Updated script that can be controled by Nodejs web app

lib/python3.13/site-packages/pandas/tests/tseries/offsets/common.py

@@ -0,0 +1,37 @@
+"""
+Assertion helpers and base class for offsets tests
+"""
+from __future__ import annotations
+
+
+def assert_offset_equal(offset, base, expected):
+    actual = offset + base
+    actual_swapped = base + offset
+    actual_apply = offset._apply(base)
+    try:
+        assert actual == expected
+        assert actual_swapped == expected
+        assert actual_apply == expected
+    except AssertionError as err:
+        raise AssertionError(
+            f"\nExpected: {expected}\nActual: {actual}\nFor Offset: {offset})"
+            f"\nAt Date: {base}"
+        ) from err
+
+
+def assert_is_on_offset(offset, date, expected):
+    actual = offset.is_on_offset(date)
+    assert actual == expected, (
+        f"\nExpected: {expected}\nActual: {actual}\nFor Offset: {offset})"
+        f"\nAt Date: {date}"
+    )
+
+
+class WeekDay:
+    MON = 0
+    TUE = 1
+    WED = 2
+    THU = 3
+    FRI = 4
+    SAT = 5
+    SUN = 6

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_business_day.py

@@ -0,0 +1,236 @@
+"""
+Tests for offsets.BDay
+"""
+from __future__ import annotations
+
+from datetime import (
+    date,
+    datetime,
+    timedelta,
+)
+
+import numpy as np
+import pytest
+
+from pandas._libs.tslibs.offsets import (
+    ApplyTypeError,
+    BDay,
+    BMonthEnd,
+)
+
+from pandas import (
+    DatetimeIndex,
+    Timedelta,
+    _testing as tm,
+)
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries import offsets
+
+
+@pytest.fixture
+def dt():
+    return datetime(2008, 1, 1)
+
+
+@pytest.fixture
+def _offset():
+    return BDay
+
+
+@pytest.fixture
+def offset(_offset):
+    return _offset()
+
+
+@pytest.fixture
+def offset2(_offset):
+    return _offset(2)
+
+
+class TestBusinessDay:
+    def test_different_normalize_equals(self, _offset, offset2):
+        # GH#21404 changed __eq__ to return False when `normalize` does not match
+        offset = _offset()
+        offset2 = _offset(normalize=True)
+        assert offset != offset2
+
+    def test_repr(self, offset, offset2):
+        assert repr(offset) == "<BusinessDay>"
+        assert repr(offset2) == "<2 * BusinessDays>"
+
+        expected = "<BusinessDay: offset=datetime.timedelta(days=1)>"
+        assert repr(offset + timedelta(1)) == expected
+
+    def test_with_offset(self, dt, offset):
+        offset = offset + timedelta(hours=2)
+
+        assert (dt + offset) == datetime(2008, 1, 2, 2)
+
+    @pytest.mark.parametrize(
+        "td",
+        [
+            Timedelta(hours=2),
+            Timedelta(hours=2).to_pytimedelta(),
+            Timedelta(hours=2).to_timedelta64(),
+        ],
+        ids=lambda x: type(x),
+    )
+    def test_with_offset_index(self, td, dt, offset):
+        dti = DatetimeIndex([dt])
+        expected = DatetimeIndex([datetime(2008, 1, 2, 2)])
+
+        result = dti + (td + offset)
+        tm.assert_index_equal(result, expected)
+
+        result = dti + (offset + td)
+        tm.assert_index_equal(result, expected)
+
+    def test_eq(self, offset2):
+        assert offset2 == offset2
+
+    def test_hash(self, offset2):
+        assert hash(offset2) == hash(offset2)
+
+    def test_add_datetime(self, dt, offset2):
+        assert offset2 + dt == datetime(2008, 1, 3)
+        assert offset2 + np.datetime64("2008-01-01 00:00:00") == datetime(2008, 1, 3)
+
+    def testRollback1(self, dt, _offset):
+        assert _offset(10).rollback(dt) == dt
+
+    def testRollback2(self, _offset):
+        assert _offset(10).rollback(datetime(2008, 1, 5)) == datetime(2008, 1, 4)
+
+    def testRollforward1(self, dt, _offset):
+        assert _offset(10).rollforward(dt) == dt
+
+    def testRollforward2(self, _offset):
+        assert _offset(10).rollforward(datetime(2008, 1, 5)) == datetime(2008, 1, 7)
+
+    def test_roll_date_object(self, offset):
+        dt = date(2012, 9, 15)
+
+        result = offset.rollback(dt)
+        assert result == datetime(2012, 9, 14)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2012, 9, 17)
+
+        offset = offsets.Day()
+        result = offset.rollback(dt)
+        assert result == datetime(2012, 9, 15)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2012, 9, 15)
+
+    @pytest.mark.parametrize(
+        "dt, expected",
+        [
+            (datetime(2008, 1, 1), True),
+            (datetime(2008, 1, 5), False),
+        ],
+    )
+    def test_is_on_offset(self, offset, dt, expected):
+        assert_is_on_offset(offset, dt, expected)
+
+    apply_cases: list[tuple[int, dict[datetime, datetime]]] = [
+        (
+            1,
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 2),
+                datetime(2008, 1, 4): datetime(2008, 1, 7),
+                datetime(2008, 1, 5): datetime(2008, 1, 7),
+                datetime(2008, 1, 6): datetime(2008, 1, 7),
+                datetime(2008, 1, 7): datetime(2008, 1, 8),
+            },
+        ),
+        (
+            2,
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 3),
+                datetime(2008, 1, 4): datetime(2008, 1, 8),
+                datetime(2008, 1, 5): datetime(2008, 1, 8),
+                datetime(2008, 1, 6): datetime(2008, 1, 8),
+                datetime(2008, 1, 7): datetime(2008, 1, 9),
+            },
+        ),
+        (
+            -1,
+            {
+                datetime(2008, 1, 1): datetime(2007, 12, 31),
+                datetime(2008, 1, 4): datetime(2008, 1, 3),
+                datetime(2008, 1, 5): datetime(2008, 1, 4),
+                datetime(2008, 1, 6): datetime(2008, 1, 4),
+                datetime(2008, 1, 7): datetime(2008, 1, 4),
+                datetime(2008, 1, 8): datetime(2008, 1, 7),
+            },
+        ),
+        (
+            -2,
+            {
+                datetime(2008, 1, 1): datetime(2007, 12, 28),
+                datetime(2008, 1, 4): datetime(2008, 1, 2),
+                datetime(2008, 1, 5): datetime(2008, 1, 3),
+                datetime(2008, 1, 6): datetime(2008, 1, 3),
+                datetime(2008, 1, 7): datetime(2008, 1, 3),
+                datetime(2008, 1, 8): datetime(2008, 1, 4),
+                datetime(2008, 1, 9): datetime(2008, 1, 7),
+            },
+        ),
+        (
+            0,
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 1, 4): datetime(2008, 1, 4),
+                datetime(2008, 1, 5): datetime(2008, 1, 7),
+                datetime(2008, 1, 6): datetime(2008, 1, 7),
+                datetime(2008, 1, 7): datetime(2008, 1, 7),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("case", apply_cases)
+    def test_apply(self, case, _offset):
+        n, cases = case
+        offset = _offset(n)
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    def test_apply_large_n(self, _offset):
+        dt = datetime(2012, 10, 23)
+
+        result = dt + _offset(10)
+        assert result == datetime(2012, 11, 6)
+
+        result = dt + _offset(100) - _offset(100)
+        assert result == dt
+
+        off = _offset() * 6
+        rs = datetime(2012, 1, 1) - off
+        xp = datetime(2011, 12, 23)
+        assert rs == xp
+
+        st = datetime(2011, 12, 18)
+        rs = st + off
+        xp = datetime(2011, 12, 26)
+        assert rs == xp
+
+        off = _offset() * 10
+        rs = datetime(2014, 1, 5) + off  # see #5890
+        xp = datetime(2014, 1, 17)
+        assert rs == xp
+
+    def test_apply_corner(self, _offset):
+        if _offset is BDay:
+            msg = "Only know how to combine business day with datetime or timedelta"
+        else:
+            msg = (
+                "Only know how to combine trading day "
+                "with datetime, datetime64 or timedelta"
+            )
+        with pytest.raises(ApplyTypeError, match=msg):
+            _offset()._apply(BMonthEnd())

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_business_month.py

@@ -0,0 +1,217 @@
+"""
+Tests for the following offsets:
+- BMonthBegin
+- BMonthEnd
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+
+import pandas as pd
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries.offsets import (
+    BMonthBegin,
+    BMonthEnd,
+)
+
+
+@pytest.mark.parametrize("n", [-2, 1])
+@pytest.mark.parametrize(
+    "cls",
+    [
+        BMonthBegin,
+        BMonthEnd,
+    ],
+)
+def test_apply_index(cls, n):
+    offset = cls(n=n)
+    rng = pd.date_range(start="1/1/2000", periods=100000, freq="min")
+    ser = pd.Series(rng)
+
+    res = rng + offset
+    assert res.freq is None  # not retained
+    assert res[0] == rng[0] + offset
+    assert res[-1] == rng[-1] + offset
+    res2 = ser + offset
+    # apply_index is only for indexes, not series, so no res2_v2
+    assert res2.iloc[0] == ser.iloc[0] + offset
+    assert res2.iloc[-1] == ser.iloc[-1] + offset
+
+
+class TestBMonthBegin:
+    def test_offsets_compare_equal(self):
+        # root cause of #456
+        offset1 = BMonthBegin()
+        offset2 = BMonthBegin()
+        assert not offset1 != offset2
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            BMonthBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 1),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2006, 12, 29): datetime(2007, 1, 1),
+                datetime(2006, 12, 31): datetime(2007, 1, 1),
+                datetime(2006, 9, 1): datetime(2006, 10, 2),
+                datetime(2007, 1, 1): datetime(2007, 2, 1),
+                datetime(2006, 12, 1): datetime(2007, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BMonthBegin(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2006, 10, 2): datetime(2006, 10, 2),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2006, 12, 29): datetime(2007, 1, 1),
+                datetime(2006, 12, 31): datetime(2007, 1, 1),
+                datetime(2006, 9, 15): datetime(2006, 10, 2),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BMonthBegin(2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 3, 3),
+                datetime(2008, 1, 15): datetime(2008, 3, 3),
+                datetime(2006, 12, 29): datetime(2007, 2, 1),
+                datetime(2006, 12, 31): datetime(2007, 2, 1),
+                datetime(2007, 1, 1): datetime(2007, 3, 1),
+                datetime(2006, 11, 1): datetime(2007, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BMonthBegin(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 1),
+                datetime(2008, 6, 30): datetime(2008, 6, 2),
+                datetime(2008, 6, 1): datetime(2008, 5, 1),
+                datetime(2008, 3, 10): datetime(2008, 3, 3),
+                datetime(2008, 12, 31): datetime(2008, 12, 1),
+                datetime(2006, 12, 29): datetime(2006, 12, 1),
+                datetime(2006, 12, 30): datetime(2006, 12, 1),
+                datetime(2007, 1, 1): datetime(2006, 12, 1),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (BMonthBegin(), datetime(2007, 12, 31), False),
+        (BMonthBegin(), datetime(2008, 1, 1), True),
+        (BMonthBegin(), datetime(2001, 4, 2), True),
+        (BMonthBegin(), datetime(2008, 3, 3), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+
+class TestBMonthEnd:
+    def test_normalize(self):
+        dt = datetime(2007, 1, 1, 3)
+
+        result = dt + BMonthEnd(normalize=True)
+        expected = dt.replace(hour=0) + BMonthEnd()
+        assert result == expected
+
+    def test_offsets_compare_equal(self):
+        # root cause of #456
+        offset1 = BMonthEnd()
+        offset2 = BMonthEnd()
+        assert not offset1 != offset2
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            BMonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 2, 29),
+                datetime(2006, 12, 29): datetime(2007, 1, 31),
+                datetime(2006, 12, 31): datetime(2007, 1, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 31),
+                datetime(2006, 12, 1): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BMonthEnd(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 1, 31),
+                datetime(2006, 12, 29): datetime(2006, 12, 29),
+                datetime(2006, 12, 31): datetime(2007, 1, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BMonthEnd(2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 29),
+                datetime(2008, 1, 31): datetime(2008, 3, 31),
+                datetime(2006, 12, 29): datetime(2007, 2, 28),
+                datetime(2006, 12, 31): datetime(2007, 2, 28),
+                datetime(2007, 1, 1): datetime(2007, 2, 28),
+                datetime(2006, 11, 1): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BMonthEnd(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 29),
+                datetime(2008, 6, 30): datetime(2008, 5, 30),
+                datetime(2008, 12, 31): datetime(2008, 11, 28),
+                datetime(2006, 12, 29): datetime(2006, 11, 30),
+                datetime(2006, 12, 30): datetime(2006, 12, 29),
+                datetime(2007, 1, 1): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (BMonthEnd(), datetime(2007, 12, 31), True),
+        (BMonthEnd(), datetime(2008, 1, 1), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_business_quarter.py

@@ -0,0 +1,315 @@
+"""
+Tests for the following offsets:
+- BQuarterBegin
+- BQuarterEnd
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+
+import pandas._testing as tm
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries.offsets import (
+    BQuarterBegin,
+    BQuarterEnd,
+)
+
+
+def test_quarterly_dont_normalize():
+    date = datetime(2012, 3, 31, 5, 30)
+
+    offsets = (BQuarterEnd, BQuarterBegin)
+
+    for klass in offsets:
+        result = date + klass()
+        assert result.time() == date.time()
+
+
+@pytest.mark.parametrize("offset", [BQuarterBegin(), BQuarterEnd()])
+def test_on_offset(offset):
+    dates = [
+        datetime(2016, m, d)
+        for m in [10, 11, 12]
+        for d in [1, 2, 3, 28, 29, 30, 31]
+        if not (m == 11 and d == 31)
+    ]
+    for date in dates:
+        res = offset.is_on_offset(date)
+        slow_version = date == (date + offset) - offset
+        assert res == slow_version
+
+
+class TestBQuarterBegin:
+    def test_repr(self):
+        expected = "<BusinessQuarterBegin: startingMonth=3>"
+        assert repr(BQuarterBegin()) == expected
+        expected = "<BusinessQuarterBegin: startingMonth=3>"
+        assert repr(BQuarterBegin(startingMonth=3)) == expected
+        expected = "<BusinessQuarterBegin: startingMonth=1>"
+        assert repr(BQuarterBegin(startingMonth=1)) == expected
+
+    def test_is_anchored(self):
+        msg = "BQuarterBegin.is_anchored is deprecated "
+
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            assert BQuarterBegin(startingMonth=1).is_anchored()
+            assert BQuarterBegin().is_anchored()
+            assert not BQuarterBegin(2, startingMonth=1).is_anchored()
+
+    def test_offset_corner_case(self):
+        # corner
+        offset = BQuarterBegin(n=-1, startingMonth=1)
+        assert datetime(2007, 4, 3) + offset == datetime(2007, 4, 2)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            BQuarterBegin(startingMonth=1),
+            {
+                datetime(2008, 1, 1): datetime(2008, 4, 1),
+                datetime(2008, 1, 31): datetime(2008, 4, 1),
+                datetime(2008, 2, 15): datetime(2008, 4, 1),
+                datetime(2008, 2, 29): datetime(2008, 4, 1),
+                datetime(2008, 3, 15): datetime(2008, 4, 1),
+                datetime(2008, 3, 31): datetime(2008, 4, 1),
+                datetime(2008, 4, 15): datetime(2008, 7, 1),
+                datetime(2007, 3, 15): datetime(2007, 4, 2),
+                datetime(2007, 2, 28): datetime(2007, 4, 2),
+                datetime(2007, 1, 1): datetime(2007, 4, 2),
+                datetime(2007, 4, 15): datetime(2007, 7, 2),
+                datetime(2007, 7, 1): datetime(2007, 7, 2),
+                datetime(2007, 4, 1): datetime(2007, 4, 2),
+                datetime(2007, 4, 2): datetime(2007, 7, 2),
+                datetime(2008, 4, 30): datetime(2008, 7, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterBegin(startingMonth=2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 1),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2008, 1, 15): datetime(2008, 2, 1),
+                datetime(2008, 2, 29): datetime(2008, 5, 1),
+                datetime(2008, 3, 15): datetime(2008, 5, 1),
+                datetime(2008, 3, 31): datetime(2008, 5, 1),
+                datetime(2008, 4, 15): datetime(2008, 5, 1),
+                datetime(2008, 8, 15): datetime(2008, 11, 3),
+                datetime(2008, 9, 15): datetime(2008, 11, 3),
+                datetime(2008, 11, 1): datetime(2008, 11, 3),
+                datetime(2008, 4, 30): datetime(2008, 5, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterBegin(startingMonth=1, n=0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2007, 12, 31): datetime(2008, 1, 1),
+                datetime(2008, 2, 15): datetime(2008, 4, 1),
+                datetime(2008, 2, 29): datetime(2008, 4, 1),
+                datetime(2008, 1, 15): datetime(2008, 4, 1),
+                datetime(2008, 2, 27): datetime(2008, 4, 1),
+                datetime(2008, 3, 15): datetime(2008, 4, 1),
+                datetime(2007, 4, 1): datetime(2007, 4, 2),
+                datetime(2007, 4, 2): datetime(2007, 4, 2),
+                datetime(2007, 7, 1): datetime(2007, 7, 2),
+                datetime(2007, 4, 15): datetime(2007, 7, 2),
+                datetime(2007, 7, 2): datetime(2007, 7, 2),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterBegin(startingMonth=1, n=-1),
+            {
+                datetime(2008, 1, 1): datetime(2007, 10, 1),
+                datetime(2008, 1, 31): datetime(2008, 1, 1),
+                datetime(2008, 2, 15): datetime(2008, 1, 1),
+                datetime(2008, 2, 29): datetime(2008, 1, 1),
+                datetime(2008, 3, 15): datetime(2008, 1, 1),
+                datetime(2008, 3, 31): datetime(2008, 1, 1),
+                datetime(2008, 4, 15): datetime(2008, 4, 1),
+                datetime(2007, 7, 3): datetime(2007, 7, 2),
+                datetime(2007, 4, 3): datetime(2007, 4, 2),
+                datetime(2007, 7, 2): datetime(2007, 4, 2),
+                datetime(2008, 4, 1): datetime(2008, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterBegin(startingMonth=1, n=2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 7, 1),
+                datetime(2008, 1, 15): datetime(2008, 7, 1),
+                datetime(2008, 2, 29): datetime(2008, 7, 1),
+                datetime(2008, 3, 15): datetime(2008, 7, 1),
+                datetime(2007, 3, 31): datetime(2007, 7, 2),
+                datetime(2007, 4, 15): datetime(2007, 10, 1),
+                datetime(2008, 4, 30): datetime(2008, 10, 1),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+
+class TestBQuarterEnd:
+    def test_repr(self):
+        expected = "<BusinessQuarterEnd: startingMonth=3>"
+        assert repr(BQuarterEnd()) == expected
+        expected = "<BusinessQuarterEnd: startingMonth=3>"
+        assert repr(BQuarterEnd(startingMonth=3)) == expected
+        expected = "<BusinessQuarterEnd: startingMonth=1>"
+        assert repr(BQuarterEnd(startingMonth=1)) == expected
+
+    def test_is_anchored(self):
+        msg = "BQuarterEnd.is_anchored is deprecated "
+
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            assert BQuarterEnd(startingMonth=1).is_anchored()
+            assert BQuarterEnd().is_anchored()
+            assert not BQuarterEnd(2, startingMonth=1).is_anchored()
+
+    def test_offset_corner_case(self):
+        # corner
+        offset = BQuarterEnd(n=-1, startingMonth=1)
+        assert datetime(2010, 1, 31) + offset == datetime(2010, 1, 29)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            BQuarterEnd(startingMonth=1),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 4, 30),
+                datetime(2008, 2, 15): datetime(2008, 4, 30),
+                datetime(2008, 2, 29): datetime(2008, 4, 30),
+                datetime(2008, 3, 15): datetime(2008, 4, 30),
+                datetime(2008, 3, 31): datetime(2008, 4, 30),
+                datetime(2008, 4, 15): datetime(2008, 4, 30),
+                datetime(2008, 4, 30): datetime(2008, 7, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterEnd(startingMonth=2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 29),
+                datetime(2008, 1, 31): datetime(2008, 2, 29),
+                datetime(2008, 2, 15): datetime(2008, 2, 29),
+                datetime(2008, 2, 29): datetime(2008, 5, 30),
+                datetime(2008, 3, 15): datetime(2008, 5, 30),
+                datetime(2008, 3, 31): datetime(2008, 5, 30),
+                datetime(2008, 4, 15): datetime(2008, 5, 30),
+                datetime(2008, 4, 30): datetime(2008, 5, 30),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterEnd(startingMonth=1, n=0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 1, 31),
+                datetime(2008, 2, 15): datetime(2008, 4, 30),
+                datetime(2008, 2, 29): datetime(2008, 4, 30),
+                datetime(2008, 3, 15): datetime(2008, 4, 30),
+                datetime(2008, 3, 31): datetime(2008, 4, 30),
+                datetime(2008, 4, 15): datetime(2008, 4, 30),
+                datetime(2008, 4, 30): datetime(2008, 4, 30),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterEnd(startingMonth=1, n=-1),
+            {
+                datetime(2008, 1, 1): datetime(2007, 10, 31),
+                datetime(2008, 1, 31): datetime(2007, 10, 31),
+                datetime(2008, 2, 15): datetime(2008, 1, 31),
+                datetime(2008, 2, 29): datetime(2008, 1, 31),
+                datetime(2008, 3, 15): datetime(2008, 1, 31),
+                datetime(2008, 3, 31): datetime(2008, 1, 31),
+                datetime(2008, 4, 15): datetime(2008, 1, 31),
+                datetime(2008, 4, 30): datetime(2008, 1, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BQuarterEnd(startingMonth=1, n=2),
+            {
+                datetime(2008, 1, 31): datetime(2008, 7, 31),
+                datetime(2008, 2, 15): datetime(2008, 7, 31),
+                datetime(2008, 2, 29): datetime(2008, 7, 31),
+                datetime(2008, 3, 15): datetime(2008, 7, 31),
+                datetime(2008, 3, 31): datetime(2008, 7, 31),
+                datetime(2008, 4, 15): datetime(2008, 7, 31),
+                datetime(2008, 4, 30): datetime(2008, 10, 31),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (BQuarterEnd(1, startingMonth=1), datetime(2008, 1, 31), True),
+        (BQuarterEnd(1, startingMonth=1), datetime(2007, 12, 31), False),
+        (BQuarterEnd(1, startingMonth=1), datetime(2008, 2, 29), False),
+        (BQuarterEnd(1, startingMonth=1), datetime(2007, 3, 30), False),
+        (BQuarterEnd(1, startingMonth=1), datetime(2007, 3, 31), False),
+        (BQuarterEnd(1, startingMonth=1), datetime(2008, 4, 30), True),
+        (BQuarterEnd(1, startingMonth=1), datetime(2008, 5, 30), False),
+        (BQuarterEnd(1, startingMonth=1), datetime(2007, 6, 29), False),
+        (BQuarterEnd(1, startingMonth=1), datetime(2007, 6, 30), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2008, 1, 31), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2007, 12, 31), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2008, 2, 29), True),
+        (BQuarterEnd(1, startingMonth=2), datetime(2007, 3, 30), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2007, 3, 31), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2008, 4, 30), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2008, 5, 30), True),
+        (BQuarterEnd(1, startingMonth=2), datetime(2007, 6, 29), False),
+        (BQuarterEnd(1, startingMonth=2), datetime(2007, 6, 30), False),
+        (BQuarterEnd(1, startingMonth=3), datetime(2008, 1, 31), False),
+        (BQuarterEnd(1, startingMonth=3), datetime(2007, 12, 31), True),
+        (BQuarterEnd(1, startingMonth=3), datetime(2008, 2, 29), False),
+        (BQuarterEnd(1, startingMonth=3), datetime(2007, 3, 30), True),
+        (BQuarterEnd(1, startingMonth=3), datetime(2007, 3, 31), False),
+        (BQuarterEnd(1, startingMonth=3), datetime(2008, 4, 30), False),
+        (BQuarterEnd(1, startingMonth=3), datetime(2008, 5, 30), False),
+        (BQuarterEnd(1, startingMonth=3), datetime(2007, 6, 29), True),
+        (BQuarterEnd(1, startingMonth=3), datetime(2007, 6, 30), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_business_year.py

