr = "2014-02-01 09:00"
+        ts = Timestamp(tstr)
+        local = ts.tz_localize("Asia/Tokyo")
+        assert local.hour == 9
+        assert local == Timestamp(tstr, tz="Asia/Tokyo")
+        conv = local.tz_convert("US/Eastern")
+        assert conv == Timestamp("2014-01-31 19:00", tz="US/Eastern")
+        assert conv.hour == 19
+
+        # preserves nanosecond
+        ts = Timestamp(tstr) + offsets.Nano(5)
+        local = ts.tz_localize("Asia/Tokyo")
+        assert local.hour == 9
+        assert local.nanosecond == 5
+        conv = local.tz_convert("US/Eastern")
+        assert conv.nanosecond == 5
+        assert conv.hour == 19
+
+    def test_utc_z_designator(self):
+        assert get_timezone(Timestamp("2014-11-02 01:00Z").tzinfo) is timezone.utc
+
+    def test_asm8(self):
+        ns = [Timestamp.min._value, Timestamp.max._value, 1000]
+
+        for n in ns:
+            assert (
+                Timestamp(n).asm8.view("i8") == np.datetime64(n, "ns").view("i8") == n
+            )
+
+        assert Timestamp("nat").asm8.view("i8") == np.datetime64("nat", "ns").view("i8")
+
+    def test_class_ops(self):
+        def compare(x, y):
+            assert int((Timestamp(x)._value - Timestamp(y)._value) / 1e9) == 0
+
+        compare(Timestamp.now(), datetime.now())
+        compare(Timestamp.now("UTC"), datetime.now(pytz.timezone("UTC")))
+        compare(Timestamp.now("UTC"), datetime.now(tzutc()))
+        compare(Timestamp.utcnow(), datetime.now(timezone.utc))
+        compare(Timestamp.today(), datetime.today())
+        current_time = calendar.timegm(datetime.now().utctimetuple())
+
+        ts_utc = Timestamp.utcfromtimestamp(current_time)
+        assert ts_utc.timestamp() == current_time
+        compare(
+            Timestamp.fromtimestamp(current_time), datetime.fromtimestamp(current_time)
+        )
+        compare(
+            # Support tz kwarg in Timestamp.fromtimestamp
+            Timestamp.fromtimestamp(current_time, "UTC"),
+            datetime.fromtimestamp(current_time, utc),
+        )
+        compare(
+            # Support tz kwarg in Timestamp.fromtimestamp
+            Timestamp.fromtimestamp(current_time, tz="UTC"),
+            datetime.fromtimestamp(current_time, utc),
+        )
+
+        date_component = datetime.now(timezone.utc)
+        time_component = (date_component + timedelta(minutes=10)).time()
+        compare(
+            Timestamp.combine(date_component, time_component),
+            datetime.combine(date_component, time_component),
+        )
+
+    def test_basics_nanos(self):
+        val = np.int64(946_684_800_000_000_000).view("M8[ns]")
+        stamp = Timestamp(val.view("i8") + 500)
+        assert stamp.year == 2000
+        assert stamp.month == 1
+        assert stamp.microsecond == 0
+        assert stamp.nanosecond == 500
+
+        # GH 14415
+        val = np.iinfo(np.int64).min + 80_000_000_000_000
+        stamp = Timestamp(val)
+        assert stamp.year == 1677
+        assert stamp.month == 9
+        assert stamp.day == 21
+        assert stamp.microsecond == 145224
+        assert stamp.nanosecond == 192
+
+    def test_roundtrip(self):
+        # test value to string and back conversions
+        # further test accessors
+        base = Timestamp("20140101 00:00:00").as_unit("ns")
+
+        result = Timestamp(base._value + Timedelta("5ms")._value)
+        assert result == Timestamp(f"{base}.005000")
+        assert result.microsecond == 5000
+
+        result = Timestamp(base._value + Timedelta("5us")._value)
+        assert result == Timestamp(f"{base}.000005")
+        assert result.microsecond == 5
+
+        result = Timestamp(base._value + Timedelta("5ns")._value)
+        assert result == Timestamp(f"{base}.000000005")
+        assert result.nanosecond == 5
+        assert result.microsecond == 0
+
+        result = Timestamp(base._value + Timedelta("6ms 5us")._value)
+        assert result == Timestamp(f"{base}.006005")
+        assert result.microsecond == 5 + 6 * 1000
+
+        result = Timestamp(base._value + Timedelta("200ms 5us")._value)
+        assert result == Timestamp(f"{base}.200005")
+        assert result.microsecond == 5 + 200 * 1000
+
+    def test_hash_equivalent(self):
+        d = {datetime(2011, 1, 1): 5}
+        stamp = Timestamp(datetime(2011, 1, 1))
+        assert d[stamp] == 5
+
+    @pytest.mark.parametrize(
+        "timezone, year, month, day, hour",
+        [["America/Chicago", 2013, 11, 3, 1], ["America/Santiago", 2021, 4, 3, 23]],
+    )