@@ -0,0 +1,215 @@
+"""
+Tests for the following offsets:
+- BYearBegin
+- BYearEnd
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries.offsets import (
+    BYearBegin,
+    BYearEnd,
+)
+
+
+class TestBYearBegin:
+    def test_misspecified(self):
+        msg = "Month must go from 1 to 12"
+        with pytest.raises(ValueError, match=msg):
+            BYearBegin(month=13)
+        with pytest.raises(ValueError, match=msg):
+            BYearEnd(month=13)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            BYearBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2009, 1, 1),
+                datetime(2008, 6, 30): datetime(2009, 1, 1),
+                datetime(2008, 12, 31): datetime(2009, 1, 1),
+                datetime(2011, 1, 1): datetime(2011, 1, 3),
+                datetime(2011, 1, 3): datetime(2012, 1, 2),
+                datetime(2005, 12, 30): datetime(2006, 1, 2),
+                datetime(2005, 12, 31): datetime(2006, 1, 2),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearBegin(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 6, 30): datetime(2009, 1, 1),
+                datetime(2008, 12, 31): datetime(2009, 1, 1),
+                datetime(2005, 12, 30): datetime(2006, 1, 2),
+                datetime(2005, 12, 31): datetime(2006, 1, 2),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearBegin(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 1, 2),
+                datetime(2009, 1, 4): datetime(2009, 1, 1),
+                datetime(2009, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 6, 30): datetime(2008, 1, 1),
+                datetime(2008, 12, 31): datetime(2008, 1, 1),
+                datetime(2006, 12, 29): datetime(2006, 1, 2),
+                datetime(2006, 12, 30): datetime(2006, 1, 2),
+                datetime(2006, 1, 1): datetime(2005, 1, 3),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearBegin(-2),
+            {
+                datetime(2007, 1, 1): datetime(2005, 1, 3),
+                datetime(2007, 6, 30): datetime(2006, 1, 2),
+                datetime(2008, 12, 31): datetime(2007, 1, 1),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+
+class TestBYearEnd:
+    offset_cases = []
+    offset_cases.append(
+        (
+            BYearEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 12, 31),
+                datetime(2008, 12, 31): datetime(2009, 12, 31),
+                datetime(2005, 12, 30): datetime(2006, 12, 29),
+                datetime(2005, 12, 31): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearEnd(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 12, 31),
+                datetime(2008, 12, 31): datetime(2008, 12, 31),
+                datetime(2005, 12, 31): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearEnd(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 29),
+                datetime(2008, 6, 30): datetime(2007, 12, 31),
+                datetime(2008, 12, 31): datetime(2007, 12, 31),
+                datetime(2006, 12, 29): datetime(2005, 12, 30),
+                datetime(2006, 12, 30): datetime(2006, 12, 29),
+                datetime(2007, 1, 1): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearEnd(-2),
+            {
+                datetime(2007, 1, 1): datetime(2005, 12, 30),
+                datetime(2008, 6, 30): datetime(2006, 12, 29),
+                datetime(2008, 12, 31): datetime(2006, 12, 29),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (BYearEnd(), datetime(2007, 12, 31), True),
+        (BYearEnd(), datetime(2008, 1, 1), False),
+        (BYearEnd(), datetime(2006, 12, 31), False),
+        (BYearEnd(), datetime(2006, 12, 29), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+
+class TestBYearEndLagged:
+    def test_bad_month_fail(self):
+        msg = "Month must go from 1 to 12"
+        with pytest.raises(ValueError, match=msg):
+            BYearEnd(month=13)
+        with pytest.raises(ValueError, match=msg):
+            BYearEnd(month=0)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            BYearEnd(month=6),
+            {
+                datetime(2008, 1, 1): datetime(2008, 6, 30),
+                datetime(2007, 6, 30): datetime(2008, 6, 30),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            BYearEnd(n=-1, month=6),
+            {
+                datetime(2008, 1, 1): datetime(2007, 6, 29),
+                datetime(2007, 6, 30): datetime(2007, 6, 29),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    def test_roll(self):
+        offset = BYearEnd(month=6)
+        date = datetime(2009, 11, 30)
+
+        assert offset.rollforward(date) == datetime(2010, 6, 30)
+        assert offset.rollback(date) == datetime(2009, 6, 30)
+
+    on_offset_cases = [
+        (BYearEnd(month=2), datetime(2007, 2, 28), True),
+        (BYearEnd(month=6), datetime(2007, 6, 30), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_common.py

@@ -0,0 +1,268 @@
+from datetime import datetime
+
+from dateutil.tz.tz import tzlocal
+import pytest
+
+from pandas._libs.tslibs import (
+    OutOfBoundsDatetime,
+    Timestamp,
+)
+from pandas.compat import (
+    IS64,
+    is_platform_windows,
+)
+
+from pandas.tseries.offsets import (
+    FY5253,
+    BDay,
+    BMonthBegin,
+    BMonthEnd,
+    BQuarterBegin,
+    BQuarterEnd,
+    BusinessHour,
+    BYearBegin,
+    BYearEnd,
+    CBMonthBegin,
+    CBMonthEnd,
+    CDay,
+    CustomBusinessHour,
+    DateOffset,
+    FY5253Quarter,
+    LastWeekOfMonth,
+    MonthBegin,
+    MonthEnd,
+    QuarterEnd,
+    SemiMonthBegin,
+    SemiMonthEnd,
+    Week,
+    WeekOfMonth,
+    YearBegin,
+    YearEnd,
+)
+
+
+def _get_offset(klass, value=1, normalize=False):
+    # create instance from offset class
+    if klass is FY5253:
+        klass = klass(
+            n=value,
+            startingMonth=1,
+            weekday=1,
+            variation="last",
+            normalize=normalize,
+        )
+    elif klass is FY5253Quarter:
+        klass = klass(
+            n=value,
+            startingMonth=1,
+            weekday=1,
+            qtr_with_extra_week=1,
+            variation="last",
+            normalize=normalize,
+        )
+    elif klass is LastWeekOfMonth:
+        klass = klass(n=value, weekday=5, normalize=normalize)
+    elif klass is WeekOfMonth:
+        klass = klass(n=value, week=1, weekday=5, normalize=normalize)
+    elif klass is Week:
+        klass = klass(n=value, weekday=5, normalize=normalize)
+    elif klass is DateOffset:
+        klass = klass(days=value, normalize=normalize)
+    else:
+        klass = klass(value, normalize=normalize)
+    return klass
+
+
+@pytest.fixture(
+    params=[
+        BDay,
+        BusinessHour,
+        BMonthEnd,
+        BMonthBegin,
+        BQuarterEnd,
+        BQuarterBegin,
+        BYearEnd,
+        BYearBegin,
+        CDay,
+        CustomBusinessHour,
+        CBMonthEnd,
+        CBMonthBegin,
+        MonthEnd,
+        MonthBegin,
+        SemiMonthBegin,
+        SemiMonthEnd,
+        QuarterEnd,
+        LastWeekOfMonth,
+        WeekOfMonth,
+        Week,
+        YearBegin,
+        YearEnd,
+        FY5253,
+        FY5253Quarter,
+        DateOffset,
+    ]
+)
+def _offset(request):
+    return request.param
+
+
+@pytest.fixture
+def dt(_offset):
+    if _offset in (CBMonthBegin, CBMonthEnd, BDay):
+        return Timestamp(2008, 1, 1)
+    elif _offset is (CustomBusinessHour, BusinessHour):
+        return Timestamp(2014, 7, 1, 10, 00)
+    return Timestamp(2008, 1, 2)
+
+
+def test_apply_out_of_range(request, tz_naive_fixture, _offset):
+    tz = tz_naive_fixture
+
+    # try to create an out-of-bounds result timestamp; if we can't create
+    # the offset skip
+    try:
+        if _offset in (BusinessHour, CustomBusinessHour):
+            # Using 10000 in BusinessHour fails in tz check because of DST
+            # difference
+            offset = _get_offset(_offset, value=100000)
+        else:
+            offset = _get_offset(_offset, value=10000)
+
+        result = Timestamp("20080101") + offset
+        assert isinstance(result, datetime)
+        assert result.tzinfo is None
+
+        # Check tz is preserved
+        t = Timestamp("20080101", tz=tz)
+        result = t + offset
+        assert isinstance(result, datetime)
+        if tz is not None:
+            assert t.tzinfo is not None
+
+        if isinstance(tz, tzlocal) and not IS64 and _offset is not DateOffset:
+            # If we hit OutOfBoundsDatetime on non-64 bit machines
+            # we'll drop out of the try clause before the next test
+            request.applymarker(
+                pytest.mark.xfail(reason="OverflowError inside tzlocal past 2038")
+            )
+        elif (
+            isinstance(tz, tzlocal)
+            and is_platform_windows()
+            and _offset in (QuarterEnd, BQuarterBegin, BQuarterEnd)
+        ):
+            request.applymarker(
+                pytest.mark.xfail(reason="After GH#49737 t.tzinfo is None on CI")
+            )
+        assert str(t.tzinfo) == str(result.tzinfo)
+
+    except OutOfBoundsDatetime:
+        pass
+    except (ValueError, KeyError):
+        # we are creating an invalid offset
+        # so ignore
+        pass
+
+
+def test_offsets_compare_equal(_offset):
+    # root cause of GH#456: __ne__ was not implemented
+    offset1 = _offset()
+    offset2 = _offset()
+    assert not offset1 != offset2
+    assert offset1 == offset2
+
+
+@pytest.mark.parametrize(
+    "date, offset2",
+    [
+        [Timestamp(2008, 1, 1), BDay(2)],
+        [Timestamp(2014, 7, 1, 10, 00), BusinessHour(n=3)],
+        [
+            Timestamp(2014, 7, 1, 10),
+            CustomBusinessHour(
+                holidays=["2014-06-27", Timestamp(2014, 6, 30), Timestamp("2014-07-02")]
+            ),
+        ],
+        [Timestamp(2008, 1, 2), SemiMonthEnd(2)],
+        [Timestamp(2008, 1, 2), SemiMonthBegin(2)],
+        [Timestamp(2008, 1, 2), Week(2)],
+        [Timestamp(2008, 1, 2), WeekOfMonth(2)],
+        [Timestamp(2008, 1, 2), LastWeekOfMonth(2)],
+    ],
+)
+def test_rsub(date, offset2):
+    assert date - offset2 == (-offset2)._apply(date)
+
+
+@pytest.mark.parametrize(
+    "date, offset2",
+    [
+        [Timestamp(2008, 1, 1), BDay(2)],
+        [Timestamp(2014, 7, 1, 10, 00), BusinessHour(n=3)],
+        [
+            Timestamp(2014, 7, 1, 10),
+            CustomBusinessHour(
+                holidays=["2014-06-27", Timestamp(2014, 6, 30), Timestamp("2014-07-02")]
+            ),
+        ],
+        [Timestamp(2008, 1, 2), SemiMonthEnd(2)],
+        [Timestamp(2008, 1, 2), SemiMonthBegin(2)],
+        [Timestamp(2008, 1, 2), Week(2)],
+        [Timestamp(2008, 1, 2), WeekOfMonth(2)],
+        [Timestamp(2008, 1, 2), LastWeekOfMonth(2)],
+    ],
+)
+def test_radd(date, offset2):
+    assert date + offset2 == offset2 + date
+
+
+@pytest.mark.parametrize(
+    "date, offset_box, offset2",
+    [
+        [Timestamp(2008, 1, 1), BDay, BDay(2)],
+        [Timestamp(2008, 1, 2), SemiMonthEnd, SemiMonthEnd(2)],
+        [Timestamp(2008, 1, 2), SemiMonthBegin, SemiMonthBegin(2)],
+        [Timestamp(2008, 1, 2), Week, Week(2)],
+        [Timestamp(2008, 1, 2), WeekOfMonth, WeekOfMonth(2)],
+        [Timestamp(2008, 1, 2), LastWeekOfMonth, LastWeekOfMonth(2)],
+    ],
+)
+def test_sub(date, offset_box, offset2):
+    off = offset2
+    msg = "Cannot subtract datetime from offset"
+    with pytest.raises(TypeError, match=msg):
+        off - date
+
+    assert 2 * off - off == off
+    assert date - offset2 == date + offset_box(-2)
+    assert date - offset2 == date - (2 * off - off)
+
+
+@pytest.mark.parametrize(
+    "offset_box, offset1",
+    [
+        [BDay, BDay()],
+        [LastWeekOfMonth, LastWeekOfMonth()],
+        [WeekOfMonth, WeekOfMonth()],
+        [Week, Week()],
+        [SemiMonthBegin, SemiMonthBegin()],
+        [SemiMonthEnd, SemiMonthEnd()],
+        [CustomBusinessHour, CustomBusinessHour(weekmask="Tue Wed Thu Fri")],
+        [BusinessHour, BusinessHour()],
+    ],
+)
+def test_Mult1(offset_box, offset1):
+    dt = Timestamp(2008, 1, 2)
+    assert dt + 10 * offset1 == dt + offset_box(10)
+    assert dt + 5 * offset1 == dt + offset_box(5)
+
+
+def test_compare_str(_offset):
+    # GH#23524
+    # comparing to strings that cannot be cast to DateOffsets should
+    #  not raise for __eq__ or __ne__
+    off = _get_offset(_offset)
+
+    assert not off == "infer"
+    assert off != "foo"
+    # Note: inequalities are only implemented for Tick subclasses;
+    #  tests for this are in test_ticks

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_custom_business_day.py

@@ -0,0 +1,98 @@
+"""
+Tests for offsets.CustomBusinessDay / CDay
+"""
+from datetime import (
+    datetime,
+    timedelta,
+)
+
+import numpy as np
+import pytest
+
+from pandas._libs.tslibs.offsets import CDay
+
+from pandas import (
+    _testing as tm,
+    read_pickle,
+)
+from pandas.tests.tseries.offsets.common import assert_offset_equal
+
+from pandas.tseries.holiday import USFederalHolidayCalendar
+
+
+@pytest.fixture
+def offset():
+    return CDay()
+
+
+@pytest.fixture
+def offset2():
+    return CDay(2)
+
+
+class TestCustomBusinessDay:
+    def test_repr(self, offset, offset2):
+        assert repr(offset) == "<CustomBusinessDay>"
+        assert repr(offset2) == "<2 * CustomBusinessDays>"
+
+        expected = "<BusinessDay: offset=datetime.timedelta(days=1)>"
+        assert repr(offset + timedelta(1)) == expected
+
+    def test_holidays(self):
+        # Define a TradingDay offset
+        holidays = ["2012-05-01", datetime(2013, 5, 1), np.datetime64("2014-05-01")]
+        tday = CDay(holidays=holidays)
+        for year in range(2012, 2015):
+            dt = datetime(year, 4, 30)
+            xp = datetime(year, 5, 2)
+            rs = dt + tday
+            assert rs == xp
+
+    def test_weekmask(self):
+        weekmask_saudi = "Sat Sun Mon Tue Wed"  # Thu-Fri Weekend
+        weekmask_uae = "1111001"  # Fri-Sat Weekend
+        weekmask_egypt = [1, 1, 1, 1, 0, 0, 1]  # Fri-Sat Weekend
+        bday_saudi = CDay(weekmask=weekmask_saudi)
+        bday_uae = CDay(weekmask=weekmask_uae)
+        bday_egypt = CDay(weekmask=weekmask_egypt)
+        dt = datetime(2013, 5, 1)
+        xp_saudi = datetime(2013, 5, 4)
+        xp_uae = datetime(2013, 5, 2)
+        xp_egypt = datetime(2013, 5, 2)
+        assert xp_saudi == dt + bday_saudi
+        assert xp_uae == dt + bday_uae
+        assert xp_egypt == dt + bday_egypt
+        xp2 = datetime(2013, 5, 5)
+        assert xp2 == dt + 2 * bday_saudi
+        assert xp2 == dt + 2 * bday_uae
+        assert xp2 == dt + 2 * bday_egypt
+
+    def test_weekmask_and_holidays(self):
+        weekmask_egypt = "Sun Mon Tue Wed Thu"  # Fri-Sat Weekend
+        holidays = ["2012-05-01", datetime(2013, 5, 1), np.datetime64("2014-05-01")]
+        bday_egypt = CDay(holidays=holidays, weekmask=weekmask_egypt)
+        dt = datetime(2013, 4, 30)
+        xp_egypt = datetime(2013, 5, 5)
+        assert xp_egypt == dt + 2 * bday_egypt
+
+    @pytest.mark.filterwarnings("ignore:Non:pandas.errors.PerformanceWarning")
+    def test_calendar(self):
+        calendar = USFederalHolidayCalendar()
+        dt = datetime(2014, 1, 17)
+        assert_offset_equal(CDay(calendar=calendar), dt, datetime(2014, 1, 21))
+
+    def test_roundtrip_pickle(self, offset, offset2):
+        def _check_roundtrip(obj):
+            unpickled = tm.round_trip_pickle(obj)
+            assert unpickled == obj
+
+        _check_roundtrip(offset)
+        _check_roundtrip(offset2)
+        _check_roundtrip(offset * 2)
+
+    def test_pickle_compat_0_14_1(self, datapath):
+        hdays = [datetime(2013, 1, 1) for ele in range(4)]
+        pth = datapath("tseries", "offsets", "data", "cday-0.14.1.pickle")
+        cday0_14_1 = read_pickle(pth)
+        cday = CDay(holidays=hdays)
+        assert cday == cday0_14_1

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_custom_business_hour.py

@@ -0,0 +1,329 @@
+"""
+Tests for offsets.CustomBusinessHour
+"""
+from __future__ import annotations
+
+from datetime import (
+    datetime,
+    time as dt_time,
+)
+
+import numpy as np
+import pytest
+
+from pandas._libs.tslibs import Timestamp
+from pandas._libs.tslibs.offsets import (
+    BusinessHour,
+    CustomBusinessHour,
+    Nano,
+)
+
+from pandas.tests.tseries.offsets.common import assert_offset_equal
+
+from pandas.tseries.holiday import USFederalHolidayCalendar
+
+holidays = ["2014-06-27", datetime(2014, 6, 30), np.datetime64("2014-07-02")]
+
+
+@pytest.fixture
+def dt():
+    return datetime(2014, 7, 1, 10, 00)
+
+
+@pytest.fixture
+def _offset():
+    return CustomBusinessHour
+
+
+# 2014 Calendar to check custom holidays
+#   Sun Mon Tue Wed Thu Fri Sat
+#  6/22  23  24  25  26  27  28
+#    29  30 7/1   2   3   4   5
+#     6   7   8   9  10  11  12
+@pytest.fixture
+def offset1():
+    return CustomBusinessHour(weekmask="Tue Wed Thu Fri")
+
+
+@pytest.fixture
+def offset2():
+    return CustomBusinessHour(holidays=holidays)
+
+
+class TestCustomBusinessHour:
+    def test_constructor_errors(self):
+        msg = "time data must be specified only with hour and minute"
+        with pytest.raises(ValueError, match=msg):
+            CustomBusinessHour(start=dt_time(11, 0, 5))
+        msg = "time data must match '%H:%M' format"
+        with pytest.raises(ValueError, match=msg):
+            CustomBusinessHour(start="AAA")
+        msg = "time data must match '%H:%M' format"
+        with pytest.raises(ValueError, match=msg):
+            CustomBusinessHour(start="14:00:05")
+
+    def test_different_normalize_equals(self, _offset):
+        # GH#21404 changed __eq__ to return False when `normalize` does not match
+        offset = _offset()
+        offset2 = _offset(normalize=True)
+        assert offset != offset2
+
+    def test_repr(self, offset1, offset2):
+        assert repr(offset1) == "<CustomBusinessHour: cbh=09:00-17:00>"
+        assert repr(offset2) == "<CustomBusinessHour: cbh=09:00-17:00>"
+
+    def test_with_offset(self, dt):
+        expected = Timestamp("2014-07-01 13:00")
+
+        assert dt + CustomBusinessHour() * 3 == expected
+        assert dt + CustomBusinessHour(n=3) == expected
+
+    def test_eq(self, offset1, offset2):
+        for offset in [offset1, offset2]:
+            assert offset == offset
+
+        assert CustomBusinessHour() != CustomBusinessHour(-1)
+        assert CustomBusinessHour(start="09:00") == CustomBusinessHour()
+        assert CustomBusinessHour(start="09:00") != CustomBusinessHour(start="09:01")
+        assert CustomBusinessHour(start="09:00", end="17:00") != CustomBusinessHour(
+            start="17:00", end="09:01"
+        )
+
+        assert CustomBusinessHour(weekmask="Tue Wed Thu Fri") != CustomBusinessHour(
+            weekmask="Mon Tue Wed Thu Fri"
+        )
+        assert CustomBusinessHour(holidays=["2014-06-27"]) != CustomBusinessHour(
+            holidays=["2014-06-28"]
+        )
+
+    def test_hash(self, offset1, offset2):
+        assert hash(offset1) == hash(offset1)
+        assert hash(offset2) == hash(offset2)
+
+    def test_add_dateime(self, dt, offset1, offset2):
+        assert offset1 + dt == datetime(2014, 7, 1, 11)
+        assert offset2 + dt == datetime(2014, 7, 1, 11)
+
+    def testRollback1(self, dt, offset1, offset2):
+        assert offset1.rollback(dt) == dt
+        assert offset2.rollback(dt) == dt
+
+        d = datetime(2014, 7, 1, 0)
+
+        # 2014/07/01 is Tuesday, 06/30 is Monday(holiday)
+        assert offset1.rollback(d) == datetime(2014, 6, 27, 17)
+
+        # 2014/6/30 and 2014/6/27 are holidays
+        assert offset2.rollback(d) == datetime(2014, 6, 26, 17)
+
+    def testRollback2(self, _offset):
+        assert _offset(-3).rollback(datetime(2014, 7, 5, 15, 0)) == datetime(
+            2014, 7, 4, 17, 0
+        )
+
+    def testRollforward1(self, dt, offset1, offset2):
+        assert offset1.rollforward(dt) == dt
+        assert offset2.rollforward(dt) == dt
+
+        d = datetime(2014, 7, 1, 0)
+        assert offset1.rollforward(d) == datetime(2014, 7, 1, 9)
+        assert offset2.rollforward(d) == datetime(2014, 7, 1, 9)
+
+    def testRollforward2(self, _offset):
+        assert _offset(-3).rollforward(datetime(2014, 7, 5, 16, 0)) == datetime(
+            2014, 7, 7, 9
+        )
+
+    def test_roll_date_object(self):
+        offset = BusinessHour()
+
+        dt = datetime(2014, 7, 6, 15, 0)
+
+        result = offset.rollback(dt)
+        assert result == datetime(2014, 7, 4, 17)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2014, 7, 7, 9)
+
+    normalize_cases = [
+        (
+            CustomBusinessHour(normalize=True, holidays=holidays),
+            {
+                datetime(2014, 7, 1, 8): datetime(2014, 7, 1),
+                datetime(2014, 7, 1, 17): datetime(2014, 7, 3),
+                datetime(2014, 7, 1, 16): datetime(2014, 7, 3),
+                datetime(2014, 7, 1, 23): datetime(2014, 7, 3),
+                datetime(2014, 7, 1, 0): datetime(2014, 7, 1),
+                datetime(2014, 7, 4, 15): datetime(2014, 7, 4),
+                datetime(2014, 7, 4, 15, 59): datetime(2014, 7, 4),
+                datetime(2014, 7, 4, 16, 30): datetime(2014, 7, 7),
+                datetime(2014, 7, 5, 23): datetime(2014, 7, 7),
+                datetime(2014, 7, 6, 10): datetime(2014, 7, 7),
+            },
+        ),
+        (
+            CustomBusinessHour(-1, normalize=True, holidays=holidays),
+            {
+                datetime(2014, 7, 1, 8): datetime(2014, 6, 26),
+                datetime(2014, 7, 1, 17): datetime(2014, 7, 1),
+                datetime(2014, 7, 1, 16): datetime(2014, 7, 1),
+                datetime(2014, 7, 1, 10): datetime(2014, 6, 26),
+                datetime(2014, 7, 1, 0): datetime(2014, 6, 26),
+                datetime(2014, 7, 7, 10): datetime(2014, 7, 4),
+                datetime(2014, 7, 7, 10, 1): datetime(2014, 7, 7),
+                datetime(2014, 7, 5, 23): datetime(2014, 7, 4),
+                datetime(2014, 7, 6, 10): datetime(2014, 7, 4),
+            },
+        ),
+        (
+            CustomBusinessHour(
+                1, normalize=True, start="17:00", end="04:00", holidays=holidays
+            ),
+            {
+                datetime(2014, 7, 1, 8): datetime(2014, 7, 1),
+                datetime(2014, 7, 1, 17): datetime(2014, 7, 1),
+                datetime(2014, 7, 1, 23): datetime(2014, 7, 2),
+                datetime(2014, 7, 2, 2): datetime(2014, 7, 2),
+                datetime(2014, 7, 2, 3): datetime(2014, 7, 3),
+                datetime(2014, 7, 4, 23): datetime(2014, 7, 5),
+                datetime(2014, 7, 5, 2): datetime(2014, 7, 5),
+                datetime(2014, 7, 7, 2): datetime(2014, 7, 7),
+                datetime(2014, 7, 7, 17): datetime(2014, 7, 7),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("norm_cases", normalize_cases)
+    def test_normalize(self, norm_cases):
+        offset, cases = norm_cases
+        for dt, expected in cases.items():
+            assert offset._apply(dt) == expected
+
+    @pytest.mark.parametrize(
+        "dt, expected",
+        [
+            [datetime(2014, 7, 1, 9), False],
+            [datetime(2014, 7, 1, 10), True],
+            [datetime(2014, 7, 1, 15), True],
+            [datetime(2014, 7, 1, 15, 1), False],
+            [datetime(2014, 7, 5, 12), False],
+            [datetime(2014, 7, 6, 12), False],
+        ],
+    )
+    def test_is_on_offset(self, dt, expected):
+        offset = CustomBusinessHour(start="10:00", end="15:00", holidays=holidays)
+        assert offset.is_on_offset(dt) == expected
+
+    apply_cases = [
+        (
+            CustomBusinessHour(holidays=holidays),
+            {
+                datetime(2014, 7, 1, 11): datetime(2014, 7, 1, 12),
+                datetime(2014, 7, 1, 13): datetime(2014, 7, 1, 14),
+                datetime(2014, 7, 1, 15): datetime(2014, 7, 1, 16),
+                datetime(2014, 7, 1, 19): datetime(2014, 7, 3, 10),
+                datetime(2014, 7, 1, 16): datetime(2014, 7, 3, 9),
+                datetime(2014, 7, 1, 16, 30, 15): datetime(2014, 7, 3, 9, 30, 15),
+                datetime(2014, 7, 1, 17): datetime(2014, 7, 3, 10),
+                datetime(2014, 7, 2, 11): datetime(2014, 7, 3, 10),
+                # out of business hours
+                datetime(2014, 7, 2, 8): datetime(2014, 7, 3, 10),
+                datetime(2014, 7, 2, 19): datetime(2014, 7, 3, 10),
+                datetime(2014, 7, 2, 23): datetime(2014, 7, 3, 10),
+                datetime(2014, 7, 3, 0): datetime(2014, 7, 3, 10),
+                # saturday
+                datetime(2014, 7, 5, 15): datetime(2014, 7, 7, 10),
+                datetime(2014, 7, 4, 17): datetime(2014, 7, 7, 10),
+                datetime(2014, 7, 4, 16, 30): datetime(2014, 7, 7, 9, 30),
+                datetime(2014, 7, 4, 16, 30, 30): datetime(2014, 7, 7, 9, 30, 30),
+            },
+        ),
+        (
+            CustomBusinessHour(4, holidays=holidays),
+            {
+                datetime(2014, 7, 1, 11): datetime(2014, 7, 1, 15),
+                datetime(2014, 7, 1, 13): datetime(2014, 7, 3, 9),
+                datetime(2014, 7, 1, 15): datetime(2014, 7, 3, 11),
+                datetime(2014, 7, 1, 16): datetime(2014, 7, 3, 12),
+                datetime(2014, 7, 1, 17): datetime(2014, 7, 3, 13),
+                datetime(2014, 7, 2, 11): datetime(2014, 7, 3, 13),
+                datetime(2014, 7, 2, 8): datetime(2014, 7, 3, 13),
+                datetime(2014, 7, 2, 19): datetime(2014, 7, 3, 13),
+                datetime(2014, 7, 2, 23): datetime(2014, 7, 3, 13),
+                datetime(2014, 7, 3, 0): datetime(2014, 7, 3, 13),
+                datetime(2014, 7, 5, 15): datetime(2014, 7, 7, 13),
+                datetime(2014, 7, 4, 17): datetime(2014, 7, 7, 13),
+                datetime(2014, 7, 4, 16, 30): datetime(2014, 7, 7, 12, 30),
+                datetime(2014, 7, 4, 16, 30, 30): datetime(2014, 7, 7, 12, 30, 30),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("apply_case", apply_cases)
+    def test_apply(self, apply_case):
+        offset, cases = apply_case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    nano_cases = [
+        (
+            CustomBusinessHour(holidays=holidays),
+            {
+                Timestamp("2014-07-01 15:00")
+                + Nano(5): Timestamp("2014-07-01 16:00")
+                + Nano(5),
+                Timestamp("2014-07-01 16:00")
+                + Nano(5): Timestamp("2014-07-03 09:00")
+                + Nano(5),
+                Timestamp("2014-07-01 16:00")
+                - Nano(5): Timestamp("2014-07-01 17:00")
+                - Nano(5),
+            },
+        ),
+        (
+            CustomBusinessHour(-1, holidays=holidays),
+            {
+                Timestamp("2014-07-01 15:00")
+                + Nano(5): Timestamp("2014-07-01 14:00")
+                + Nano(5),
+                Timestamp("2014-07-01 10:00")
+                + Nano(5): Timestamp("2014-07-01 09:00")
+                + Nano(5),
+                Timestamp("2014-07-01 10:00")
+                - Nano(5): Timestamp("2014-06-26 17:00")
+                - Nano(5),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("nano_case", nano_cases)
+    def test_apply_nanoseconds(self, nano_case):
+        offset, cases = nano_case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    def test_us_federal_holiday_with_datetime(self):
+        # GH 16867
+        bhour_us = CustomBusinessHour(calendar=USFederalHolidayCalendar())
+        t0 = datetime(2014, 1, 17, 15)
+        result = t0 + bhour_us * 8
+        expected = Timestamp("2014-01-21 15:00:00")
+        assert result == expected
+
+
+@pytest.mark.parametrize(
+    "weekmask, expected_time, mult",
+    [
+        ["Mon Tue Wed Thu Fri Sat", "2018-11-10 09:00:00", 10],
+        ["Tue Wed Thu Fri Sat", "2018-11-13 08:00:00", 18],
+    ],
+)
+def test_custom_businesshour_weekmask_and_holidays(weekmask, expected_time, mult):
+    # GH 23542
+    holidays = ["2018-11-09"]
+    bh = CustomBusinessHour(
+        start="08:00", end="17:00", weekmask=weekmask, holidays=holidays
+    )
+    result = Timestamp("2018-11-08 08:00") + mult * bh
+    expected = Timestamp(expected_time)
+    assert result == expected

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_custom_business_month.py

@@ -0,0 +1,437 @@
+"""
+Tests for the following offsets:
+- CustomBusinessMonthBase
+- CustomBusinessMonthBegin
+- CustomBusinessMonthEnd
+"""
+from __future__ import annotations
+
+from datetime import (
+    date,
+    datetime,
+    timedelta,
+)
+
+import numpy as np
+import pytest
+
+from pandas._libs.tslibs.offsets import (
+    CBMonthBegin,
+    CBMonthEnd,
+    CDay,
+)
+
+import pandas._testing as tm
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries import offsets
+
+
+@pytest.fixture
+def dt():
+    return datetime(2008, 1, 1)
+
+
+class TestCommonCBM:
+    @pytest.mark.parametrize("offset2", [CBMonthBegin(2), CBMonthEnd(2)])
+    def test_eq(self, offset2):
+        assert offset2 == offset2
+
+    @pytest.mark.parametrize("offset2", [CBMonthBegin(2), CBMonthEnd(2)])
+    def test_hash(self, offset2):
+        assert hash(offset2) == hash(offset2)
+
+    @pytest.mark.parametrize("_offset", [CBMonthBegin, CBMonthEnd])
+    def test_roundtrip_pickle(self, _offset):
+        def _check_roundtrip(obj):
+            unpickled = tm.round_trip_pickle(obj)
+            assert unpickled == obj
+
+        _check_roundtrip(_offset())
+        _check_roundtrip(_offset(2))
+        _check_roundtrip(_offset() * 2)
+
+    @pytest.mark.parametrize("_offset", [CBMonthBegin, CBMonthEnd])
+    def test_copy(self, _offset):
+        # GH 17452
+        off = _offset(weekmask="Mon Wed Fri")
+        assert off == off.copy()
+
+
+class TestCustomBusinessMonthBegin:
+    @pytest.fixture
+    def _offset(self):
+        return CBMonthBegin
+
+    @pytest.fixture
+    def offset(self):
+        return CBMonthBegin()
+
+    @pytest.fixture
+    def offset2(self):
+        return CBMonthBegin(2)
+
+    def test_different_normalize_equals(self, _offset):
+        # GH#21404 changed __eq__ to return False when `normalize` does not match
+        offset = _offset()
+        offset2 = _offset(normalize=True)
+        assert offset != offset2
+
+    def test_repr(self, offset, offset2):
+        assert repr(offset) == "<CustomBusinessMonthBegin>"
+        assert repr(offset2) == "<2 * CustomBusinessMonthBegins>"
+
+    def test_add_datetime(self, dt, offset2):
+        assert offset2 + dt == datetime(2008, 3, 3)
+
+    def testRollback1(self):
+        assert CDay(10).rollback(datetime(2007, 12, 31)) == datetime(2007, 12, 31)
+
+    def testRollback2(self, dt):
+        assert CBMonthBegin(10).rollback(dt) == datetime(2008, 1, 1)
+
+    def testRollforward1(self, dt):
+        assert CBMonthBegin(10).rollforward(dt) == datetime(2008, 1, 1)
+
+    def test_roll_date_object(self):
+        offset = CBMonthBegin()
+
+        dt = date(2012, 9, 15)
+
+        result = offset.rollback(dt)
+        assert result == datetime(2012, 9, 3)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2012, 10, 1)
+
+        offset = offsets.Day()
+        result = offset.rollback(dt)
+        assert result == datetime(2012, 9, 15)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2012, 9, 15)
+
+    on_offset_cases = [
+        (CBMonthBegin(), datetime(2008, 1, 1), True),
+        (CBMonthBegin(), datetime(2008, 1, 31), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+    apply_cases = [
+        (
+            CBMonthBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 1),
+                datetime(2008, 2, 7): datetime(2008, 3, 3),
+            },
+        ),
+        (
+            2 * CBMonthBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 3, 3),
+                datetime(2008, 2, 7): datetime(2008, 4, 1),
+            },
+        ),
+        (
+            -CBMonthBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2007, 12, 3),
+                datetime(2008, 2, 8): datetime(2008, 2, 1),
+            },
+        ),
+        (
+            -2 * CBMonthBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2007, 11, 1),
+                datetime(2008, 2, 9): datetime(2008, 1, 1),
+            },
+        ),
+        (
+            CBMonthBegin(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 1, 7): datetime(2008, 2, 1),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("case", apply_cases)
+    def test_apply(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    def test_apply_large_n(self):
+        dt = datetime(2012, 10, 23)
+
+        result = dt + CBMonthBegin(10)
+        assert result == datetime(2013, 8, 1)
+
+        result = dt + CDay(100) - CDay(100)
+        assert result == dt
+
+        off = CBMonthBegin() * 6
+        rs = datetime(2012, 1, 1) - off
+        xp = datetime(2011, 7, 1)
+        assert rs == xp
+
+        st = datetime(2011, 12, 18)
+        rs = st + off
+
+        xp = datetime(2012, 6, 1)
+        assert rs == xp
+
+    def test_holidays(self):
+        # Define a TradingDay offset
+        holidays = ["2012-02-01", datetime(2012, 2, 2), np.datetime64("2012-03-01")]
+        bm_offset = CBMonthBegin(holidays=holidays)
+        dt = datetime(2012, 1, 1)
+
+        assert dt + bm_offset == datetime(2012, 1, 2)
+        assert dt + 2 * bm_offset == datetime(2012, 2, 3)
+
+    @pytest.mark.parametrize(
+        "case",
+        [
+            (
+                CBMonthBegin(n=1, offset=timedelta(days=5)),
+                {
+                    datetime(2021, 3, 1): datetime(2021, 4, 1) + timedelta(days=5),
+                    datetime(2021, 4, 17): datetime(2021, 5, 3) + timedelta(days=5),
+                },
+            ),
+            (
+                CBMonthBegin(n=2, offset=timedelta(days=40)),
+                {
+                    datetime(2021, 3, 10): datetime(2021, 5, 3) + timedelta(days=40),
+                    datetime(2021, 4, 30): datetime(2021, 6, 1) + timedelta(days=40),
+                },
+            ),
+            (
+                CBMonthBegin(n=1, offset=timedelta(days=-5)),
+                {
+                    datetime(2021, 3, 1): datetime(2021, 4, 1) - timedelta(days=5),
+                    datetime(2021, 4, 11): datetime(2021, 5, 3) - timedelta(days=5),
+                },
+            ),
+            (
+                -2 * CBMonthBegin(n=1, offset=timedelta(days=10)),
+                {
+                    datetime(2021, 3, 1): datetime(2021, 1, 1) + timedelta(days=10),
+                    datetime(2021, 4, 3): datetime(2021, 3, 1) + timedelta(days=10),
+                },
+            ),
+            (
+                CBMonthBegin(n=0, offset=timedelta(days=1)),
+                {
+                    datetime(2021, 3, 2): datetime(2021, 4, 1) + timedelta(days=1),
+                    datetime(2021, 4, 1): datetime(2021, 4, 1) + timedelta(days=1),
+                },
+            ),
+            (
+                CBMonthBegin(
+                    n=1, holidays=["2021-04-01", "2021-04-02"], offset=timedelta(days=1)
+                ),
+                {
+                    datetime(2021, 3, 2): datetime(2021, 4, 5) + timedelta(days=1),
+                },
+            ),
+        ],
+    )
+    def test_apply_with_extra_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+
+class TestCustomBusinessMonthEnd:
+    @pytest.fixture
+    def _offset(self):
+        return CBMonthEnd
+
+    @pytest.fixture
+    def offset(self):
+        return CBMonthEnd()
+
+    @pytest.fixture
+    def offset2(self):
+        return CBMonthEnd(2)
+
+    def test_different_normalize_equals(self, _offset):
+        # GH#21404 changed __eq__ to return False when `normalize` does not match
+        offset = _offset()
+        offset2 = _offset(normalize=True)
+        assert offset != offset2
+
+    def test_repr(self, offset, offset2):
+        assert repr(offset) == "<CustomBusinessMonthEnd>"
+        assert repr(offset2) == "<2 * CustomBusinessMonthEnds>"
+
+    def test_add_datetime(self, dt, offset2):
+        assert offset2 + dt == datetime(2008, 2, 29)
+
+    def testRollback1(self):
+        assert CDay(10).rollback(datetime(2007, 12, 31)) == datetime(2007, 12, 31)
+
+    def testRollback2(self, dt):
+        assert CBMonthEnd(10).rollback(dt) == datetime(2007, 12, 31)
+
+    def testRollforward1(self, dt):
+        assert CBMonthEnd(10).rollforward(dt) == datetime(2008, 1, 31)
+
+    def test_roll_date_object(self):
+        offset = CBMonthEnd()
+
+        dt = date(2012, 9, 15)
+
+        result = offset.rollback(dt)
+        assert result == datetime(2012, 8, 31)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2012, 9, 28)
+
+        offset = offsets.Day()
+        result = offset.rollback(dt)
+        assert result == datetime(2012, 9, 15)
+
+        result = offset.rollforward(dt)
+        assert result == datetime(2012, 9, 15)
+
+    on_offset_cases = [
+        (CBMonthEnd(), datetime(2008, 1, 31), True),
+        (CBMonthEnd(), datetime(2008, 1, 1), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+    apply_cases = [
+        (
+            CBMonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 2, 7): datetime(2008, 2, 29),
+            },
+        ),
+        (
+            2 * CBMonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 29),
+                datetime(2008, 2, 7): datetime(2008, 3, 31),
+            },
+        ),
+        (
+            -CBMonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2007, 12, 31),
+                datetime(2008, 2, 8): datetime(2008, 1, 31),
+            },
+        ),
+        (
+            -2 * CBMonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2007, 11, 30),
+                datetime(2008, 2, 9): datetime(2007, 12, 31),
+            },
+        ),
+        (
+            CBMonthEnd(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 2, 7): datetime(2008, 2, 29),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("case", apply_cases)
+    def test_apply(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    def test_apply_large_n(self):
+        dt = datetime(2012, 10, 23)
+
+        result = dt + CBMonthEnd(10)
+        assert result == datetime(2013, 7, 31)
+
+        result = dt + CDay(100) - CDay(100)
+        assert result == dt
+
+        off = CBMonthEnd() * 6
+        rs = datetime(2012, 1, 1) - off
+        xp = datetime(2011, 7, 29)
+        assert rs == xp
+
+        st = datetime(2011, 12, 18)
+        rs = st + off
+        xp = datetime(2012, 5, 31)
+        assert rs == xp
+
+    def test_holidays(self):
+        # Define a TradingDay offset
+        holidays = ["2012-01-31", datetime(2012, 2, 28), np.datetime64("2012-02-29")]
+        bm_offset = CBMonthEnd(holidays=holidays)
+        dt = datetime(2012, 1, 1)
+        assert dt + bm_offset == datetime(2012, 1, 30)
+        assert dt + 2 * bm_offset == datetime(2012, 2, 27)
+
+    @pytest.mark.parametrize(
+        "case",
+        [
+            (
+                CBMonthEnd(n=1, offset=timedelta(days=5)),
+                {
+                    datetime(2021, 3, 1): datetime(2021, 3, 31) + timedelta(days=5),
+                    datetime(2021, 4, 17): datetime(2021, 4, 30) + timedelta(days=5),
+                },
+            ),
+            (
+                CBMonthEnd(n=2, offset=timedelta(days=40)),
+                {
+                    datetime(2021, 3, 10): datetime(2021, 4, 30) + timedelta(days=40),
+                    datetime(2021, 4, 30): datetime(2021, 6, 30) + timedelta(days=40),
+                },
+            ),
+            (
+                CBMonthEnd(n=1, offset=timedelta(days=-5)),
+                {
+                    datetime(2021, 3, 1): datetime(2021, 3, 31) - timedelta(days=5),
+                    datetime(2021, 4, 11): datetime(2021, 4, 30) - timedelta(days=5),
+                },
+            ),
+            (
+                -2 * CBMonthEnd(n=1, offset=timedelta(days=10)),
+                {
+                    datetime(2021, 3, 1): datetime(2021, 1, 29) + timedelta(days=10),
+                    datetime(2021, 4, 3): datetime(2021, 2, 26) + timedelta(days=10),
+                },
+            ),
+            (
+                CBMonthEnd(n=0, offset=timedelta(days=1)),
+                {
+                    datetime(2021, 3, 2): datetime(2021, 3, 31) + timedelta(days=1),
+                    datetime(2021, 4, 1): datetime(2021, 4, 30) + timedelta(days=1),
+                },
+            ),
+            (
+                CBMonthEnd(n=1, holidays=["2021-03-31"], offset=timedelta(days=1)),
+                {
+                    datetime(2021, 3, 2): datetime(2021, 3, 30) + timedelta(days=1),
+                },
+            ),
+        ],
+    )
+    def test_apply_with_extra_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_dst.py