+    def test_hash_timestamp_with_fold(self, timezone, year, month, day, hour):
+        # see gh-33931
+        test_timezone = gettz(timezone)
+        transition_1 = Timestamp(
+            year=year,
+            month=month,
+            day=day,
+            hour=hour,
+            minute=0,
+            fold=0,
+            tzinfo=test_timezone,
+        )
+        transition_2 = Timestamp(
+            year=year,
+            month=month,
+            day=day,
+            hour=hour,
+            minute=0,
+            fold=1,
+            tzinfo=test_timezone,
+        )
+        assert hash(transition_1) == hash(transition_2)
+
+
+class TestTimestampNsOperations:
+    def test_nanosecond_string_parsing(self):
+        ts = Timestamp("2013-05-01 07:15:45.123456789")
+        # GH 7878
+        expected_repr = "2013-05-01 07:15:45.123456789"
+        expected_value = 1_367_392_545_123_456_789
+        assert ts._value == expected_value
+        assert expected_repr in repr(ts)
+
+        ts = Timestamp("2013-05-01 07:15:45.123456789+09:00", tz="Asia/Tokyo")
+        assert ts._value == expected_value - 9 * 3600 * 1_000_000_000
+        assert expected_repr in repr(ts)
+
+        ts = Timestamp("2013-05-01 07:15:45.123456789", tz="UTC")
+        assert ts._value == expected_value
+        assert expected_repr in repr(ts)
+
+        ts = Timestamp("2013-05-01 07:15:45.123456789", tz="US/Eastern")
+        assert ts._value == expected_value + 4 * 3600 * 1_000_000_000
+        assert expected_repr in repr(ts)
+
+        # GH 10041
+        ts = Timestamp("20130501T071545.123456789")
+        assert ts._value == expected_value
+        assert expected_repr in repr(ts)
+
+    def test_nanosecond_timestamp(self):
+        # GH 7610
+        expected = 1_293_840_000_000_000_005
+        t = Timestamp("2011-01-01") + offsets.Nano(5)
+        assert repr(t) == "Timestamp('2011-01-01 00:00:00.000000005')"
+        assert t._value == expected
+        assert t.nanosecond == 5
+
+        t = Timestamp(t)
+        assert repr(t) == "Timestamp('2011-01-01 00:00:00.000000005')"
+        assert t._value == expected
+        assert t.nanosecond == 5
+
+        t = Timestamp("2011-01-01 00:00:00.000000005")
+        assert repr(t) == "Timestamp('2011-01-01 00:00:00.000000005')"
+        assert t._value == expected
+        assert t.nanosecond == 5
+
+        expected = 1_293_840_000_000_000_010
+        t = t + offsets.Nano(5)
+        assert repr(t) == "Timestamp('2011-01-01 00:00:00.000000010')"
+        assert t._value == expected
+        assert t.nanosecond == 10
+
+        t = Timestamp(t)
+        assert repr(t) == "Timestamp('2011-01-01 00:00:00.000000010')"
+        assert t._value == expected
+        assert t.nanosecond == 10
+
+        t = Timestamp("2011-01-01 00:00:00.000000010")
+        assert repr(t) == "Timestamp('2011-01-01 00:00:00.000000010')"
+        assert t._value == expected
+        assert t.nanosecond == 10
+
+
+class TestTimestampConversion:
+    def test_conversion(self):
+        # GH#9255
+        ts = Timestamp("2000-01-01").as_unit("ns")
+
+        result = ts.to_pydatetime()
+        expected = datetime(2000, 1, 1)
+        assert result == expected
+        assert type(result) == type(expected)
+
+        result = ts.to_datetime64()
+        expected = np.datetime64(ts._value, "ns")
+        assert result == expected
+        assert type(result) == type(expected)
+        assert result.dtype == expected.dtype
+
+    def test_to_period_tz_warning(self):
+        # GH#21333 make sure a warning is issued when timezone
+        # info is lost
+        ts = Timestamp("2009-04-15 16:17:18", tz="US/Eastern")
+        with tm.assert_produces_warning(UserWarning):
+            # warning that timezone info will be lost
+            ts.to_period("D")
+
+    def test_to_numpy_alias(self):
+        # GH 24653: alias .to_numpy() for scalars
+        ts = Timestamp(datetime.now())
+        assert ts.to_datetime64() == ts.to_numpy()
+
+        # GH#44460
+        msg = "dtype and copy arguments are ignored"
+        with pytest.raises(ValueError, match=msg):
+            ts.to_numpy("M8[s]")
+        with pytest.raises(ValueError, match=msg):
+            ts.to_numpy(copy=True)
+
+
+class TestNonNano:
+    @pytest.fixture(params=["s", "ms", "us"])
+    def reso(self, request):
+        return request.param
+
+    @pytest.fixture
+    def dt64(self, reso):
+        # cases that are in-bounds for nanosecond, so we can compare against
+        #  the existing implementation.