@@ -0,0 +1,260 @@
+"""
+Tests for DateOffset additions over Daylight Savings Time
+"""
+from datetime import timedelta
+
+import pytest
+import pytz
+
+from pandas._libs.tslibs import Timestamp
+from pandas._libs.tslibs.offsets import (
+    BMonthBegin,
+    BMonthEnd,
+    BQuarterBegin,
+    BQuarterEnd,
+    BYearBegin,
+    BYearEnd,
+    CBMonthBegin,
+    CBMonthEnd,
+    CustomBusinessDay,
+    DateOffset,
+    Day,
+    MonthBegin,
+    MonthEnd,
+    QuarterBegin,
+    QuarterEnd,
+    SemiMonthBegin,
+    SemiMonthEnd,
+    Week,
+    YearBegin,
+    YearEnd,
+)
+from pandas.errors import PerformanceWarning
+
+from pandas import DatetimeIndex
+import pandas._testing as tm
+from pandas.util.version import Version
+
+# error: Module has no attribute "__version__"
+pytz_version = Version(pytz.__version__)  # type: ignore[attr-defined]
+
+
+def get_utc_offset_hours(ts):
+    # take a Timestamp and compute total hours of utc offset
+    o = ts.utcoffset()
+    return (o.days * 24 * 3600 + o.seconds) / 3600.0
+
+
+class TestDST:
+    # one microsecond before the DST transition
+    ts_pre_fallback = "2013-11-03 01:59:59.999999"
+    ts_pre_springfwd = "2013-03-10 01:59:59.999999"
+
+    # test both basic names and dateutil timezones
+    timezone_utc_offsets = {
+        "US/Eastern": {"utc_offset_daylight": -4, "utc_offset_standard": -5},
+        "dateutil/US/Pacific": {"utc_offset_daylight": -7, "utc_offset_standard": -8},
+    }
+    valid_date_offsets_singular = [
+        "weekday",
+        "day",
+        "hour",
+        "minute",
+        "second",
+        "microsecond",
+    ]
+    valid_date_offsets_plural = [
+        "weeks",
+        "days",
+        "hours",
+        "minutes",
+        "seconds",
+        "milliseconds",
+        "microseconds",
+    ]
+
+    def _test_all_offsets(self, n, **kwds):
+        valid_offsets = (
+            self.valid_date_offsets_plural
+            if n > 1
+            else self.valid_date_offsets_singular
+        )
+
+        for name in valid_offsets:
+            self._test_offset(offset_name=name, offset_n=n, **kwds)
+
+    def _test_offset(self, offset_name, offset_n, tstart, expected_utc_offset):
+        offset = DateOffset(**{offset_name: offset_n})
+
+        if (
+            offset_name in ["hour", "minute", "second", "microsecond"]
+            and offset_n == 1
+            and tstart == Timestamp("2013-11-03 01:59:59.999999-0500", tz="US/Eastern")
+        ):
+            # This addition results in an ambiguous wall time
+            err_msg = {
+                "hour": "2013-11-03 01:59:59.999999",
+                "minute": "2013-11-03 01:01:59.999999",
+                "second": "2013-11-03 01:59:01.999999",
+                "microsecond": "2013-11-03 01:59:59.000001",
+            }[offset_name]
+            with pytest.raises(pytz.AmbiguousTimeError, match=err_msg):
+                tstart + offset
+            # While we're here, let's check that we get the same behavior in a
+            #  vectorized path
+            dti = DatetimeIndex([tstart])
+            warn_msg = "Non-vectorized DateOffset"
+            with pytest.raises(pytz.AmbiguousTimeError, match=err_msg):
+                with tm.assert_produces_warning(PerformanceWarning, match=warn_msg):
+                    dti + offset
+            return
+
+        t = tstart + offset
+        if expected_utc_offset is not None:
+            assert get_utc_offset_hours(t) == expected_utc_offset
+
+        if offset_name == "weeks":
+            # dates should match
+            assert t.date() == timedelta(days=7 * offset.kwds["weeks"]) + tstart.date()
+            # expect the same day of week, hour of day, minute, second, ...
+            assert (
+                t.dayofweek == tstart.dayofweek
+                and t.hour == tstart.hour
+                and t.minute == tstart.minute
+                and t.second == tstart.second
+            )
+        elif offset_name == "days":
+            # dates should match
+            assert timedelta(offset.kwds["days"]) + tstart.date() == t.date()
+            # expect the same hour of day, minute, second, ...
+            assert (
+                t.hour == tstart.hour
+                and t.minute == tstart.minute
+                and t.second == tstart.second
+            )
+        elif offset_name in self.valid_date_offsets_singular:
+            # expect the singular offset value to match between tstart and t
+            datepart_offset = getattr(
+                t, offset_name if offset_name != "weekday" else "dayofweek"
+            )
+            assert datepart_offset == offset.kwds[offset_name]
+        else:
+            # the offset should be the same as if it was done in UTC
+            assert t == (tstart.tz_convert("UTC") + offset).tz_convert("US/Pacific")
+
+    def _make_timestamp(self, string, hrs_offset, tz):
+        if hrs_offset >= 0:
+            offset_string = f"{hrs_offset:02d}00"
+        else:
+            offset_string = f"-{(hrs_offset * -1):02}00"
+        return Timestamp(string + offset_string).tz_convert(tz)
+
+    def test_springforward_plural(self):
+        # test moving from standard to daylight savings
+        for tz, utc_offsets in self.timezone_utc_offsets.items():
+            hrs_pre = utc_offsets["utc_offset_standard"]
+            hrs_post = utc_offsets["utc_offset_daylight"]
+            self._test_all_offsets(
+                n=3,
+                tstart=self._make_timestamp(self.ts_pre_springfwd, hrs_pre, tz),
+                expected_utc_offset=hrs_post,
+            )
+
+    def test_fallback_singular(self):
+        # in the case of singular offsets, we don't necessarily know which utc
+        # offset the new Timestamp will wind up in (the tz for 1 month may be
+        # different from 1 second) so we don't specify an expected_utc_offset
+        for tz, utc_offsets in self.timezone_utc_offsets.items():
+            hrs_pre = utc_offsets["utc_offset_standard"]
+            self._test_all_offsets(
+                n=1,
+                tstart=self._make_timestamp(self.ts_pre_fallback, hrs_pre, tz),
+                expected_utc_offset=None,
+            )
+
+    def test_springforward_singular(self):
+        for tz, utc_offsets in self.timezone_utc_offsets.items():
+            hrs_pre = utc_offsets["utc_offset_standard"]
+            self._test_all_offsets(
+                n=1,
+                tstart=self._make_timestamp(self.ts_pre_springfwd, hrs_pre, tz),
+                expected_utc_offset=None,
+            )
+
+    offset_classes = {
+        MonthBegin: ["11/2/2012", "12/1/2012"],
+        MonthEnd: ["11/2/2012", "11/30/2012"],
+        BMonthBegin: ["11/2/2012", "12/3/2012"],
+        BMonthEnd: ["11/2/2012", "11/30/2012"],
+        CBMonthBegin: ["11/2/2012", "12/3/2012"],
+        CBMonthEnd: ["11/2/2012", "11/30/2012"],
+        SemiMonthBegin: ["11/2/2012", "11/15/2012"],
+        SemiMonthEnd: ["11/2/2012", "11/15/2012"],
+        Week: ["11/2/2012", "11/9/2012"],
+        YearBegin: ["11/2/2012", "1/1/2013"],
+        YearEnd: ["11/2/2012", "12/31/2012"],
+        BYearBegin: ["11/2/2012", "1/1/2013"],
+        BYearEnd: ["11/2/2012", "12/31/2012"],
+        QuarterBegin: ["11/2/2012", "12/1/2012"],
+        QuarterEnd: ["11/2/2012", "12/31/2012"],
+        BQuarterBegin: ["11/2/2012", "12/3/2012"],
+        BQuarterEnd: ["11/2/2012", "12/31/2012"],
+        Day: ["11/4/2012", "11/4/2012 23:00"],
+    }.items()
+
+    @pytest.mark.parametrize("tup", offset_classes)
+    def test_all_offset_classes(self, tup):
+        offset, test_values = tup
+
+        first = Timestamp(test_values[0], tz="US/Eastern") + offset()
+        second = Timestamp(test_values[1], tz="US/Eastern")
+        assert first == second
+
+
+@pytest.mark.parametrize(
+    "original_dt, target_dt, offset, tz",
+    [
+        pytest.param(
+            Timestamp("1900-01-01"),
+            Timestamp("1905-07-01"),
+            MonthBegin(66),
+            "Africa/Lagos",
+            marks=pytest.mark.xfail(
+                pytz_version < Version("2020.5") or pytz_version == Version("2022.2"),
+                reason="GH#41906: pytz utc transition dates changed",
+            ),
+        ),
+        (
+            Timestamp("2021-10-01 01:15"),
+            Timestamp("2021-10-31 01:15"),
+            MonthEnd(1),
+            "Europe/London",
+        ),
+        (
+            Timestamp("2010-12-05 02:59"),
+            Timestamp("2010-10-31 02:59"),
+            SemiMonthEnd(-3),
+            "Europe/Paris",
+        ),
+        (
+            Timestamp("2021-10-31 01:20"),
+            Timestamp("2021-11-07 01:20"),
+            CustomBusinessDay(2, weekmask="Sun Mon"),
+            "US/Eastern",
+        ),
+        (
+            Timestamp("2020-04-03 01:30"),
+            Timestamp("2020-11-01 01:30"),
+            YearBegin(1, month=11),
+            "America/Chicago",
+        ),
+    ],
+)
+def test_nontick_offset_with_ambiguous_time_error(original_dt, target_dt, offset, tz):
+    # .apply for non-Tick offsets throws AmbiguousTimeError when the target dt
+    # is dst-ambiguous
+    localized_dt = original_dt.tz_localize(tz)
+
+    msg = f"Cannot infer dst time from {target_dt}, try using the 'ambiguous' argument"
+    with pytest.raises(pytz.AmbiguousTimeError, match=msg):
+        localized_dt + offset

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_easter.py

@@ -0,0 +1,33 @@
+"""
+Tests for the following offsets:
+- Easter
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+
+from pandas.tests.tseries.offsets.common import assert_offset_equal
+
+from pandas.tseries.offsets import Easter
+
+
+class TestEaster:
+    @pytest.mark.parametrize(
+        "offset,date,expected",
+        [
+            (Easter(), datetime(2010, 1, 1), datetime(2010, 4, 4)),
+            (Easter(), datetime(2010, 4, 5), datetime(2011, 4, 24)),
+            (Easter(2), datetime(2010, 1, 1), datetime(2011, 4, 24)),
+            (Easter(), datetime(2010, 4, 4), datetime(2011, 4, 24)),
+            (Easter(2), datetime(2010, 4, 4), datetime(2012, 4, 8)),
+            (-Easter(), datetime(2011, 1, 1), datetime(2010, 4, 4)),
+            (-Easter(), datetime(2010, 4, 5), datetime(2010, 4, 4)),
+            (-Easter(2), datetime(2011, 1, 1), datetime(2009, 4, 12)),
+            (-Easter(), datetime(2010, 4, 4), datetime(2009, 4, 12)),
+            (-Easter(2), datetime(2010, 4, 4), datetime(2008, 3, 23)),
+        ],
+    )
+    def test_offset(self, offset, date, expected):
+        assert_offset_equal(offset, date, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_fiscal.py

@@ -0,0 +1,656 @@
+"""
+Tests for Fiscal Year and Fiscal Quarter offset classes
+"""
+from datetime import datetime
+
+from dateutil.relativedelta import relativedelta
+import pytest
+
+from pandas import Timestamp
+import pandas._testing as tm
+from pandas.tests.tseries.offsets.common import (
+    WeekDay,
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries.offsets import (
+    FY5253,
+    FY5253Quarter,
+)
+
+
+def makeFY5253LastOfMonthQuarter(*args, **kwds):
+    return FY5253Quarter(*args, variation="last", **kwds)
+
+
+def makeFY5253NearestEndMonthQuarter(*args, **kwds):
+    return FY5253Quarter(*args, variation="nearest", **kwds)
+
+
+def makeFY5253NearestEndMonth(*args, **kwds):
+    return FY5253(*args, variation="nearest", **kwds)
+
+
+def makeFY5253LastOfMonth(*args, **kwds):
+    return FY5253(*args, variation="last", **kwds)
+
+
+def test_get_offset_name():
+    assert (
+        makeFY5253LastOfMonthQuarter(
+            weekday=1, startingMonth=3, qtr_with_extra_week=4
+        ).freqstr
+        == "REQ-L-MAR-TUE-4"
+    )
+    assert (
+        makeFY5253NearestEndMonthQuarter(
+            weekday=1, startingMonth=3, qtr_with_extra_week=3
+        ).freqstr
+        == "REQ-N-MAR-TUE-3"
+    )
+
+
+class TestFY5253LastOfMonth:
+    offset_lom_sat_aug = makeFY5253LastOfMonth(1, startingMonth=8, weekday=WeekDay.SAT)
+    offset_lom_sat_sep = makeFY5253LastOfMonth(1, startingMonth=9, weekday=WeekDay.SAT)
+
+    on_offset_cases = [
+        # From Wikipedia (see:
+        # https://en.wikipedia.org/wiki/4%E2%80%934%E2%80%935_calendar#Last_Saturday_of_the_month_at_fiscal_year_end)
+        (offset_lom_sat_aug, datetime(2006, 8, 26), True),
+        (offset_lom_sat_aug, datetime(2007, 8, 25), True),
+        (offset_lom_sat_aug, datetime(2008, 8, 30), True),
+        (offset_lom_sat_aug, datetime(2009, 8, 29), True),
+        (offset_lom_sat_aug, datetime(2010, 8, 28), True),
+        (offset_lom_sat_aug, datetime(2011, 8, 27), True),
+        (offset_lom_sat_aug, datetime(2012, 8, 25), True),
+        (offset_lom_sat_aug, datetime(2013, 8, 31), True),
+        (offset_lom_sat_aug, datetime(2014, 8, 30), True),
+        (offset_lom_sat_aug, datetime(2015, 8, 29), True),
+        (offset_lom_sat_aug, datetime(2016, 8, 27), True),
+        (offset_lom_sat_aug, datetime(2017, 8, 26), True),
+        (offset_lom_sat_aug, datetime(2018, 8, 25), True),
+        (offset_lom_sat_aug, datetime(2019, 8, 31), True),
+        (offset_lom_sat_aug, datetime(2006, 8, 27), False),
+        (offset_lom_sat_aug, datetime(2007, 8, 28), False),
+        (offset_lom_sat_aug, datetime(2008, 8, 31), False),
+        (offset_lom_sat_aug, datetime(2009, 8, 30), False),
+        (offset_lom_sat_aug, datetime(2010, 8, 29), False),
+        (offset_lom_sat_aug, datetime(2011, 8, 28), False),
+        (offset_lom_sat_aug, datetime(2006, 8, 25), False),
+        (offset_lom_sat_aug, datetime(2007, 8, 24), False),
+        (offset_lom_sat_aug, datetime(2008, 8, 29), False),
+        (offset_lom_sat_aug, datetime(2009, 8, 28), False),
+        (offset_lom_sat_aug, datetime(2010, 8, 27), False),
+        (offset_lom_sat_aug, datetime(2011, 8, 26), False),
+        (offset_lom_sat_aug, datetime(2019, 8, 30), False),
+        # From GMCR (see for example:
+        # http://yahoo.brand.edgar-online.com/Default.aspx?
+        # companyid=3184&formtypeID=7)
+        (offset_lom_sat_sep, datetime(2010, 9, 25), True),
+        (offset_lom_sat_sep, datetime(2011, 9, 24), True),
+        (offset_lom_sat_sep, datetime(2012, 9, 29), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+    def test_apply(self):
+        offset_lom_aug_sat = makeFY5253LastOfMonth(startingMonth=8, weekday=WeekDay.SAT)
+        offset_lom_aug_sat_1 = makeFY5253LastOfMonth(
+            n=1, startingMonth=8, weekday=WeekDay.SAT
+        )
+
+        date_seq_lom_aug_sat = [
+            datetime(2006, 8, 26),
+            datetime(2007, 8, 25),
+            datetime(2008, 8, 30),
+            datetime(2009, 8, 29),
+            datetime(2010, 8, 28),
+            datetime(2011, 8, 27),
+            datetime(2012, 8, 25),
+            datetime(2013, 8, 31),
+            datetime(2014, 8, 30),
+            datetime(2015, 8, 29),
+            datetime(2016, 8, 27),
+        ]
+
+        tests = [
+            (offset_lom_aug_sat, date_seq_lom_aug_sat),
+            (offset_lom_aug_sat_1, date_seq_lom_aug_sat),
+            (offset_lom_aug_sat, [datetime(2006, 8, 25)] + date_seq_lom_aug_sat),
+            (offset_lom_aug_sat_1, [datetime(2006, 8, 27)] + date_seq_lom_aug_sat[1:]),
+            (
+                makeFY5253LastOfMonth(n=-1, startingMonth=8, weekday=WeekDay.SAT),
+                list(reversed(date_seq_lom_aug_sat)),
+            ),
+        ]
+        for test in tests:
+            offset, data = test
+            current = data[0]
+            for datum in data[1:]:
+                current = current + offset
+                assert current == datum
+
+
+class TestFY5253NearestEndMonth:
+    def test_get_year_end(self):
+        assert makeFY5253NearestEndMonth(
+            startingMonth=8, weekday=WeekDay.SAT
+        ).get_year_end(datetime(2013, 1, 1)) == datetime(2013, 8, 31)
+        assert makeFY5253NearestEndMonth(
+            startingMonth=8, weekday=WeekDay.SUN
+        ).get_year_end(datetime(2013, 1, 1)) == datetime(2013, 9, 1)
+        assert makeFY5253NearestEndMonth(
+            startingMonth=8, weekday=WeekDay.FRI
+        ).get_year_end(datetime(2013, 1, 1)) == datetime(2013, 8, 30)
+
+        offset_n = FY5253(weekday=WeekDay.TUE, startingMonth=12, variation="nearest")
+        assert offset_n.get_year_end(datetime(2012, 1, 1)) == datetime(2013, 1, 1)
+        assert offset_n.get_year_end(datetime(2012, 1, 10)) == datetime(2013, 1, 1)
+
+        assert offset_n.get_year_end(datetime(2013, 1, 1)) == datetime(2013, 12, 31)
+        assert offset_n.get_year_end(datetime(2013, 1, 2)) == datetime(2013, 12, 31)
+        assert offset_n.get_year_end(datetime(2013, 1, 3)) == datetime(2013, 12, 31)
+        assert offset_n.get_year_end(datetime(2013, 1, 10)) == datetime(2013, 12, 31)
+
+        JNJ = FY5253(n=1, startingMonth=12, weekday=6, variation="nearest")
+        assert JNJ.get_year_end(datetime(2006, 1, 1)) == datetime(2006, 12, 31)
+
+    offset_lom_aug_sat = makeFY5253NearestEndMonth(
+        1, startingMonth=8, weekday=WeekDay.SAT
+    )
+    offset_lom_aug_thu = makeFY5253NearestEndMonth(
+        1, startingMonth=8, weekday=WeekDay.THU
+    )
+    offset_n = FY5253(weekday=WeekDay.TUE, startingMonth=12, variation="nearest")
+
+    on_offset_cases = [
+        #    From Wikipedia (see:
+        #    https://en.wikipedia.org/wiki/4%E2%80%934%E2%80%935_calendar
+        #    #Saturday_nearest_the_end_of_month)
+        #    2006-09-02   2006 September 2
+        #    2007-09-01   2007 September 1
+        #    2008-08-30   2008 August 30    (leap year)
+        #    2009-08-29   2009 August 29
+        #    2010-08-28   2010 August 28
+        #    2011-09-03   2011 September 3
+        #    2012-09-01   2012 September 1  (leap year)
+        #    2013-08-31   2013 August 31
+        #    2014-08-30   2014 August 30
+        #    2015-08-29   2015 August 29
+        #    2016-09-03   2016 September 3  (leap year)
+        #    2017-09-02   2017 September 2
+        #    2018-09-01   2018 September 1
+        #    2019-08-31   2019 August 31
+        (offset_lom_aug_sat, datetime(2006, 9, 2), True),
+        (offset_lom_aug_sat, datetime(2007, 9, 1), True),
+        (offset_lom_aug_sat, datetime(2008, 8, 30), True),
+        (offset_lom_aug_sat, datetime(2009, 8, 29), True),
+        (offset_lom_aug_sat, datetime(2010, 8, 28), True),
+        (offset_lom_aug_sat, datetime(2011, 9, 3), True),
+        (offset_lom_aug_sat, datetime(2016, 9, 3), True),
+        (offset_lom_aug_sat, datetime(2017, 9, 2), True),
+        (offset_lom_aug_sat, datetime(2018, 9, 1), True),
+        (offset_lom_aug_sat, datetime(2019, 8, 31), True),
+        (offset_lom_aug_sat, datetime(2006, 8, 27), False),
+        (offset_lom_aug_sat, datetime(2007, 8, 28), False),
+        (offset_lom_aug_sat, datetime(2008, 8, 31), False),
+        (offset_lom_aug_sat, datetime(2009, 8, 30), False),
+        (offset_lom_aug_sat, datetime(2010, 8, 29), False),
+        (offset_lom_aug_sat, datetime(2011, 8, 28), False),
+        (offset_lom_aug_sat, datetime(2006, 8, 25), False),
+        (offset_lom_aug_sat, datetime(2007, 8, 24), False),
+        (offset_lom_aug_sat, datetime(2008, 8, 29), False),
+        (offset_lom_aug_sat, datetime(2009, 8, 28), False),
+        (offset_lom_aug_sat, datetime(2010, 8, 27), False),
+        (offset_lom_aug_sat, datetime(2011, 8, 26), False),
+        (offset_lom_aug_sat, datetime(2019, 8, 30), False),
+        # From Micron, see:
+        # http://google.brand.edgar-online.com/?sym=MU&formtypeID=7
+        (offset_lom_aug_thu, datetime(2012, 8, 30), True),
+        (offset_lom_aug_thu, datetime(2011, 9, 1), True),
+        (offset_n, datetime(2012, 12, 31), False),
+        (offset_n, datetime(2013, 1, 1), True),
+        (offset_n, datetime(2013, 1, 2), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+    def test_apply(self):
+        date_seq_nem_8_sat = [
+            datetime(2006, 9, 2),
+            datetime(2007, 9, 1),
+            datetime(2008, 8, 30),
+            datetime(2009, 8, 29),
+            datetime(2010, 8, 28),
+            datetime(2011, 9, 3),
+        ]
+
+        JNJ = [
+            datetime(2005, 1, 2),
+            datetime(2006, 1, 1),
+            datetime(2006, 12, 31),
+            datetime(2007, 12, 30),
+            datetime(2008, 12, 28),
+            datetime(2010, 1, 3),
+            datetime(2011, 1, 2),
+            datetime(2012, 1, 1),
+            datetime(2012, 12, 30),
+        ]
+
+        DEC_SAT = FY5253(n=-1, startingMonth=12, weekday=5, variation="nearest")
+
+        tests = [
+            (
+                makeFY5253NearestEndMonth(startingMonth=8, weekday=WeekDay.SAT),
+                date_seq_nem_8_sat,
+            ),
+            (
+                makeFY5253NearestEndMonth(n=1, startingMonth=8, weekday=WeekDay.SAT),
+                date_seq_nem_8_sat,
+            ),
+            (
+                makeFY5253NearestEndMonth(startingMonth=8, weekday=WeekDay.SAT),
+                [datetime(2006, 9, 1)] + date_seq_nem_8_sat,
+            ),
+            (
+                makeFY5253NearestEndMonth(n=1, startingMonth=8, weekday=WeekDay.SAT),
+                [datetime(2006, 9, 3)] + date_seq_nem_8_sat[1:],
+            ),
+            (
+                makeFY5253NearestEndMonth(n=-1, startingMonth=8, weekday=WeekDay.SAT),
+                list(reversed(date_seq_nem_8_sat)),
+            ),
+            (
+                makeFY5253NearestEndMonth(n=1, startingMonth=12, weekday=WeekDay.SUN),
+                JNJ,
+            ),
+            (
+                makeFY5253NearestEndMonth(n=-1, startingMonth=12, weekday=WeekDay.SUN),
+                list(reversed(JNJ)),
+            ),
+            (
+                makeFY5253NearestEndMonth(n=1, startingMonth=12, weekday=WeekDay.SUN),
+                [datetime(2005, 1, 2), datetime(2006, 1, 1)],
+            ),
+            (
+                makeFY5253NearestEndMonth(n=1, startingMonth=12, weekday=WeekDay.SUN),
+                [datetime(2006, 1, 2), datetime(2006, 12, 31)],
+            ),
+            (DEC_SAT, [datetime(2013, 1, 15), datetime(2012, 12, 29)]),
+        ]
+        for test in tests:
+            offset, data = test
+            current = data[0]
+            for datum in data[1:]:
+                current = current + offset
+                assert current == datum
+
+
+class TestFY5253LastOfMonthQuarter:
+    def test_is_anchored(self):
+        msg = "FY5253Quarter.is_anchored is deprecated "
+
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            assert makeFY5253LastOfMonthQuarter(
+                startingMonth=1, weekday=WeekDay.SAT, qtr_with_extra_week=4
+            ).is_anchored()
+            assert makeFY5253LastOfMonthQuarter(
+                weekday=WeekDay.SAT, startingMonth=3, qtr_with_extra_week=4
+            ).is_anchored()
+            assert not makeFY5253LastOfMonthQuarter(
+                2, startingMonth=1, weekday=WeekDay.SAT, qtr_with_extra_week=4
+            ).is_anchored()
+
+    def test_equality(self):
+        assert makeFY5253LastOfMonthQuarter(
+            startingMonth=1, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        ) == makeFY5253LastOfMonthQuarter(
+            startingMonth=1, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+        assert makeFY5253LastOfMonthQuarter(
+            startingMonth=1, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        ) != makeFY5253LastOfMonthQuarter(
+            startingMonth=1, weekday=WeekDay.SUN, qtr_with_extra_week=4
+        )
+        assert makeFY5253LastOfMonthQuarter(
+            startingMonth=1, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        ) != makeFY5253LastOfMonthQuarter(
+            startingMonth=2, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+
+    def test_offset(self):
+        offset = makeFY5253LastOfMonthQuarter(
+            1, startingMonth=9, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+        offset2 = makeFY5253LastOfMonthQuarter(
+            2, startingMonth=9, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+        offset4 = makeFY5253LastOfMonthQuarter(
+            4, startingMonth=9, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+
+        offset_neg1 = makeFY5253LastOfMonthQuarter(
+            -1, startingMonth=9, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+        offset_neg2 = makeFY5253LastOfMonthQuarter(
+            -2, startingMonth=9, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+
+        GMCR = [
+            datetime(2010, 3, 27),
+            datetime(2010, 6, 26),
+            datetime(2010, 9, 25),
+            datetime(2010, 12, 25),
+            datetime(2011, 3, 26),
+            datetime(2011, 6, 25),
+            datetime(2011, 9, 24),
+            datetime(2011, 12, 24),
+            datetime(2012, 3, 24),
+            datetime(2012, 6, 23),
+            datetime(2012, 9, 29),
+            datetime(2012, 12, 29),
+            datetime(2013, 3, 30),
+            datetime(2013, 6, 29),
+        ]
+
+        assert_offset_equal(offset, base=GMCR[0], expected=GMCR[1])
+        assert_offset_equal(
+            offset, base=GMCR[0] + relativedelta(days=-1), expected=GMCR[0]
+        )
+        assert_offset_equal(offset, base=GMCR[1], expected=GMCR[2])
+
+        assert_offset_equal(offset2, base=GMCR[0], expected=GMCR[2])
+        assert_offset_equal(offset4, base=GMCR[0], expected=GMCR[4])
+
+        assert_offset_equal(offset_neg1, base=GMCR[-1], expected=GMCR[-2])
+        assert_offset_equal(
+            offset_neg1, base=GMCR[-1] + relativedelta(days=+1), expected=GMCR[-1]
+        )
+        assert_offset_equal(offset_neg2, base=GMCR[-1], expected=GMCR[-3])
+
+        date = GMCR[0] + relativedelta(days=-1)
+        for expected in GMCR:
+            assert_offset_equal(offset, date, expected)
+            date = date + offset
+
+        date = GMCR[-1] + relativedelta(days=+1)
+        for expected in reversed(GMCR):
+            assert_offset_equal(offset_neg1, date, expected)
+            date = date + offset_neg1
+
+    lomq_aug_sat_4 = makeFY5253LastOfMonthQuarter(
+        1, startingMonth=8, weekday=WeekDay.SAT, qtr_with_extra_week=4
+    )
+    lomq_sep_sat_4 = makeFY5253LastOfMonthQuarter(
+        1, startingMonth=9, weekday=WeekDay.SAT, qtr_with_extra_week=4
+    )
+
+    on_offset_cases = [
+        # From Wikipedia
+        (lomq_aug_sat_4, datetime(2006, 8, 26), True),
+        (lomq_aug_sat_4, datetime(2007, 8, 25), True),
+        (lomq_aug_sat_4, datetime(2008, 8, 30), True),
+        (lomq_aug_sat_4, datetime(2009, 8, 29), True),
+        (lomq_aug_sat_4, datetime(2010, 8, 28), True),
+        (lomq_aug_sat_4, datetime(2011, 8, 27), True),
+        (lomq_aug_sat_4, datetime(2019, 8, 31), True),
+        (lomq_aug_sat_4, datetime(2006, 8, 27), False),
+        (lomq_aug_sat_4, datetime(2007, 8, 28), False),
+        (lomq_aug_sat_4, datetime(2008, 8, 31), False),
+        (lomq_aug_sat_4, datetime(2009, 8, 30), False),
+        (lomq_aug_sat_4, datetime(2010, 8, 29), False),
+        (lomq_aug_sat_4, datetime(2011, 8, 28), False),
+        (lomq_aug_sat_4, datetime(2006, 8, 25), False),
+        (lomq_aug_sat_4, datetime(2007, 8, 24), False),
+        (lomq_aug_sat_4, datetime(2008, 8, 29), False),
+        (lomq_aug_sat_4, datetime(2009, 8, 28), False),
+        (lomq_aug_sat_4, datetime(2010, 8, 27), False),
+        (lomq_aug_sat_4, datetime(2011, 8, 26), False),
+        (lomq_aug_sat_4, datetime(2019, 8, 30), False),
+        # From GMCR
+        (lomq_sep_sat_4, datetime(2010, 9, 25), True),
+        (lomq_sep_sat_4, datetime(2011, 9, 24), True),
+        (lomq_sep_sat_4, datetime(2012, 9, 29), True),
+        (lomq_sep_sat_4, datetime(2013, 6, 29), True),
+        (lomq_sep_sat_4, datetime(2012, 6, 23), True),
+        (lomq_sep_sat_4, datetime(2012, 6, 30), False),
+        (lomq_sep_sat_4, datetime(2013, 3, 30), True),
+        (lomq_sep_sat_4, datetime(2012, 3, 24), True),
+        (lomq_sep_sat_4, datetime(2012, 12, 29), True),
+        (lomq_sep_sat_4, datetime(2011, 12, 24), True),
+        # INTC (extra week in Q1)
+        # See: http://www.intc.com/releasedetail.cfm?ReleaseID=542844
+        (
+            makeFY5253LastOfMonthQuarter(
+                1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+            ),
+            datetime(2011, 4, 2),
+            True,
+        ),
+        # see: http://google.brand.edgar-online.com/?sym=INTC&formtypeID=7
+        (
+            makeFY5253LastOfMonthQuarter(
+                1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+            ),
+            datetime(2012, 12, 29),
+            True,
+        ),
+        (
+            makeFY5253LastOfMonthQuarter(
+                1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+            ),
+            datetime(2011, 12, 31),
+            True,
+        ),
+        (
+            makeFY5253LastOfMonthQuarter(
+                1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+            ),
+            datetime(2010, 12, 25),
+            True,
+        ),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+    def test_year_has_extra_week(self):
+        # End of long Q1
+        assert makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        ).year_has_extra_week(datetime(2011, 4, 2))
+
+        # Start of long Q1
+        assert makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        ).year_has_extra_week(datetime(2010, 12, 26))
+
+        # End of year before year with long Q1
+        assert not makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        ).year_has_extra_week(datetime(2010, 12, 25))
+
+        for year in [
+            x for x in range(1994, 2011 + 1) if x not in [2011, 2005, 2000, 1994]
+        ]:
+            assert not makeFY5253LastOfMonthQuarter(
+                1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+            ).year_has_extra_week(datetime(year, 4, 2))
+
+        # Other long years
+        assert makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        ).year_has_extra_week(datetime(2005, 4, 2))
+
+        assert makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        ).year_has_extra_week(datetime(2000, 4, 2))
+
+        assert makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        ).year_has_extra_week(datetime(1994, 4, 2))
+
+    def test_get_weeks(self):
+        sat_dec_1 = makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=1
+        )
+        sat_dec_4 = makeFY5253LastOfMonthQuarter(
+            1, startingMonth=12, weekday=WeekDay.SAT, qtr_with_extra_week=4
+        )
+
+        assert sat_dec_1.get_weeks(datetime(2011, 4, 2)) == [14, 13, 13, 13]
+        assert sat_dec_4.get_weeks(datetime(2011, 4, 2)) == [13, 13, 13, 14]
+        assert sat_dec_1.get_weeks(datetime(2010, 12, 25)) == [13, 13, 13, 13]
+
+
+class TestFY5253NearestEndMonthQuarter:
+    offset_nem_sat_aug_4 = makeFY5253NearestEndMonthQuarter(
+        1, startingMonth=8, weekday=WeekDay.SAT, qtr_with_extra_week=4
+    )
+    offset_nem_thu_aug_4 = makeFY5253NearestEndMonthQuarter(
+        1, startingMonth=8, weekday=WeekDay.THU, qtr_with_extra_week=4
+    )
+    offset_n = FY5253(weekday=WeekDay.TUE, startingMonth=12, variation="nearest")
+
+    on_offset_cases = [
+        # From Wikipedia
+        (offset_nem_sat_aug_4, datetime(2006, 9, 2), True),
+        (offset_nem_sat_aug_4, datetime(2007, 9, 1), True),
+        (offset_nem_sat_aug_4, datetime(2008, 8, 30), True),
+        (offset_nem_sat_aug_4, datetime(2009, 8, 29), True),
+        (offset_nem_sat_aug_4, datetime(2010, 8, 28), True),
+        (offset_nem_sat_aug_4, datetime(2011, 9, 3), True),
+        (offset_nem_sat_aug_4, datetime(2016, 9, 3), True),
+        (offset_nem_sat_aug_4, datetime(2017, 9, 2), True),
+        (offset_nem_sat_aug_4, datetime(2018, 9, 1), True),
+        (offset_nem_sat_aug_4, datetime(2019, 8, 31), True),
+        (offset_nem_sat_aug_4, datetime(2006, 8, 27), False),
+        (offset_nem_sat_aug_4, datetime(2007, 8, 28), False),
+        (offset_nem_sat_aug_4, datetime(2008, 8, 31), False),
+        (offset_nem_sat_aug_4, datetime(2009, 8, 30), False),
+        (offset_nem_sat_aug_4, datetime(2010, 8, 29), False),
+        (offset_nem_sat_aug_4, datetime(2011, 8, 28), False),
+        (offset_nem_sat_aug_4, datetime(2006, 8, 25), False),
+        (offset_nem_sat_aug_4, datetime(2007, 8, 24), False),
+        (offset_nem_sat_aug_4, datetime(2008, 8, 29), False),
+        (offset_nem_sat_aug_4, datetime(2009, 8, 28), False),
+        (offset_nem_sat_aug_4, datetime(2010, 8, 27), False),
+        (offset_nem_sat_aug_4, datetime(2011, 8, 26), False),
+        (offset_nem_sat_aug_4, datetime(2019, 8, 30), False),
+        # From Micron, see:
+        # http://google.brand.edgar-online.com/?sym=MU&formtypeID=7
+        (offset_nem_thu_aug_4, datetime(2012, 8, 30), True),
+        (offset_nem_thu_aug_4, datetime(2011, 9, 1), True),
+        # See: http://google.brand.edgar-online.com/?sym=MU&formtypeID=13
+        (offset_nem_thu_aug_4, datetime(2013, 5, 30), True),
+        (offset_nem_thu_aug_4, datetime(2013, 2, 28), True),
+        (offset_nem_thu_aug_4, datetime(2012, 11, 29), True),
+        (offset_nem_thu_aug_4, datetime(2012, 5, 31), True),
+        (offset_nem_thu_aug_4, datetime(2007, 3, 1), True),
+        (offset_nem_thu_aug_4, datetime(1994, 3, 3), True),
+        (offset_n, datetime(2012, 12, 31), False),
+        (offset_n, datetime(2013, 1, 1), True),
+        (offset_n, datetime(2013, 1, 2), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+    def test_offset(self):
+        offset = makeFY5253NearestEndMonthQuarter(
+            1, startingMonth=8, weekday=WeekDay.THU, qtr_with_extra_week=4
+        )
+
+        MU = [
+            datetime(2012, 5, 31),
+            datetime(2012, 8, 30),
+            datetime(2012, 11, 29),
+            datetime(2013, 2, 28),
+            datetime(2013, 5, 30),
+        ]
+
+        date = MU[0] + relativedelta(days=-1)
+        for expected in MU:
+            assert_offset_equal(offset, date, expected)
+            date = date + offset
+
+        assert_offset_equal(offset, datetime(2012, 5, 31), datetime(2012, 8, 30))
+        assert_offset_equal(offset, datetime(2012, 5, 30), datetime(2012, 5, 31))
+
+        offset2 = FY5253Quarter(
+            weekday=5, startingMonth=12, variation="last", qtr_with_extra_week=4
+        )
+
+        assert_offset_equal(offset2, datetime(2013, 1, 15), datetime(2013, 3, 30))
+
+
+def test_bunched_yearends():
+    # GH#14774 cases with two fiscal year-ends in the same calendar-year
+    fy = FY5253(n=1, weekday=5, startingMonth=12, variation="nearest")
+    dt = Timestamp("2004-01-01")
+    assert fy.rollback(dt) == Timestamp("2002-12-28")
+    assert (-fy)._apply(dt) == Timestamp("2002-12-28")
+    assert dt - fy == Timestamp("2002-12-28")
+
+    assert fy.rollforward(dt) == Timestamp("2004-01-03")
+    assert fy._apply(dt) == Timestamp("2004-01-03")
+    assert fy + dt == Timestamp("2004-01-03")
+    assert dt + fy == Timestamp("2004-01-03")
+
+    # Same thing, but starting from a Timestamp in the previous year.
+    dt = Timestamp("2003-12-31")
+    assert fy.rollback(dt) == Timestamp("2002-12-28")
+    assert (-fy)._apply(dt) == Timestamp("2002-12-28")
+    assert dt - fy == Timestamp("2002-12-28")
+
+
+def test_fy5253_last_onoffset():
+    # GH#18877 dates on the year-end but not normalized to midnight
+    offset = FY5253(n=-5, startingMonth=5, variation="last", weekday=0)
+    ts = Timestamp("1984-05-28 06:29:43.955911354+0200", tz="Europe/San_Marino")
+    fast = offset.is_on_offset(ts)
+    slow = (ts + offset) - offset == ts
+    assert fast == slow
+
+
+def test_fy5253_nearest_onoffset():
+    # GH#18877 dates on the year-end but not normalized to midnight
+    offset = FY5253(n=3, startingMonth=7, variation="nearest", weekday=2)
+    ts = Timestamp("2032-07-28 00:12:59.035729419+0000", tz="Africa/Dakar")
+    fast = offset.is_on_offset(ts)
+    slow = (ts + offset) - offset == ts
+    assert fast == slow
+
+
+def test_fy5253qtr_onoffset_nearest():
+    # GH#19036
+    ts = Timestamp("1985-09-02 23:57:46.232550356-0300", tz="Atlantic/Bermuda")
+    offset = FY5253Quarter(
+        n=3, qtr_with_extra_week=1, startingMonth=2, variation="nearest", weekday=0
+    )
+    fast = offset.is_on_offset(ts)
+    slow = (ts + offset) - offset == ts
+    assert fast == slow
+
+
+def test_fy5253qtr_onoffset_last():
+    # GH#19036
+    offset = FY5253Quarter(
+        n=-2, qtr_with_extra_week=1, startingMonth=7, variation="last", weekday=2
+    )
+    ts = Timestamp("2011-01-26 19:03:40.331096129+0200", tz="Africa/Windhoek")
+    slow = (ts + offset) - offset == ts
+    fast = offset.is_on_offset(ts)
+    assert fast == slow

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_index.py

@@ -0,0 +1,57 @@
+"""
+Tests for offset behavior with indices.
+"""
+import pytest
+
+from pandas import (
+    Series,
+    date_range,
+)
+
+from pandas.tseries.offsets import (
+    BMonthBegin,
+    BMonthEnd,
+    BQuarterBegin,
+    BQuarterEnd,
+    BYearBegin,
+    BYearEnd,
+    MonthBegin,
+    MonthEnd,
+    QuarterBegin,
+    QuarterEnd,
+    YearBegin,
+    YearEnd,
+)
+
+
+@pytest.mark.parametrize("n", [-2, 1])
+@pytest.mark.parametrize(
+    "cls",
+    [
+        MonthBegin,
+        MonthEnd,
+        BMonthBegin,
+        BMonthEnd,
+        QuarterBegin,
+        QuarterEnd,
+        BQuarterBegin,
+        BQuarterEnd,
+        YearBegin,
+        YearEnd,
+        BYearBegin,
+        BYearEnd,
+    ],
+)
+def test_apply_index(cls, n):
+    offset = cls(n=n)
+    rng = date_range(start="1/1/2000", periods=100000, freq="min")
+    ser = Series(rng)
+
+    res = rng + offset
+    assert res.freq is None  # not retained
+    assert res[0] == rng[0] + offset
+    assert res[-1] == rng[-1] + offset
+    res2 = ser + offset
+    # apply_index is only for indexes, not series, so no res2_v2
+    assert res2.iloc[0] == ser.iloc[0] + offset
+    assert res2.iloc[-1] == ser.iloc[-1] + offset