+        return np.datetime64("2016-01-01", reso)
+
+    @pytest.fixture
+    def ts(self, dt64):
+        return Timestamp._from_dt64(dt64)
+
+    @pytest.fixture
+    def ts_tz(self, ts, tz_aware_fixture):
+        tz = maybe_get_tz(tz_aware_fixture)
+        return Timestamp._from_value_and_reso(ts._value, ts._creso, tz)
+
+    def test_non_nano_construction(self, dt64, ts, reso):
+        assert ts._value == dt64.view("i8")
+
+        if reso == "s":
+            assert ts._creso == NpyDatetimeUnit.NPY_FR_s.value
+        elif reso == "ms":
+            assert ts._creso == NpyDatetimeUnit.NPY_FR_ms.value
+        elif reso == "us":
+            assert ts._creso == NpyDatetimeUnit.NPY_FR_us.value
+
+    def test_non_nano_fields(self, dt64, ts):
+        alt = Timestamp(dt64)
+
+        assert ts.year == alt.year
+        assert ts.month == alt.month
+        assert ts.day == alt.day
+        assert ts.hour == ts.minute == ts.second == ts.microsecond == 0
+        assert ts.nanosecond == 0
+
+        assert ts.to_julian_date() == alt.to_julian_date()
+        assert ts.weekday() == alt.weekday()
+        assert ts.isoweekday() == alt.isoweekday()
+
+    def test_start_end_fields(self, ts):
+        assert ts.is_year_start
+        assert ts.is_quarter_start
+        assert ts.is_month_start
+        assert not ts.is_year_end
+        assert not ts.is_month_end
+        assert not ts.is_month_end
+
+        # 2016-01-01 is a Friday, so is year/quarter/month start with this freq
+        assert ts.is_year_start
+        assert ts.is_quarter_start
+        assert ts.is_month_start
+        assert not ts.is_year_end
+        assert not ts.is_month_end
+        assert not ts.is_month_end
+
+    def test_day_name(self, dt64, ts):
+        alt = Timestamp(dt64)
+        assert ts.day_name() == alt.day_name()
+
+    def test_month_name(self, dt64, ts):
+        alt = Timestamp(dt64)
+        assert ts.month_name() == alt.month_name()
+
+    def test_tz_convert(self, ts):
+        ts = Timestamp._from_value_and_reso(ts._value, ts._creso, utc)
+
+        tz = pytz.timezone("US/Pacific")
+        result = ts.tz_convert(tz)
+
+        assert isinstance(result, Timestamp)
+        assert result._creso == ts._creso
+        assert tz_compare(result.tz, tz)
+
+    def test_repr(self, dt64, ts):
+        alt = Timestamp(dt64)
+
+        assert str(ts) == str(alt)
+        assert repr(ts) == repr(alt)
+
+    def test_comparison(self, dt64, ts):
+        alt = Timestamp(dt64)
+
+        assert ts == dt64
+        assert dt64 == ts
+        assert ts == alt
+        assert alt == ts
+
+        assert not ts != dt64
+        assert not dt64 != ts
+        assert not ts != alt
+        assert not alt != ts
+
+        assert not ts < dt64
+        assert not dt64 < ts
+        assert not ts < alt
+        assert not alt < ts
+
+        assert not ts > dt64
+        assert not dt64 > ts
+        assert not ts > alt
+        assert not alt > ts
+
+        assert ts >= dt64
+        assert dt64 >= ts
+        assert ts >= alt
+        assert alt >= ts
+
+        assert ts <= dt64
+        assert dt64 <= ts
+        assert ts <= alt
+        assert alt <= ts
+
+    def test_cmp_cross_reso(self):
+        # numpy gets this wrong because of silent overflow
+        dt64 = np.datetime64(9223372800, "s")  # won't fit in M8[ns]
+        ts = Timestamp._from_dt64(dt64)
+
+        # subtracting 3600*24 gives a datetime64 that _can_ fit inside the
+        #  nanosecond implementation bounds.