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_month.py

@@ -0,0 +1,666 @@
+"""
+Tests for the following offsets:
+- SemiMonthBegin
+- SemiMonthEnd
+- MonthBegin
+- MonthEnd
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+
+from pandas._libs.tslibs import Timestamp
+from pandas._libs.tslibs.offsets import (
+    MonthBegin,
+    MonthEnd,
+    SemiMonthBegin,
+    SemiMonthEnd,
+)
+
+from pandas import (
+    DatetimeIndex,
+    Series,
+    _testing as tm,
+)
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+
+class TestSemiMonthEnd:
+    def test_offset_whole_year(self):
+        dates = (
+            datetime(2007, 12, 31),
+            datetime(2008, 1, 15),
+            datetime(2008, 1, 31),
+            datetime(2008, 2, 15),
+            datetime(2008, 2, 29),
+            datetime(2008, 3, 15),
+            datetime(2008, 3, 31),
+            datetime(2008, 4, 15),
+            datetime(2008, 4, 30),
+            datetime(2008, 5, 15),
+            datetime(2008, 5, 31),
+            datetime(2008, 6, 15),
+            datetime(2008, 6, 30),
+            datetime(2008, 7, 15),
+            datetime(2008, 7, 31),
+            datetime(2008, 8, 15),
+            datetime(2008, 8, 31),
+            datetime(2008, 9, 15),
+            datetime(2008, 9, 30),
+            datetime(2008, 10, 15),
+            datetime(2008, 10, 31),
+            datetime(2008, 11, 15),
+            datetime(2008, 11, 30),
+            datetime(2008, 12, 15),
+            datetime(2008, 12, 31),
+        )
+
+        for base, exp_date in zip(dates[:-1], dates[1:]):
+            assert_offset_equal(SemiMonthEnd(), base, exp_date)
+
+        # ensure .apply_index works as expected
+        shift = DatetimeIndex(dates[:-1])
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = SemiMonthEnd() + shift
+
+        exp = DatetimeIndex(dates[1:])
+        tm.assert_index_equal(result, exp)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            SemiMonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 15),
+                datetime(2008, 1, 15): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 2, 15),
+                datetime(2006, 12, 14): datetime(2006, 12, 15),
+                datetime(2006, 12, 29): datetime(2006, 12, 31),
+                datetime(2006, 12, 31): datetime(2007, 1, 15),
+                datetime(2007, 1, 1): datetime(2007, 1, 15),
+                datetime(2006, 12, 1): datetime(2006, 12, 15),
+                datetime(2006, 12, 15): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(day_of_month=20),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 20),
+                datetime(2008, 1, 15): datetime(2008, 1, 20),
+                datetime(2008, 1, 21): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 2, 20),
+                datetime(2006, 12, 14): datetime(2006, 12, 20),
+                datetime(2006, 12, 29): datetime(2006, 12, 31),
+                datetime(2006, 12, 31): datetime(2007, 1, 20),
+                datetime(2007, 1, 1): datetime(2007, 1, 20),
+                datetime(2006, 12, 1): datetime(2006, 12, 20),
+                datetime(2006, 12, 15): datetime(2006, 12, 20),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 15),
+                datetime(2008, 1, 16): datetime(2008, 1, 31),
+                datetime(2008, 1, 15): datetime(2008, 1, 15),
+                datetime(2008, 1, 31): datetime(2008, 1, 31),
+                datetime(2006, 12, 29): datetime(2006, 12, 31),
+                datetime(2006, 12, 31): datetime(2006, 12, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 15),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(0, day_of_month=16),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 16),
+                datetime(2008, 1, 16): datetime(2008, 1, 16),
+                datetime(2008, 1, 15): datetime(2008, 1, 16),
+                datetime(2008, 1, 31): datetime(2008, 1, 31),
+                datetime(2006, 12, 29): datetime(2006, 12, 31),
+                datetime(2006, 12, 31): datetime(2006, 12, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 16),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 2, 29),
+                datetime(2006, 12, 29): datetime(2007, 1, 15),
+                datetime(2006, 12, 31): datetime(2007, 1, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 31),
+                datetime(2007, 1, 16): datetime(2007, 2, 15),
+                datetime(2006, 11, 1): datetime(2006, 11, 30),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 6, 15),
+                datetime(2008, 12, 31): datetime(2008, 12, 15),
+                datetime(2006, 12, 29): datetime(2006, 12, 15),
+                datetime(2006, 12, 30): datetime(2006, 12, 15),
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(-1, day_of_month=4),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+                datetime(2007, 1, 4): datetime(2006, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 6, 4),
+                datetime(2008, 12, 31): datetime(2008, 12, 4),
+                datetime(2006, 12, 5): datetime(2006, 12, 4),
+                datetime(2006, 12, 30): datetime(2006, 12, 4),
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            SemiMonthEnd(-2),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 15),
+                datetime(2008, 6, 30): datetime(2008, 5, 31),
+                datetime(2008, 3, 15): datetime(2008, 2, 15),
+                datetime(2008, 12, 31): datetime(2008, 11, 30),
+                datetime(2006, 12, 29): datetime(2006, 11, 30),
+                datetime(2006, 12, 14): datetime(2006, 11, 15),
+                datetime(2007, 1, 1): datetime(2006, 12, 15),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_apply_index(self, case):
+        # https://github.com/pandas-dev/pandas/issues/34580
+        offset, cases = case
+        shift = DatetimeIndex(cases.keys())
+        exp = DatetimeIndex(cases.values())
+
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = offset + shift
+        tm.assert_index_equal(result, exp)
+
+    on_offset_cases = [
+        (datetime(2007, 12, 31), True),
+        (datetime(2007, 12, 15), True),
+        (datetime(2007, 12, 14), False),
+        (datetime(2007, 12, 1), False),
+        (datetime(2008, 2, 29), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        dt, expected = case
+        assert_is_on_offset(SemiMonthEnd(), dt, expected)
+
+    @pytest.mark.parametrize("klass", [Series, DatetimeIndex])
+    def test_vectorized_offset_addition(self, klass):
+        shift = klass(
+            [
+                Timestamp("2000-01-15 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-15", tz="US/Central"),
+            ],
+            name="a",
+        )
+
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = shift + SemiMonthEnd()
+            result2 = SemiMonthEnd() + shift
+
+        exp = klass(
+            [
+                Timestamp("2000-01-31 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-29", tz="US/Central"),
+            ],
+            name="a",
+        )
+        tm.assert_equal(result, exp)
+        tm.assert_equal(result2, exp)
+
+        shift = klass(
+            [
+                Timestamp("2000-01-01 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-01", tz="US/Central"),
+            ],
+            name="a",
+        )
+
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = shift + SemiMonthEnd()
+            result2 = SemiMonthEnd() + shift
+
+        exp = klass(
+            [
+                Timestamp("2000-01-15 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-15", tz="US/Central"),
+            ],
+            name="a",
+        )
+        tm.assert_equal(result, exp)
+        tm.assert_equal(result2, exp)
+
+
+class TestSemiMonthBegin:
+    def test_offset_whole_year(self):
+        dates = (
+            datetime(2007, 12, 15),
+            datetime(2008, 1, 1),
+            datetime(2008, 1, 15),
+            datetime(2008, 2, 1),
+            datetime(2008, 2, 15),
+            datetime(2008, 3, 1),
+            datetime(2008, 3, 15),
+            datetime(2008, 4, 1),
+            datetime(2008, 4, 15),
+            datetime(2008, 5, 1),
+            datetime(2008, 5, 15),
+            datetime(2008, 6, 1),
+            datetime(2008, 6, 15),
+            datetime(2008, 7, 1),
+            datetime(2008, 7, 15),
+            datetime(2008, 8, 1),
+            datetime(2008, 8, 15),
+            datetime(2008, 9, 1),
+            datetime(2008, 9, 15),
+            datetime(2008, 10, 1),
+            datetime(2008, 10, 15),
+            datetime(2008, 11, 1),
+            datetime(2008, 11, 15),
+            datetime(2008, 12, 1),
+            datetime(2008, 12, 15),
+        )
+
+        for base, exp_date in zip(dates[:-1], dates[1:]):
+            assert_offset_equal(SemiMonthBegin(), base, exp_date)
+
+        # ensure .apply_index works as expected
+        shift = DatetimeIndex(dates[:-1])
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = SemiMonthBegin() + shift
+
+        exp = DatetimeIndex(dates[1:])
+        tm.assert_index_equal(result, exp)
+
+    offset_cases = [
+        (
+            SemiMonthBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 15),
+                datetime(2008, 1, 15): datetime(2008, 2, 1),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2006, 12, 14): datetime(2006, 12, 15),
+                datetime(2006, 12, 29): datetime(2007, 1, 1),
+                datetime(2006, 12, 31): datetime(2007, 1, 1),
+                datetime(2007, 1, 1): datetime(2007, 1, 15),
+                datetime(2006, 12, 1): datetime(2006, 12, 15),
+                datetime(2006, 12, 15): datetime(2007, 1, 1),
+            },
+        ),
+        (
+            SemiMonthBegin(day_of_month=20),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 20),
+                datetime(2008, 1, 15): datetime(2008, 1, 20),
+                datetime(2008, 1, 21): datetime(2008, 2, 1),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2006, 12, 14): datetime(2006, 12, 20),
+                datetime(2006, 12, 29): datetime(2007, 1, 1),
+                datetime(2006, 12, 31): datetime(2007, 1, 1),
+                datetime(2007, 1, 1): datetime(2007, 1, 20),
+                datetime(2006, 12, 1): datetime(2006, 12, 20),
+                datetime(2006, 12, 15): datetime(2006, 12, 20),
+            },
+        ),
+        (
+            SemiMonthBegin(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 1, 16): datetime(2008, 2, 1),
+                datetime(2008, 1, 15): datetime(2008, 1, 15),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2006, 12, 29): datetime(2007, 1, 1),
+                datetime(2006, 12, 2): datetime(2006, 12, 15),
+                datetime(2007, 1, 1): datetime(2007, 1, 1),
+            },
+        ),
+        (
+            SemiMonthBegin(0, day_of_month=16),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 1, 16): datetime(2008, 1, 16),
+                datetime(2008, 1, 15): datetime(2008, 1, 16),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2006, 12, 29): datetime(2007, 1, 1),
+                datetime(2006, 12, 31): datetime(2007, 1, 1),
+                datetime(2007, 1, 5): datetime(2007, 1, 16),
+                datetime(2007, 1, 1): datetime(2007, 1, 1),
+            },
+        ),
+        (
+            SemiMonthBegin(2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 1),
+                datetime(2008, 1, 31): datetime(2008, 2, 15),
+                datetime(2006, 12, 1): datetime(2007, 1, 1),
+                datetime(2006, 12, 29): datetime(2007, 1, 15),
+                datetime(2006, 12, 15): datetime(2007, 1, 15),
+                datetime(2007, 1, 1): datetime(2007, 2, 1),
+                datetime(2007, 1, 16): datetime(2007, 2, 15),
+                datetime(2006, 11, 1): datetime(2006, 12, 1),
+            },
+        ),
+        (
+            SemiMonthBegin(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 15),
+                datetime(2008, 6, 30): datetime(2008, 6, 15),
+                datetime(2008, 6, 14): datetime(2008, 6, 1),
+                datetime(2008, 12, 31): datetime(2008, 12, 15),
+                datetime(2006, 12, 29): datetime(2006, 12, 15),
+                datetime(2006, 12, 15): datetime(2006, 12, 1),
+                datetime(2007, 1, 1): datetime(2006, 12, 15),
+            },
+        ),
+        (
+            SemiMonthBegin(-1, day_of_month=4),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 4),
+                datetime(2007, 1, 4): datetime(2007, 1, 1),
+                datetime(2008, 6, 30): datetime(2008, 6, 4),
+                datetime(2008, 12, 31): datetime(2008, 12, 4),
+                datetime(2006, 12, 5): datetime(2006, 12, 4),
+                datetime(2006, 12, 30): datetime(2006, 12, 4),
+                datetime(2006, 12, 2): datetime(2006, 12, 1),
+                datetime(2007, 1, 1): datetime(2006, 12, 4),
+            },
+        ),
+        (
+            SemiMonthBegin(-2),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 1),
+                datetime(2008, 6, 30): datetime(2008, 6, 1),
+                datetime(2008, 6, 14): datetime(2008, 5, 15),
+                datetime(2008, 12, 31): datetime(2008, 12, 1),
+                datetime(2006, 12, 29): datetime(2006, 12, 1),
+                datetime(2006, 12, 15): datetime(2006, 11, 15),
+                datetime(2007, 1, 1): datetime(2006, 12, 1),
+            },
+        ),
+    ]
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_apply_index(self, case):
+        offset, cases = case
+        shift = DatetimeIndex(cases.keys())
+
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = offset + shift
+
+        exp = DatetimeIndex(cases.values())
+        tm.assert_index_equal(result, exp)
+
+    on_offset_cases = [
+        (datetime(2007, 12, 1), True),
+        (datetime(2007, 12, 15), True),
+        (datetime(2007, 12, 14), False),
+        (datetime(2007, 12, 31), False),
+        (datetime(2008, 2, 15), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        dt, expected = case
+        assert_is_on_offset(SemiMonthBegin(), dt, expected)
+
+    @pytest.mark.parametrize("klass", [Series, DatetimeIndex])
+    def test_vectorized_offset_addition(self, klass):
+        shift = klass(
+            [
+                Timestamp("2000-01-15 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-15", tz="US/Central"),
+            ],
+            name="a",
+        )
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = shift + SemiMonthBegin()
+            result2 = SemiMonthBegin() + shift
+
+        exp = klass(
+            [
+                Timestamp("2000-02-01 00:15:00", tz="US/Central"),
+                Timestamp("2000-03-01", tz="US/Central"),
+            ],
+            name="a",
+        )
+        tm.assert_equal(result, exp)
+        tm.assert_equal(result2, exp)
+
+        shift = klass(
+            [
+                Timestamp("2000-01-01 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-01", tz="US/Central"),
+            ],
+            name="a",
+        )
+        with tm.assert_produces_warning(None):
+            # GH#22535 check that we don't get a FutureWarning from adding
+            # an integer array to PeriodIndex
+            result = shift + SemiMonthBegin()
+            result2 = SemiMonthBegin() + shift
+
+        exp = klass(
+            [
+                Timestamp("2000-01-15 00:15:00", tz="US/Central"),
+                Timestamp("2000-02-15", tz="US/Central"),
+            ],
+            name="a",
+        )
+        tm.assert_equal(result, exp)
+        tm.assert_equal(result2, exp)
+
+
+class TestMonthBegin:
+    offset_cases = []
+    # NOTE: I'm not entirely happy with the logic here for Begin -ss
+    # see thread 'offset conventions' on the ML
+    offset_cases.append(
+        (
+            MonthBegin(),
+            {
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2008, 2, 1): datetime(2008, 3, 1),
+                datetime(2006, 12, 31): datetime(2007, 1, 1),
+                datetime(2006, 12, 1): datetime(2007, 1, 1),
+                datetime(2007, 1, 31): datetime(2007, 2, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            MonthBegin(0),
+            {
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2006, 12, 3): datetime(2007, 1, 1),
+                datetime(2007, 1, 31): datetime(2007, 2, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            MonthBegin(2),
+            {
+                datetime(2008, 2, 29): datetime(2008, 4, 1),
+                datetime(2008, 1, 31): datetime(2008, 3, 1),
+                datetime(2006, 12, 31): datetime(2007, 2, 1),
+                datetime(2007, 12, 28): datetime(2008, 2, 1),
+                datetime(2007, 1, 1): datetime(2007, 3, 1),
+                datetime(2006, 11, 1): datetime(2007, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            MonthBegin(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 1),
+                datetime(2008, 5, 31): datetime(2008, 5, 1),
+                datetime(2008, 12, 31): datetime(2008, 12, 1),
+                datetime(2006, 12, 29): datetime(2006, 12, 1),
+                datetime(2006, 1, 2): datetime(2006, 1, 1),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+
+class TestMonthEnd:
+    def test_day_of_month(self):
+        dt = datetime(2007, 1, 1)
+        offset = MonthEnd()
+
+        result = dt + offset
+        assert result == Timestamp(2007, 1, 31)
+
+        result = result + offset
+        assert result == Timestamp(2007, 2, 28)
+
+    def test_normalize(self):
+        dt = datetime(2007, 1, 1, 3)
+
+        result = dt + MonthEnd(normalize=True)
+        expected = dt.replace(hour=0) + MonthEnd()
+        assert result == expected
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            MonthEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 2, 29),
+                datetime(2006, 12, 29): datetime(2006, 12, 31),
+                datetime(2006, 12, 31): datetime(2007, 1, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 31),
+                datetime(2006, 12, 1): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            MonthEnd(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 1, 31),
+                datetime(2006, 12, 29): datetime(2006, 12, 31),
+                datetime(2006, 12, 31): datetime(2006, 12, 31),
+                datetime(2007, 1, 1): datetime(2007, 1, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            MonthEnd(2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 29),
+                datetime(2008, 1, 31): datetime(2008, 3, 31),
+                datetime(2006, 12, 29): datetime(2007, 1, 31),
+                datetime(2006, 12, 31): datetime(2007, 2, 28),
+                datetime(2007, 1, 1): datetime(2007, 2, 28),
+                datetime(2006, 11, 1): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            MonthEnd(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 5, 31),
+                datetime(2008, 12, 31): datetime(2008, 11, 30),
+                datetime(2006, 12, 29): datetime(2006, 11, 30),
+                datetime(2006, 12, 30): datetime(2006, 11, 30),
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (MonthEnd(), datetime(2007, 12, 31), True),
+        (MonthEnd(), datetime(2008, 1, 1), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_offsets_properties.py

@@ -0,0 +1,60 @@
+"""
+Behavioral based tests for offsets and date_range.
+
+This file is adapted from https://github.com/pandas-dev/pandas/pull/18761 -
+which was more ambitious but less idiomatic in its use of Hypothesis.
+
+You may wish to consult the previous version for inspiration on further
+tests, or when trying to pin down the bugs exposed by the tests below.
+"""
+from hypothesis import (
+    assume,
+    given,
+)
+import pytest
+import pytz
+
+import pandas as pd
+from pandas._testing._hypothesis import (
+    DATETIME_JAN_1_1900_OPTIONAL_TZ,
+    YQM_OFFSET,
+)
+
+# ----------------------------------------------------------------
+# Offset-specific behaviour tests
+
+
+@pytest.mark.arm_slow
+@given(DATETIME_JAN_1_1900_OPTIONAL_TZ, YQM_OFFSET)
+def test_on_offset_implementations(dt, offset):
+    assume(not offset.normalize)
+    # check that the class-specific implementations of is_on_offset match
+    # the general case definition:
+    #   (dt + offset) - offset == dt
+    try:
+        compare = (dt + offset) - offset
+    except (pytz.NonExistentTimeError, pytz.AmbiguousTimeError):
+        # When dt + offset does not exist or is DST-ambiguous, assume(False) to
+        # indicate to hypothesis that this is not a valid test case
+        # DST-ambiguous example (GH41906):
+        # dt = datetime.datetime(1900, 1, 1, tzinfo=pytz.timezone('Africa/Kinshasa'))
+        # offset = MonthBegin(66)
+        assume(False)
+
+    assert offset.is_on_offset(dt) == (compare == dt)
+
+
+@given(YQM_OFFSET)
+def test_shift_across_dst(offset):
+    # GH#18319 check that 1) timezone is correctly normalized and
+    # 2) that hour is not incorrectly changed by this normalization
+    assume(not offset.normalize)
+
+    # Note that dti includes a transition across DST boundary
+    dti = pd.date_range(
+        start="2017-10-30 12:00:00", end="2017-11-06", freq="D", tz="US/Eastern"
+    )
+    assert (dti.hour == 12).all()  # we haven't screwed up yet
+
+    res = dti + offset
+    assert (res.hour == 12).all()

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_quarter.py

@@ -0,0 +1,303 @@
+"""
+Tests for the following offsets:
+- QuarterBegin
+- QuarterEnd
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+
+import pandas._testing as tm
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries.offsets import (
+    QuarterBegin,
+    QuarterEnd,
+)
+
+
+@pytest.mark.parametrize("klass", (QuarterBegin, QuarterEnd))
+def test_quarterly_dont_normalize(klass):
+    date = datetime(2012, 3, 31, 5, 30)
+    result = date + klass()
+    assert result.time() == date.time()
+
+
+@pytest.mark.parametrize("offset", [QuarterBegin(), QuarterEnd()])
+@pytest.mark.parametrize(
+    "date",
+    [
+        datetime(2016, m, d)
+        for m in [10, 11, 12]
+        for d in [1, 2, 3, 28, 29, 30, 31]
+        if not (m == 11 and d == 31)
+    ],
+)
+def test_on_offset(offset, date):
+    res = offset.is_on_offset(date)
+    slow_version = date == (date + offset) - offset
+    assert res == slow_version
+
+
+class TestQuarterBegin:
+    def test_repr(self):
+        expected = "<QuarterBegin: startingMonth=3>"
+        assert repr(QuarterBegin()) == expected
+        expected = "<QuarterBegin: startingMonth=3>"
+        assert repr(QuarterBegin(startingMonth=3)) == expected
+        expected = "<QuarterBegin: startingMonth=1>"
+        assert repr(QuarterBegin(startingMonth=1)) == expected
+
+    def test_is_anchored(self):
+        msg = "QuarterBegin.is_anchored is deprecated "
+
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            assert QuarterBegin(startingMonth=1).is_anchored()
+            assert QuarterBegin().is_anchored()
+            assert not QuarterBegin(2, startingMonth=1).is_anchored()
+
+    def test_offset_corner_case(self):
+        # corner
+        offset = QuarterBegin(n=-1, startingMonth=1)
+        assert datetime(2010, 2, 1) + offset == datetime(2010, 1, 1)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            QuarterBegin(startingMonth=1),
+            {
+                datetime(2007, 12, 1): datetime(2008, 1, 1),
+                datetime(2008, 1, 1): datetime(2008, 4, 1),
+                datetime(2008, 2, 15): datetime(2008, 4, 1),
+                datetime(2008, 2, 29): datetime(2008, 4, 1),
+                datetime(2008, 3, 15): datetime(2008, 4, 1),
+                datetime(2008, 3, 31): datetime(2008, 4, 1),
+                datetime(2008, 4, 15): datetime(2008, 7, 1),
+                datetime(2008, 4, 1): datetime(2008, 7, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterBegin(startingMonth=2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 1),
+                datetime(2008, 1, 31): datetime(2008, 2, 1),
+                datetime(2008, 1, 15): datetime(2008, 2, 1),
+                datetime(2008, 2, 29): datetime(2008, 5, 1),
+                datetime(2008, 3, 15): datetime(2008, 5, 1),
+                datetime(2008, 3, 31): datetime(2008, 5, 1),
+                datetime(2008, 4, 15): datetime(2008, 5, 1),
+                datetime(2008, 4, 30): datetime(2008, 5, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterBegin(startingMonth=1, n=0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 12, 1): datetime(2009, 1, 1),
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 2, 15): datetime(2008, 4, 1),
+                datetime(2008, 2, 29): datetime(2008, 4, 1),
+                datetime(2008, 3, 15): datetime(2008, 4, 1),
+                datetime(2008, 3, 31): datetime(2008, 4, 1),
+                datetime(2008, 4, 15): datetime(2008, 7, 1),
+                datetime(2008, 4, 30): datetime(2008, 7, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterBegin(startingMonth=1, n=-1),
+            {
+                datetime(2008, 1, 1): datetime(2007, 10, 1),
+                datetime(2008, 1, 31): datetime(2008, 1, 1),
+                datetime(2008, 2, 15): datetime(2008, 1, 1),
+                datetime(2008, 2, 29): datetime(2008, 1, 1),
+                datetime(2008, 3, 15): datetime(2008, 1, 1),
+                datetime(2008, 3, 31): datetime(2008, 1, 1),
+                datetime(2008, 4, 15): datetime(2008, 4, 1),
+                datetime(2008, 4, 30): datetime(2008, 4, 1),
+                datetime(2008, 7, 1): datetime(2008, 4, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterBegin(startingMonth=1, n=2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 7, 1),
+                datetime(2008, 2, 15): datetime(2008, 7, 1),
+                datetime(2008, 2, 29): datetime(2008, 7, 1),
+                datetime(2008, 3, 15): datetime(2008, 7, 1),
+                datetime(2008, 3, 31): datetime(2008, 7, 1),
+                datetime(2008, 4, 15): datetime(2008, 10, 1),
+                datetime(2008, 4, 1): datetime(2008, 10, 1),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+
+class TestQuarterEnd:
+    def test_repr(self):
+        expected = "<QuarterEnd: startingMonth=3>"
+        assert repr(QuarterEnd()) == expected
+        expected = "<QuarterEnd: startingMonth=3>"
+        assert repr(QuarterEnd(startingMonth=3)) == expected
+        expected = "<QuarterEnd: startingMonth=1>"
+        assert repr(QuarterEnd(startingMonth=1)) == expected
+
+    def test_is_anchored(self):
+        msg = "QuarterEnd.is_anchored is deprecated "
+
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            assert QuarterEnd(startingMonth=1).is_anchored()
+            assert QuarterEnd().is_anchored()
+            assert not QuarterEnd(2, startingMonth=1).is_anchored()
+
+    def test_offset_corner_case(self):
+        # corner
+        offset = QuarterEnd(n=-1, startingMonth=1)
+        assert datetime(2010, 2, 1) + offset == datetime(2010, 1, 31)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            QuarterEnd(startingMonth=1),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 4, 30),
+                datetime(2008, 2, 15): datetime(2008, 4, 30),
+                datetime(2008, 2, 29): datetime(2008, 4, 30),
+                datetime(2008, 3, 15): datetime(2008, 4, 30),
+                datetime(2008, 3, 31): datetime(2008, 4, 30),
+                datetime(2008, 4, 15): datetime(2008, 4, 30),
+                datetime(2008, 4, 30): datetime(2008, 7, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterEnd(startingMonth=2),
+            {
+                datetime(2008, 1, 1): datetime(2008, 2, 29),
+                datetime(2008, 1, 31): datetime(2008, 2, 29),
+                datetime(2008, 2, 15): datetime(2008, 2, 29),
+                datetime(2008, 2, 29): datetime(2008, 5, 31),
+                datetime(2008, 3, 15): datetime(2008, 5, 31),
+                datetime(2008, 3, 31): datetime(2008, 5, 31),
+                datetime(2008, 4, 15): datetime(2008, 5, 31),
+                datetime(2008, 4, 30): datetime(2008, 5, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterEnd(startingMonth=1, n=0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 31),
+                datetime(2008, 1, 31): datetime(2008, 1, 31),
+                datetime(2008, 2, 15): datetime(2008, 4, 30),
+                datetime(2008, 2, 29): datetime(2008, 4, 30),
+                datetime(2008, 3, 15): datetime(2008, 4, 30),
+                datetime(2008, 3, 31): datetime(2008, 4, 30),
+                datetime(2008, 4, 15): datetime(2008, 4, 30),
+                datetime(2008, 4, 30): datetime(2008, 4, 30),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterEnd(startingMonth=1, n=-1),
+            {
+                datetime(2008, 1, 1): datetime(2007, 10, 31),
+                datetime(2008, 1, 31): datetime(2007, 10, 31),
+                datetime(2008, 2, 15): datetime(2008, 1, 31),
+                datetime(2008, 2, 29): datetime(2008, 1, 31),
+                datetime(2008, 3, 15): datetime(2008, 1, 31),
+                datetime(2008, 3, 31): datetime(2008, 1, 31),
+                datetime(2008, 4, 15): datetime(2008, 1, 31),
+                datetime(2008, 4, 30): datetime(2008, 1, 31),
+                datetime(2008, 7, 1): datetime(2008, 4, 30),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            QuarterEnd(startingMonth=1, n=2),
+            {
+                datetime(2008, 1, 31): datetime(2008, 7, 31),
+                datetime(2008, 2, 15): datetime(2008, 7, 31),
+                datetime(2008, 2, 29): datetime(2008, 7, 31),
+                datetime(2008, 3, 15): datetime(2008, 7, 31),
+                datetime(2008, 3, 31): datetime(2008, 7, 31),
+                datetime(2008, 4, 15): datetime(2008, 7, 31),
+                datetime(2008, 4, 30): datetime(2008, 10, 31),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (QuarterEnd(1, startingMonth=1), datetime(2008, 1, 31), True),
+        (QuarterEnd(1, startingMonth=1), datetime(2007, 12, 31), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2008, 2, 29), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2007, 3, 30), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2007, 3, 31), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2008, 4, 30), True),
+        (QuarterEnd(1, startingMonth=1), datetime(2008, 5, 30), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2008, 5, 31), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2007, 6, 29), False),
+        (QuarterEnd(1, startingMonth=1), datetime(2007, 6, 30), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2008, 1, 31), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2007, 12, 31), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2008, 2, 29), True),
+        (QuarterEnd(1, startingMonth=2), datetime(2007, 3, 30), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2007, 3, 31), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2008, 4, 30), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2008, 5, 30), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2008, 5, 31), True),
+        (QuarterEnd(1, startingMonth=2), datetime(2007, 6, 29), False),
+        (QuarterEnd(1, startingMonth=2), datetime(2007, 6, 30), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2008, 1, 31), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2007, 12, 31), True),
+        (QuarterEnd(1, startingMonth=3), datetime(2008, 2, 29), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2007, 3, 30), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2007, 3, 31), True),
+        (QuarterEnd(1, startingMonth=3), datetime(2008, 4, 30), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2008, 5, 30), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2008, 5, 31), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2007, 6, 29), False),
+        (QuarterEnd(1, startingMonth=3), datetime(2007, 6, 30), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_ticks.py

@@ -0,0 +1,405 @@
+"""
+Tests for offsets.Tick and subclasses
+"""
+from datetime import (
+    datetime,
+    timedelta,
+)
+
+from hypothesis import (
+    assume,
+    example,
+    given,
+)
+import numpy as np
+import pytest
+
+from pandas._libs.tslibs.offsets import delta_to_tick
+from pandas.errors import OutOfBoundsTimedelta
+
+from pandas import (
+    Timedelta,
+    Timestamp,
+)
+import pandas._testing as tm
+from pandas._testing._hypothesis import INT_NEG_999_TO_POS_999
+from pandas.tests.tseries.offsets.common import assert_offset_equal
+
+from pandas.tseries import offsets
+from pandas.tseries.offsets import (
+    Hour,
+    Micro,
+    Milli,
+    Minute,
+    Nano,
+    Second,
+)
+
+# ---------------------------------------------------------------------
+# Test Helpers
+
+tick_classes = [Hour, Minute, Second, Milli, Micro, Nano]
+
+
+# ---------------------------------------------------------------------
+
+
+def test_apply_ticks():
+    result = offsets.Hour(3) + offsets.Hour(4)
+    exp = offsets.Hour(7)
+    assert result == exp
+
+
+def test_delta_to_tick():
+    delta = timedelta(3)
+
+    tick = delta_to_tick(delta)
+    assert tick == offsets.Day(3)
+
+    td = Timedelta(nanoseconds=5)
+    tick = delta_to_tick(td)
+    assert tick == Nano(5)
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+@example(n=2, m=3)
+@example(n=800, m=300)
+@example(n=1000, m=5)
+@given(n=INT_NEG_999_TO_POS_999, m=INT_NEG_999_TO_POS_999)
+def test_tick_add_sub(cls, n, m):
+    # For all Tick subclasses and all integers n, m, we should have
+    # tick(n) + tick(m) == tick(n+m)
+    # tick(n) - tick(m) == tick(n-m)
+    left = cls(n)
+    right = cls(m)
+    expected = cls(n + m)
+
+    assert left + right == expected
+
+    expected = cls(n - m)
+    assert left - right == expected
+
+
+@pytest.mark.arm_slow
+@pytest.mark.parametrize("cls", tick_classes)
+@example(n=2, m=3)
+@given(n=INT_NEG_999_TO_POS_999, m=INT_NEG_999_TO_POS_999)
+def test_tick_equality(cls, n, m):
+    assume(m != n)
+    # tick == tock iff tick.n == tock.n
+    left = cls(n)
+    right = cls(m)
+    assert left != right
+
+    right = cls(n)
+    assert left == right
+    assert not left != right
+
+    if n != 0:
+        assert cls(n) != cls(-n)
+
+
+# ---------------------------------------------------------------------
+
+
+def test_Hour():
+    assert_offset_equal(Hour(), datetime(2010, 1, 1), datetime(2010, 1, 1, 1))
+    assert_offset_equal(Hour(-1), datetime(2010, 1, 1, 1), datetime(2010, 1, 1))
+    assert_offset_equal(2 * Hour(), datetime(2010, 1, 1), datetime(2010, 1, 1, 2))
+    assert_offset_equal(-1 * Hour(), datetime(2010, 1, 1, 1), datetime(2010, 1, 1))
+
+    assert Hour(3) + Hour(2) == Hour(5)
+    assert Hour(3) - Hour(2) == Hour()
+
+    assert Hour(4) != Hour(1)
+
+
+def test_Minute():
+    assert_offset_equal(Minute(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 1))
+    assert_offset_equal(Minute(-1), datetime(2010, 1, 1, 0, 1), datetime(2010, 1, 1))
+    assert_offset_equal(2 * Minute(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 2))
+    assert_offset_equal(-1 * Minute(), datetime(2010, 1, 1, 0, 1), datetime(2010, 1, 1))
+
+    assert Minute(3) + Minute(2) == Minute(5)
+    assert Minute(3) - Minute(2) == Minute()
+    assert Minute(5) != Minute()
+
+
+def test_Second():
+    assert_offset_equal(Second(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 1))
+    assert_offset_equal(Second(-1), datetime(2010, 1, 1, 0, 0, 1), datetime(2010, 1, 1))
+    assert_offset_equal(
+        2 * Second(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 2)
+    )
+    assert_offset_equal(
+        -1 * Second(), datetime(2010, 1, 1, 0, 0, 1), datetime(2010, 1, 1)
+    )
+
+    assert Second(3) + Second(2) == Second(5)
+    assert Second(3) - Second(2) == Second()
+
+
+def test_Millisecond():
+    assert_offset_equal(
+        Milli(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 0, 1000)
+    )
+    assert_offset_equal(
+        Milli(-1), datetime(2010, 1, 1, 0, 0, 0, 1000), datetime(2010, 1, 1)
+    )
+    assert_offset_equal(
+        Milli(2), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 0, 2000)
+    )
+    assert_offset_equal(
+        2 * Milli(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 0, 2000)
+    )
+    assert_offset_equal(
+        -1 * Milli(), datetime(2010, 1, 1, 0, 0, 0, 1000), datetime(2010, 1, 1)
+    )
+
+    assert Milli(3) + Milli(2) == Milli(5)
+    assert Milli(3) - Milli(2) == Milli()
+
+
+def test_MillisecondTimestampArithmetic():
+    assert_offset_equal(
+        Milli(), Timestamp("2010-01-01"), Timestamp("2010-01-01 00:00:00.001")
+    )
+    assert_offset_equal(
+        Milli(-1), Timestamp("2010-01-01 00:00:00.001"), Timestamp("2010-01-01")
+    )
+
+
+def test_Microsecond():
+    assert_offset_equal(Micro(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 0, 1))
+    assert_offset_equal(
+        Micro(-1), datetime(2010, 1, 1, 0, 0, 0, 1), datetime(2010, 1, 1)
+    )
+
+    assert_offset_equal(
+        2 * Micro(), datetime(2010, 1, 1), datetime(2010, 1, 1, 0, 0, 0, 2)
+    )
+    assert_offset_equal(
+        -1 * Micro(), datetime(2010, 1, 1, 0, 0, 0, 1), datetime(2010, 1, 1)
+    )
+
+    assert Micro(3) + Micro(2) == Micro(5)
+    assert Micro(3) - Micro(2) == Micro()
+
+
+def test_NanosecondGeneric():
+    timestamp = Timestamp(datetime(2010, 1, 1))
+    assert timestamp.nanosecond == 0
+
+    result = timestamp + Nano(10)
+    assert result.nanosecond == 10
+
+    reverse_result = Nano(10) + timestamp
+    assert reverse_result.nanosecond == 10
+
+
+def test_Nanosecond():
+    timestamp = Timestamp(datetime(2010, 1, 1))
+    assert_offset_equal(Nano(), timestamp, timestamp + np.timedelta64(1, "ns"))
+    assert_offset_equal(Nano(-1), timestamp + np.timedelta64(1, "ns"), timestamp)
+    assert_offset_equal(2 * Nano(), timestamp, timestamp + np.timedelta64(2, "ns"))
+    assert_offset_equal(-1 * Nano(), timestamp + np.timedelta64(1, "ns"), timestamp)
+
+    assert Nano(3) + Nano(2) == Nano(5)
+    assert Nano(3) - Nano(2) == Nano()
+
+    # GH9284
+    assert Nano(1) + Nano(10) == Nano(11)
+    assert Nano(5) + Micro(1) == Nano(1005)
+    assert Micro(5) + Nano(1) == Nano(5001)
+
+
+@pytest.mark.parametrize(
+    "kls, expected",
+    [
+        (Hour, Timedelta(hours=5)),
+        (Minute, Timedelta(hours=2, minutes=3)),
+        (Second, Timedelta(hours=2, seconds=3)),
+        (Milli, Timedelta(hours=2, milliseconds=3)),
+        (Micro, Timedelta(hours=2, microseconds=3)),
+        (Nano, Timedelta(hours=2, nanoseconds=3)),
+    ],
+)
+def test_tick_addition(kls, expected):
+    offset = kls(3)
+    td = Timedelta(hours=2)
+
+    for other in [td, td.to_pytimedelta(), td.to_timedelta64()]:
+        result = offset + other
+        assert isinstance(result, Timedelta)
+        assert result == expected
+
+        result = other + offset
+        assert isinstance(result, Timedelta)
+        assert result == expected
+
+
+def test_tick_delta_overflow():
+    # GH#55503 raise OutOfBoundsTimedelta, not OverflowError
+    tick = offsets.Day(10**9)
+    msg = "Cannot cast 1000000000 days 00:00:00 to unit='ns' without overflow"
+    depr_msg = "Day.delta is deprecated"
+    with pytest.raises(OutOfBoundsTimedelta, match=msg):
+        with tm.assert_produces_warning(FutureWarning, match=depr_msg):
+            tick.delta
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_tick_division(cls):
+    off = cls(10)
+
+    assert off / cls(5) == 2
+    assert off / 2 == cls(5)
+    assert off / 2.0 == cls(5)
+
+    assert off / off._as_pd_timedelta == 1
+    assert off / off._as_pd_timedelta.to_timedelta64() == 1
+
+    assert off / Nano(1) == off._as_pd_timedelta / Nano(1)._as_pd_timedelta
+
+    if cls is not Nano:
+        # A case where we end up with a smaller class
+        result = off / 1000
+        assert isinstance(result, offsets.Tick)
+        assert not isinstance(result, cls)
+        assert result._as_pd_timedelta == off._as_pd_timedelta / 1000
+
+    if cls._nanos_inc < Timedelta(seconds=1)._value:
+        # Case where we end up with a bigger class
+        result = off / 0.001
+        assert isinstance(result, offsets.Tick)
+        assert not isinstance(result, cls)
+        assert result._as_pd_timedelta == off._as_pd_timedelta / 0.001
+
+
+def test_tick_mul_float():
+    off = Micro(2)
+
+    # Case where we retain type
+    result = off * 1.5
+    expected = Micro(3)
+    assert result == expected
+    assert isinstance(result, Micro)
+
+    # Case where we bump up to the next type
+    result = off * 1.25
+    expected = Nano(2500)
+    assert result == expected
+    assert isinstance(result, Nano)
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_tick_rdiv(cls):
+    off = cls(10)
+    delta = off._as_pd_timedelta
+    td64 = delta.to_timedelta64()
+    instance__type = ".".join([cls.__module__, cls.__name__])
+    msg = (
+        "unsupported operand type\\(s\\) for \\/: 'int'|'float' and "
+        f"'{instance__type}'"
+    )
+
+    with pytest.raises(TypeError, match=msg):
+        2 / off
+    with pytest.raises(TypeError, match=msg):
+        2.0 / off
+
+    assert (td64 * 2.5) / off == 2.5
+
+    if cls is not Nano:
+        # skip pytimedelta for Nano since it gets dropped
+        assert (delta.to_pytimedelta() * 2) / off == 2
+
+    result = np.array([2 * td64, td64]) / off
+    expected = np.array([2.0, 1.0])
+    tm.assert_numpy_array_equal(result, expected)
+
+
+@pytest.mark.parametrize("cls1", tick_classes)
+@pytest.mark.parametrize("cls2", tick_classes)
+def test_tick_zero(cls1, cls2):
+    assert cls1(0) == cls2(0)
+    assert cls1(0) + cls2(0) == cls1(0)
+
+    if cls1 is not Nano:
+        assert cls1(2) + cls2(0) == cls1(2)
+
+    if cls1 is Nano:
+        assert cls1(2) + Nano(0) == cls1(2)
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_tick_equalities(cls):
+    assert cls() == cls(1)
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_tick_offset(cls):
+    msg = f"{cls.__name__}.is_anchored is deprecated "
+
+    with tm.assert_produces_warning(FutureWarning, match=msg):
+        assert not cls().is_anchored()
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_compare_ticks(cls):
+    three = cls(3)
+    four = cls(4)
+
+    assert three < cls(4)
+    assert cls(3) < four
+    assert four > cls(3)
+    assert cls(4) > three
+    assert cls(3) == cls(3)
+    assert cls(3) != cls(4)
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_compare_ticks_to_strs(cls):
+    # GH#23524
+    off = cls(19)
+
+    # These tests should work with any strings, but we particularly are
+    #  interested in "infer" as that comparison is convenient to make in
+    #  Datetime/Timedelta Array/Index constructors
+    assert not off == "infer"
+    assert not "foo" == off
+
+    instance_type = ".".join([cls.__module__, cls.__name__])
+    msg = (
+        "'<'|'<='|'>'|'>=' not supported between instances of "
+        f"'str' and '{instance_type}'|'{instance_type}' and 'str'"
+    )
+
+    for left, right in [("infer", off), (off, "infer")]:
+        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
+
+
+@pytest.mark.parametrize("cls", tick_classes)
+def test_compare_ticks_to_timedeltalike(cls):
+    off = cls(19)
+
+    td = off._as_pd_timedelta
+
+    others = [td, td.to_timedelta64()]
+    if cls is not Nano:
+        others.append(td.to_pytimedelta())
+
+    for other in others:
+        assert off == other
+        assert not off != other
+        assert not off < other
+        assert not off > other
+        assert off <= other
+        assert off >= other