+        other = Timestamp(dt64 - 3600 * 24).as_unit("ns")
+        assert other < ts
+        assert other.asm8 > ts.asm8  # <- numpy gets this wrong
+        assert ts > other
+        assert ts.asm8 < other.asm8  # <- numpy gets this wrong
+        assert not other == ts
+        assert ts != other
+
+    @pytest.mark.xfail(reason="Dispatches to np.datetime64 which is wrong")
+    def test_cmp_cross_reso_reversed_dt64(self):
+        dt64 = np.datetime64(106752, "D")  # won't fit in M8[ns]
+        ts = Timestamp._from_dt64(dt64)
+        other = Timestamp(dt64 - 1)
+
+        assert other.asm8 < ts
+
+    def test_pickle(self, ts, tz_aware_fixture):
+        tz = tz_aware_fixture
+        tz = maybe_get_tz(tz)
+        ts = Timestamp._from_value_and_reso(ts._value, ts._creso, tz)
+        rt = tm.round_trip_pickle(ts)
+        assert rt._creso == ts._creso
+        assert rt == ts
+
+    def test_normalize(self, dt64, ts):
+        alt = Timestamp(dt64)
+        result = ts.normalize()
+        assert result._creso == ts._creso
+        assert result == alt.normalize()
+
+    def test_asm8(self, dt64, ts):
+        rt = ts.asm8
+        assert rt == dt64
+        assert rt.dtype == dt64.dtype
+
+    def test_to_numpy(self, dt64, ts):
+        res = ts.to_numpy()
+        assert res == dt64
+        assert res.dtype == dt64.dtype
+
+    def test_to_datetime64(self, dt64, ts):
+        res = ts.to_datetime64()
+        assert res == dt64
+        assert res.dtype == dt64.dtype
+
+    def test_timestamp(self, dt64, ts):
+        alt = Timestamp(dt64)
+        assert ts.timestamp() == alt.timestamp()
+
+    def test_to_period(self, dt64, ts):
+        alt = Timestamp(dt64)
+        assert ts.to_period("D") == alt.to_period("D")
+
+    @pytest.mark.parametrize(
+        "td", [timedelta(days=4), Timedelta(days=4), np.timedelta64(4, "D")]
+    )
+    def test_addsub_timedeltalike_non_nano(self, dt64, ts, td):
+        exp_reso = max(ts._creso, Timedelta(td)._creso)
+
+        result = ts - td
+        expected = Timestamp(dt64) - td
+        assert isinstance(result, Timestamp)
+        assert result._creso == exp_reso
+        assert result == expected
+
+        result = ts + td
+        expected = Timestamp(dt64) + td
+        assert isinstance(result, Timestamp)
+        assert result._creso == exp_reso
+        assert result == expected
+
+        result = td + ts
+        expected = td + Timestamp(dt64)
+        assert isinstance(result, Timestamp)
+        assert result._creso == exp_reso
+        assert result == expected
+
+    def test_addsub_offset(self, ts_tz):
+        # specifically non-Tick offset
+        off = offsets.YearEnd(1)
+        result = ts_tz + off
+
+        assert isinstance(result, Timestamp)
+        assert result._creso == ts_tz._creso
+        if ts_tz.month == 12 and ts_tz.day == 31:
+            assert result.year == ts_tz.year + 1
+        else:
+            assert result.year == ts_tz.year
+        assert result.day == 31
+        assert result.month == 12
+        assert tz_compare(result.tz, ts_tz.tz)
+
+        result = ts_tz - off
+
+        assert isinstance(result, Timestamp)
+        assert result._creso == ts_tz._creso
+        assert result.year == ts_tz.year - 1
+        assert result.day == 31
+        assert result.month == 12
+        assert tz_compare(result.tz, ts_tz.tz)
+
+    def test_sub_datetimelike_mismatched_reso(self, ts_tz):
+        # case with non-lossy rounding
+        ts = ts_tz
+
+        # choose a unit for `other` that doesn't match ts_tz's;
+        #  this construction ensures we get cases with other._creso < ts._creso
+        #  and cases with other._creso > ts._creso
+        unit = {
+            NpyDatetimeUnit.NPY_FR_us.value: "ms",
+            NpyDatetimeUnit.NPY_FR_ms.value: "s",
+            NpyDatetimeUnit.NPY_FR_s.value: "us",
+        }[ts._creso]
+        other = ts.as_unit(unit)
+        assert other._creso != ts._creso
+
+        result = ts - other
+        assert isinstance(result, Timedelta)
+        assert result._value == 0
+        assert result._creso == max(ts._creso, other._creso)
+
+        result = other - ts
+        assert isinstance(result, Timedelta)
+        assert result._value == 0
+        assert result._creso == max(ts._creso, other._creso)
+
+        if ts._creso < other._creso:
+            # Case where rounding is lossy
+            other2 = other + Timedelta._from_value_and_reso(1, other._creso)
+            exp = ts.as_unit(other.unit) - other2
+
+            res = ts - other2
+            assert res == exp
+            assert res._creso == max(ts._creso, other._creso)
+
+            res = other2 - ts
+            assert res == -exp
+            assert res._creso == max(ts._creso, other._creso)
+        else:
+            ts2 = ts + Timedelta._from_value_and_reso(1, ts._creso)
+            exp = ts2 - other.as_unit(ts2.unit)
+
+            res = ts2 - other
+            assert res == exp
+            assert res._creso == max(ts._creso, other._creso)
+            res = other - ts2
+            assert res == -exp
+            assert res._creso == max(ts._creso, other._creso)
+
+    def test_sub_timedeltalike_mismatched_reso(self, ts_tz):
+        # case with non-lossy rounding
+        ts = ts_tz
+
+        # choose a unit for `other` that doesn't match ts_tz's;
+        #  this construction ensures we get cases with other._creso < ts._creso
+        #  and cases with other._creso > ts._creso
+        unit = {
+            NpyDatetimeUnit.NPY_FR_us.value: "ms",
+            NpyDatetimeUnit.NPY_FR_ms.value: "s",
+            NpyDatetimeUnit.NPY_FR_s.value: "us",
+        }[ts._creso]
+        other = Timedelta(0).as_unit(unit)
+        assert other._creso != ts._creso
+
+        result = ts + other
+        assert isinstance(result, Timestamp)
+        assert result == ts
+        assert result._creso == max(ts._creso, other._creso)
+
+        result = other + ts
+        assert isinstance(result, Timestamp)
+        assert result == ts
+        assert result._creso == max(ts._creso, other._creso)
+
+        if ts._creso < other._creso:
+            # Case where rounding is lossy
+            other2 = other + Timedelta._from_value_and_reso(1, other._creso)
+            exp = ts.as_unit(other.unit) + other2
+            res = ts + other2
+            assert res == exp
+            assert res._creso == max(ts._creso, other._creso)
+            res = other2 + ts
+            assert res == exp
+            assert res._creso == max(ts._creso, other._creso)
+        else:
+            ts2 = ts + Timedelta._from_value_and_reso(1, ts._creso)
+            exp = ts2 + other.as_unit(ts2.unit)
+
+            res = ts2 + other
+            assert res == exp
+            assert res._creso == max(ts._creso, other._creso)
+            res = other + ts2
+            assert res == exp
+            assert res._creso == max(ts._creso, other._creso)
+
+    def test_addition_doesnt_downcast_reso(self):
+        # https://github.com/pandas-dev/pandas/pull/48748#pullrequestreview-1122635413
+        ts = Timestamp(year=2022, month=1, day=1, microsecond=999999).as_unit("us")
+        td = Timedelta(microseconds=1).as_unit("us")
+        res = ts + td
+        assert res._creso == ts._creso
+
+    def test_sub_timedelta64_mismatched_reso(self, ts_tz):
+        ts = ts_tz
+
+        res = ts + np.timedelta64(1, "ns")
+        exp = ts.as_unit("ns") + np.timedelta64(1, "ns")