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_week.py

@@ -0,0 +1,351 @@
+"""
+Tests for the following offsets:
+- Week
+- WeekOfMonth
+- LastWeekOfMonth
+"""
+from __future__ import annotations
+
+from datetime import (
+    datetime,
+    timedelta,
+)
+
+import pytest
+
+from pandas._libs.tslibs import Timestamp
+from pandas._libs.tslibs.offsets import (
+    Day,
+    LastWeekOfMonth,
+    Week,
+    WeekOfMonth,
+)
+
+import pandas._testing as tm
+from pandas.tests.tseries.offsets.common import (
+    WeekDay,
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+
+class TestWeek:
+    def test_repr(self):
+        assert repr(Week(weekday=0)) == "<Week: weekday=0>"
+        assert repr(Week(n=-1, weekday=0)) == "<-1 * Week: weekday=0>"
+        assert repr(Week(n=-2, weekday=0)) == "<-2 * Weeks: weekday=0>"
+
+    def test_corner(self):
+        with pytest.raises(ValueError, match="Day must be"):
+            Week(weekday=7)
+
+        with pytest.raises(ValueError, match="Day must be"):
+            Week(weekday=-1)
+
+    def test_is_anchored(self):
+        msg = "Week.is_anchored is deprecated "
+
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            assert Week(weekday=0).is_anchored()
+            assert not Week().is_anchored()
+            assert not Week(2, weekday=2).is_anchored()
+            assert not Week(2).is_anchored()
+
+    offset_cases = []
+    # not business week
+    offset_cases.append(
+        (
+            Week(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 8),
+                datetime(2008, 1, 4): datetime(2008, 1, 11),
+                datetime(2008, 1, 5): datetime(2008, 1, 12),
+                datetime(2008, 1, 6): datetime(2008, 1, 13),
+                datetime(2008, 1, 7): datetime(2008, 1, 14),
+            },
+        )
+    )
+
+    # Mon
+    offset_cases.append(
+        (
+            Week(weekday=0),
+            {
+                datetime(2007, 12, 31): datetime(2008, 1, 7),
+                datetime(2008, 1, 4): datetime(2008, 1, 7),
+                datetime(2008, 1, 5): datetime(2008, 1, 7),
+                datetime(2008, 1, 6): datetime(2008, 1, 7),
+                datetime(2008, 1, 7): datetime(2008, 1, 14),
+            },
+        )
+    )
+
+    # n=0 -> roll forward. Mon
+    offset_cases.append(
+        (
+            Week(0, weekday=0),
+            {
+                datetime(2007, 12, 31): datetime(2007, 12, 31),
+                datetime(2008, 1, 4): datetime(2008, 1, 7),
+                datetime(2008, 1, 5): datetime(2008, 1, 7),
+                datetime(2008, 1, 6): datetime(2008, 1, 7),
+                datetime(2008, 1, 7): datetime(2008, 1, 7),
+            },
+        )
+    )
+
+    # n=0 -> roll forward. Mon
+    offset_cases.append(
+        (
+            Week(-2, weekday=1),
+            {
+                datetime(2010, 4, 6): datetime(2010, 3, 23),
+                datetime(2010, 4, 8): datetime(2010, 3, 30),
+                datetime(2010, 4, 5): datetime(2010, 3, 23),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    @pytest.mark.parametrize("weekday", range(7))
+    def test_is_on_offset(self, weekday):
+        offset = Week(weekday=weekday)
+
+        for day in range(1, 8):
+            date = datetime(2008, 1, day)
+            expected = day % 7 == weekday
+        assert_is_on_offset(offset, date, expected)
+
+    @pytest.mark.parametrize(
+        "n,date",
+        [
+            (2, "1862-01-13 09:03:34.873477378+0210"),
+            (-2, "1856-10-24 16:18:36.556360110-0717"),
+        ],
+    )
+    def test_is_on_offset_weekday_none(self, n, date):
+        # GH 18510 Week with weekday = None, normalize = False
+        # should always be is_on_offset
+        offset = Week(n=n, weekday=None)
+        ts = Timestamp(date, tz="Africa/Lusaka")
+        fast = offset.is_on_offset(ts)
+        slow = (ts + offset) - offset == ts
+        assert fast == slow
+
+    def test_week_add_invalid(self):
+        # Week with weekday should raise TypeError and _not_ AttributeError
+        #  when adding invalid offset
+        offset = Week(weekday=1)
+        other = Day()
+        with pytest.raises(TypeError, match="Cannot add"):
+            offset + other
+
+
+class TestWeekOfMonth:
+    def test_constructor(self):
+        with pytest.raises(ValueError, match="^Week"):
+            WeekOfMonth(n=1, week=4, weekday=0)
+
+        with pytest.raises(ValueError, match="^Week"):
+            WeekOfMonth(n=1, week=-1, weekday=0)
+
+        with pytest.raises(ValueError, match="^Day"):
+            WeekOfMonth(n=1, week=0, weekday=-1)
+
+        with pytest.raises(ValueError, match="^Day"):
+            WeekOfMonth(n=1, week=0, weekday=-7)
+
+    def test_repr(self):
+        assert (
+            repr(WeekOfMonth(weekday=1, week=2)) == "<WeekOfMonth: week=2, weekday=1>"
+        )
+
+    def test_offset(self):
+        date1 = datetime(2011, 1, 4)  # 1st Tuesday of Month
+        date2 = datetime(2011, 1, 11)  # 2nd Tuesday of Month
+        date3 = datetime(2011, 1, 18)  # 3rd Tuesday of Month
+        date4 = datetime(2011, 1, 25)  # 4th Tuesday of Month
+
+        # see for loop for structure
+        test_cases = [
+            (-2, 2, 1, date1, datetime(2010, 11, 16)),
+            (-2, 2, 1, date2, datetime(2010, 11, 16)),
+            (-2, 2, 1, date3, datetime(2010, 11, 16)),
+            (-2, 2, 1, date4, datetime(2010, 12, 21)),
+            (-1, 2, 1, date1, datetime(2010, 12, 21)),
+            (-1, 2, 1, date2, datetime(2010, 12, 21)),
+            (-1, 2, 1, date3, datetime(2010, 12, 21)),
+            (-1, 2, 1, date4, datetime(2011, 1, 18)),
+            (0, 0, 1, date1, datetime(2011, 1, 4)),
+            (0, 0, 1, date2, datetime(2011, 2, 1)),
+            (0, 0, 1, date3, datetime(2011, 2, 1)),
+            (0, 0, 1, date4, datetime(2011, 2, 1)),
+            (0, 1, 1, date1, datetime(2011, 1, 11)),
+            (0, 1, 1, date2, datetime(2011, 1, 11)),
+            (0, 1, 1, date3, datetime(2011, 2, 8)),
+            (0, 1, 1, date4, datetime(2011, 2, 8)),
+            (0, 0, 1, date1, datetime(2011, 1, 4)),
+            (0, 1, 1, date2, datetime(2011, 1, 11)),
+            (0, 2, 1, date3, datetime(2011, 1, 18)),
+            (0, 3, 1, date4, datetime(2011, 1, 25)),
+            (1, 0, 0, date1, datetime(2011, 2, 7)),
+            (1, 0, 0, date2, datetime(2011, 2, 7)),
+            (1, 0, 0, date3, datetime(2011, 2, 7)),
+            (1, 0, 0, date4, datetime(2011, 2, 7)),
+            (1, 0, 1, date1, datetime(2011, 2, 1)),
+            (1, 0, 1, date2, datetime(2011, 2, 1)),
+            (1, 0, 1, date3, datetime(2011, 2, 1)),
+            (1, 0, 1, date4, datetime(2011, 2, 1)),
+            (1, 0, 2, date1, datetime(2011, 1, 5)),
+            (1, 0, 2, date2, datetime(2011, 2, 2)),
+            (1, 0, 2, date3, datetime(2011, 2, 2)),
+            (1, 0, 2, date4, datetime(2011, 2, 2)),
+            (1, 2, 1, date1, datetime(2011, 1, 18)),
+            (1, 2, 1, date2, datetime(2011, 1, 18)),
+            (1, 2, 1, date3, datetime(2011, 2, 15)),
+            (1, 2, 1, date4, datetime(2011, 2, 15)),
+            (2, 2, 1, date1, datetime(2011, 2, 15)),
+            (2, 2, 1, date2, datetime(2011, 2, 15)),
+            (2, 2, 1, date3, datetime(2011, 3, 15)),
+            (2, 2, 1, date4, datetime(2011, 3, 15)),
+        ]
+
+        for n, week, weekday, dt, expected in test_cases:
+            offset = WeekOfMonth(n, week=week, weekday=weekday)
+            assert_offset_equal(offset, dt, expected)
+
+        # try subtracting
+        result = datetime(2011, 2, 1) - WeekOfMonth(week=1, weekday=2)
+        assert result == datetime(2011, 1, 12)
+
+        result = datetime(2011, 2, 3) - WeekOfMonth(week=0, weekday=2)
+        assert result == datetime(2011, 2, 2)
+
+    on_offset_cases = [
+        (0, 0, datetime(2011, 2, 7), True),
+        (0, 0, datetime(2011, 2, 6), False),
+        (0, 0, datetime(2011, 2, 14), False),
+        (1, 0, datetime(2011, 2, 14), True),
+        (0, 1, datetime(2011, 2, 1), True),
+        (0, 1, datetime(2011, 2, 8), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        week, weekday, dt, expected = case
+        offset = WeekOfMonth(week=week, weekday=weekday)
+        assert offset.is_on_offset(dt) == expected
+
+    @pytest.mark.parametrize(
+        "n,week,date,tz",
+        [
+            (2, 2, "1916-05-15 01:14:49.583410462+0422", "Asia/Qyzylorda"),
+            (-3, 1, "1980-12-08 03:38:52.878321185+0500", "Asia/Oral"),
+        ],
+    )
+    def test_is_on_offset_nanoseconds(self, n, week, date, tz):
+        # GH 18864
+        # Make sure that nanoseconds don't trip up is_on_offset (and with it apply)
+        offset = WeekOfMonth(n=n, week=week, weekday=0)
+        ts = Timestamp(date, tz=tz)
+        fast = offset.is_on_offset(ts)
+        slow = (ts + offset) - offset == ts
+        assert fast == slow
+
+
+class TestLastWeekOfMonth:
+    def test_constructor(self):
+        with pytest.raises(ValueError, match="^N cannot be 0"):
+            LastWeekOfMonth(n=0, weekday=1)
+
+        with pytest.raises(ValueError, match="^Day"):
+            LastWeekOfMonth(n=1, weekday=-1)
+
+        with pytest.raises(ValueError, match="^Day"):
+            LastWeekOfMonth(n=1, weekday=7)
+
+    def test_offset(self):
+        # Saturday
+        last_sat = datetime(2013, 8, 31)
+        next_sat = datetime(2013, 9, 28)
+        offset_sat = LastWeekOfMonth(n=1, weekday=5)
+
+        one_day_before = last_sat + timedelta(days=-1)
+        assert one_day_before + offset_sat == last_sat
+
+        one_day_after = last_sat + timedelta(days=+1)
+        assert one_day_after + offset_sat == next_sat
+
+        # Test On that day
+        assert last_sat + offset_sat == next_sat
+
+        # Thursday
+
+        offset_thur = LastWeekOfMonth(n=1, weekday=3)
+        last_thurs = datetime(2013, 1, 31)
+        next_thurs = datetime(2013, 2, 28)
+
+        one_day_before = last_thurs + timedelta(days=-1)
+        assert one_day_before + offset_thur == last_thurs
+
+        one_day_after = last_thurs + timedelta(days=+1)
+        assert one_day_after + offset_thur == next_thurs
+
+        # Test on that day
+        assert last_thurs + offset_thur == next_thurs
+
+        three_before = last_thurs + timedelta(days=-3)
+        assert three_before + offset_thur == last_thurs
+
+        two_after = last_thurs + timedelta(days=+2)
+        assert two_after + offset_thur == next_thurs
+
+        offset_sunday = LastWeekOfMonth(n=1, weekday=WeekDay.SUN)
+        assert datetime(2013, 7, 31) + offset_sunday == datetime(2013, 8, 25)
+
+    on_offset_cases = [
+        (WeekDay.SUN, datetime(2013, 1, 27), True),
+        (WeekDay.SAT, datetime(2013, 3, 30), True),
+        (WeekDay.MON, datetime(2013, 2, 18), False),  # Not the last Mon
+        (WeekDay.SUN, datetime(2013, 2, 25), False),  # Not a SUN
+        (WeekDay.MON, datetime(2013, 2, 25), True),
+        (WeekDay.SAT, datetime(2013, 11, 30), True),
+        (WeekDay.SAT, datetime(2006, 8, 26), True),
+        (WeekDay.SAT, datetime(2007, 8, 25), True),
+        (WeekDay.SAT, datetime(2008, 8, 30), True),
+        (WeekDay.SAT, datetime(2009, 8, 29), True),
+        (WeekDay.SAT, datetime(2010, 8, 28), True),
+        (WeekDay.SAT, datetime(2011, 8, 27), True),
+        (WeekDay.SAT, datetime(2019, 8, 31), True),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        weekday, dt, expected = case
+        offset = LastWeekOfMonth(weekday=weekday)
+        assert offset.is_on_offset(dt) == expected
+
+    @pytest.mark.parametrize(
+        "n,weekday,date,tz",
+        [
+            (4, 6, "1917-05-27 20:55:27.084284178+0200", "Europe/Warsaw"),
+            (-4, 5, "2005-08-27 05:01:42.799392561-0500", "America/Rainy_River"),
+        ],
+    )
+    def test_last_week_of_month_on_offset(self, n, weekday, date, tz):
+        # GH 19036, GH 18977 _adjust_dst was incorrect for LastWeekOfMonth
+        offset = LastWeekOfMonth(n=n, weekday=weekday)
+        ts = Timestamp(date, tz=tz)
+        slow = (ts + offset) - offset == ts
+        fast = offset.is_on_offset(ts)
+        assert fast == slow
+
+    def test_repr(self):
+        assert (
+            repr(LastWeekOfMonth(n=2, weekday=1)) == "<2 * LastWeekOfMonths: weekday=1>"
+        )

lib/python3.13/site-packages/pandas/tests/tseries/offsets/test_year.py

@@ -0,0 +1,339 @@
+"""
+Tests for the following offsets:
+- YearBegin
+- YearEnd
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+import numpy as np
+import pytest
+
+from pandas import Timestamp
+from pandas.tests.tseries.offsets.common import (
+    assert_is_on_offset,
+    assert_offset_equal,
+)
+
+from pandas.tseries.offsets import (
+    YearBegin,
+    YearEnd,
+)
+
+
+class TestYearBegin:
+    def test_misspecified(self):
+        with pytest.raises(ValueError, match="Month must go from 1 to 12"):
+            YearBegin(month=13)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            YearBegin(),
+            {
+                datetime(2008, 1, 1): datetime(2009, 1, 1),
+                datetime(2008, 6, 30): datetime(2009, 1, 1),
+                datetime(2008, 12, 31): datetime(2009, 1, 1),
+                datetime(2005, 12, 30): datetime(2006, 1, 1),
+                datetime(2005, 12, 31): datetime(2006, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 1, 1),
+                datetime(2008, 6, 30): datetime(2009, 1, 1),
+                datetime(2008, 12, 31): datetime(2009, 1, 1),
+                datetime(2005, 12, 30): datetime(2006, 1, 1),
+                datetime(2005, 12, 31): datetime(2006, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(3),
+            {
+                datetime(2008, 1, 1): datetime(2011, 1, 1),
+                datetime(2008, 6, 30): datetime(2011, 1, 1),
+                datetime(2008, 12, 31): datetime(2011, 1, 1),
+                datetime(2005, 12, 30): datetime(2008, 1, 1),
+                datetime(2005, 12, 31): datetime(2008, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 1, 1),
+                datetime(2007, 1, 15): datetime(2007, 1, 1),
+                datetime(2008, 6, 30): datetime(2008, 1, 1),
+                datetime(2008, 12, 31): datetime(2008, 1, 1),
+                datetime(2006, 12, 29): datetime(2006, 1, 1),
+                datetime(2006, 12, 30): datetime(2006, 1, 1),
+                datetime(2007, 1, 1): datetime(2006, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(-2),
+            {
+                datetime(2007, 1, 1): datetime(2005, 1, 1),
+                datetime(2008, 6, 30): datetime(2007, 1, 1),
+                datetime(2008, 12, 31): datetime(2007, 1, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(month=4),
+            {
+                datetime(2007, 4, 1): datetime(2008, 4, 1),
+                datetime(2007, 4, 15): datetime(2008, 4, 1),
+                datetime(2007, 3, 1): datetime(2007, 4, 1),
+                datetime(2007, 12, 15): datetime(2008, 4, 1),
+                datetime(2012, 1, 31): datetime(2012, 4, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(0, month=4),
+            {
+                datetime(2007, 4, 1): datetime(2007, 4, 1),
+                datetime(2007, 3, 1): datetime(2007, 4, 1),
+                datetime(2007, 12, 15): datetime(2008, 4, 1),
+                datetime(2012, 1, 31): datetime(2012, 4, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(4, month=4),
+            {
+                datetime(2007, 4, 1): datetime(2011, 4, 1),
+                datetime(2007, 4, 15): datetime(2011, 4, 1),
+                datetime(2007, 3, 1): datetime(2010, 4, 1),
+                datetime(2007, 12, 15): datetime(2011, 4, 1),
+                datetime(2012, 1, 31): datetime(2015, 4, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(-1, month=4),
+            {
+                datetime(2007, 4, 1): datetime(2006, 4, 1),
+                datetime(2007, 3, 1): datetime(2006, 4, 1),
+                datetime(2007, 12, 15): datetime(2007, 4, 1),
+                datetime(2012, 1, 31): datetime(2011, 4, 1),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearBegin(-3, month=4),
+            {
+                datetime(2007, 4, 1): datetime(2004, 4, 1),
+                datetime(2007, 3, 1): datetime(2004, 4, 1),
+                datetime(2007, 12, 15): datetime(2005, 4, 1),
+                datetime(2012, 1, 31): datetime(2009, 4, 1),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (YearBegin(), datetime(2007, 1, 3), False),
+        (YearBegin(), datetime(2008, 1, 1), True),
+        (YearBegin(), datetime(2006, 12, 31), False),
+        (YearBegin(), datetime(2006, 1, 2), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+
+class TestYearEnd:
+    def test_misspecified(self):
+        with pytest.raises(ValueError, match="Month must go from 1 to 12"):
+            YearEnd(month=13)
+
+    offset_cases = []
+    offset_cases.append(
+        (
+            YearEnd(),
+            {
+                datetime(2008, 1, 1): datetime(2008, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 12, 31),
+                datetime(2008, 12, 31): datetime(2009, 12, 31),
+                datetime(2005, 12, 30): datetime(2005, 12, 31),
+                datetime(2005, 12, 31): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearEnd(0),
+            {
+                datetime(2008, 1, 1): datetime(2008, 12, 31),
+                datetime(2008, 6, 30): datetime(2008, 12, 31),
+                datetime(2008, 12, 31): datetime(2008, 12, 31),
+                datetime(2005, 12, 30): datetime(2005, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearEnd(-1),
+            {
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+                datetime(2008, 6, 30): datetime(2007, 12, 31),
+                datetime(2008, 12, 31): datetime(2007, 12, 31),
+                datetime(2006, 12, 29): datetime(2005, 12, 31),
+                datetime(2006, 12, 30): datetime(2005, 12, 31),
+                datetime(2007, 1, 1): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearEnd(-2),
+            {
+                datetime(2007, 1, 1): datetime(2005, 12, 31),
+                datetime(2008, 6, 30): datetime(2006, 12, 31),
+                datetime(2008, 12, 31): datetime(2006, 12, 31),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (YearEnd(), datetime(2007, 12, 31), True),
+        (YearEnd(), datetime(2008, 1, 1), False),
+        (YearEnd(), datetime(2006, 12, 31), True),
+        (YearEnd(), datetime(2006, 12, 29), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+
+class TestYearEndDiffMonth:
+    offset_cases = []
+    offset_cases.append(
+        (
+            YearEnd(month=3),
+            {
+                datetime(2008, 1, 1): datetime(2008, 3, 31),
+                datetime(2008, 2, 15): datetime(2008, 3, 31),
+                datetime(2008, 3, 31): datetime(2009, 3, 31),
+                datetime(2008, 3, 30): datetime(2008, 3, 31),
+                datetime(2005, 3, 31): datetime(2006, 3, 31),
+                datetime(2006, 7, 30): datetime(2007, 3, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearEnd(0, month=3),
+            {
+                datetime(2008, 1, 1): datetime(2008, 3, 31),
+                datetime(2008, 2, 28): datetime(2008, 3, 31),
+                datetime(2008, 3, 31): datetime(2008, 3, 31),
+                datetime(2005, 3, 30): datetime(2005, 3, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearEnd(-1, month=3),
+            {
+                datetime(2007, 1, 1): datetime(2006, 3, 31),
+                datetime(2008, 2, 28): datetime(2007, 3, 31),
+                datetime(2008, 3, 31): datetime(2007, 3, 31),
+                datetime(2006, 3, 29): datetime(2005, 3, 31),
+                datetime(2006, 3, 30): datetime(2005, 3, 31),
+                datetime(2007, 3, 1): datetime(2006, 3, 31),
+            },
+        )
+    )
+
+    offset_cases.append(
+        (
+            YearEnd(-2, month=3),
+            {
+                datetime(2007, 1, 1): datetime(2005, 3, 31),
+                datetime(2008, 6, 30): datetime(2007, 3, 31),
+                datetime(2008, 3, 31): datetime(2006, 3, 31),
+            },
+        )
+    )
+
+    @pytest.mark.parametrize("case", offset_cases)
+    def test_offset(self, case):
+        offset, cases = case
+        for base, expected in cases.items():
+            assert_offset_equal(offset, base, expected)
+
+    on_offset_cases = [
+        (YearEnd(month=3), datetime(2007, 3, 31), True),
+        (YearEnd(month=3), datetime(2008, 1, 1), False),
+        (YearEnd(month=3), datetime(2006, 3, 31), True),
+        (YearEnd(month=3), datetime(2006, 3, 29), False),
+    ]
+
+    @pytest.mark.parametrize("case", on_offset_cases)
+    def test_is_on_offset(self, case):
+        offset, dt, expected = case
+        assert_is_on_offset(offset, dt, expected)
+
+
+def test_add_out_of_pydatetime_range():
+    # GH#50348 don't raise in Timestamp.replace
+    ts = Timestamp(np.datetime64("-20000-12-31"))
+    off = YearEnd()
+
+    result = ts + off
+    # TODO(cython3): "arg: datetime" annotation will impose
+    # datetime limitations on Timestamp. The fused type below works in cy3
+    # ctypedef fused datetimelike:
+    #     _Timestamp
+    #     datetime
+    # expected = Timestamp(np.datetime64("-19999-12-31"))
+    # assert result == expected
+    assert result.year in (-19999, 1973)
+    assert result.month == 12
+    assert result.day == 31