+        assert exp == res
+        assert exp._creso == NpyDatetimeUnit.NPY_FR_ns.value
+
+    def test_min(self, ts):
+        assert ts.min <= ts
+        assert ts.min._creso == ts._creso
+        assert ts.min._value == NaT._value + 1
+
+    def test_max(self, ts):
+        assert ts.max >= ts
+        assert ts.max._creso == ts._creso
+        assert ts.max._value == np.iinfo(np.int64).max
+
+    def test_resolution(self, ts):
+        expected = Timedelta._from_value_and_reso(1, ts._creso)
+        result = ts.resolution
+        assert result == expected
+        assert result._creso == expected._creso
+
+    def test_out_of_ns_bounds(self):
+        # https://github.com/pandas-dev/pandas/issues/51060
+        result = Timestamp(-52700112000, unit="s")
+        assert result == Timestamp("0300-01-01")
+        assert result.to_numpy() == np.datetime64("0300-01-01T00:00:00", "s")
+
+
+def test_timestamp_class_min_max_resolution():
+    # when accessed on the class (as opposed to an instance), we default
+    #  to nanoseconds
+    assert Timestamp.min == Timestamp(NaT._value + 1)
+    assert Timestamp.min._creso == NpyDatetimeUnit.NPY_FR_ns.value
+
+    assert Timestamp.max == Timestamp(np.iinfo(np.int64).max)
+    assert Timestamp.max._creso == NpyDatetimeUnit.NPY_FR_ns.value
+
+    assert Timestamp.resolution == Timedelta(1)
+    assert Timestamp.resolution._creso == NpyDatetimeUnit.NPY_FR_ns.value
+
+
+def test_delimited_date():
+    # https://github.com/pandas-dev/pandas/issues/50231
+    with tm.assert_produces_warning(None):
+        result = Timestamp("13-01-2000")
+    expected = Timestamp(2000, 1, 13)
+    assert result == expected
+
+
+def test_utctimetuple():
+    # GH 32174
+    ts = Timestamp("2000-01-01", tz="UTC")
+    result = ts.utctimetuple()
+    expected = time.struct_time((2000, 1, 1, 0, 0, 0, 5, 1, 0))
+    assert result == expected
+
+
+def test_negative_dates():
+    # https://github.com/pandas-dev/pandas/issues/50787
+    ts = Timestamp("-2000-01-01")
+    msg = (
+        " not yet supported on Timestamps which are outside the range of "
+        "Python's standard library. For now, please call the components you need "
+        r"\(such as `.year` and `.month`\) and construct your string from there.$"
+    )
+    func = "^strftime"
+    with pytest.raises(NotImplementedError, match=func + msg):
+        ts.strftime("%Y")
+
+    msg = (
+        " not yet supported on Timestamps which "
+        "are outside the range of Python's standard library. "
+    )
+    func = "^date"
+    with pytest.raises(NotImplementedError, match=func + msg):
+        ts.date()
+    func = "^isocalendar"
+    with pytest.raises(NotImplementedError, match=func + msg):
+        ts.isocalendar()
+    func = "^timetuple"
+    with pytest.raises(NotImplementedError, match=func + msg):
+        ts.timetuple()
+    func = "^toordinal"
+    with pytest.raises(NotImplementedError, match=func + msg):
+        ts.toordinal()

lib/python3.11/site-packages/pandas/tests/scalar/timestamp/test_timezones.py

@@ -0,0 +1,24 @@
+"""
+Tests for Timestamp timezone-related methods
+"""
+from datetime import datetime
+
+from pandas._libs.tslibs import timezones
+
+from pandas import Timestamp
+
+
+class TestTimestampTZOperations:
+    # ------------------------------------------------------------------
+
+    def test_timestamp_timetz_equivalent_with_datetime_tz(self, tz_naive_fixture):
+        # GH21358
+        tz = timezones.maybe_get_tz(tz_naive_fixture)
+
+        stamp = Timestamp("2018-06-04 10:20:30", tz=tz)
+        _datetime = datetime(2018, 6, 4, hour=10, minute=20, second=30, tzinfo=tz)
+
+        result = stamp.timetz()
+        expected = _datetime.timetz()
+
+        assert result == expected