from datetime import datetime import numpy as np import pytest import pytz from pandas import ( NA, DatetimeIndex, Index, NaT, Timestamp, date_range, ) import pandas._testing as tm class TestInsert: @pytest.mark.parametrize("null", [None, np.nan, np.datetime64("NaT"), NaT, NA]) @pytest.mark.parametrize("tz", [None, "UTC", "US/Eastern"]) def test_insert_nat(self, tz, null): # GH#16537, GH#18295 (test missing) idx = DatetimeIndex(["2017-01-01"], tz=tz) expected = DatetimeIndex(["NaT", "2017-01-01"], tz=tz) if tz is not None and isinstance(null, np.datetime64): expected = Index([null, idx[0]], dtype=object) res = idx.insert(0, null) tm.assert_index_equal(res, expected) @pytest.mark.parametrize("tz", [None, "UTC", "US/Eastern"]) def test_insert_invalid_na(self, tz): idx = DatetimeIndex(["2017-01-01"], tz=tz) item = np.timedelta64("NaT") result = idx.insert(0, item) expected = Index([item] + list(idx), dtype=object) tm.assert_index_equal(result, expected) def test_insert_empty_preserves_freq(self, tz_naive_fixture): # GH#33573 tz = tz_naive_fixture dti = DatetimeIndex([], tz=tz, freq="D") item = Timestamp("2017-04-05").tz_localize(tz) result = dti.insert(0, item) assert result.freq == dti.freq # But not when we insert an item that doesn't conform to freq dti = DatetimeIndex([], tz=tz, freq="W-THU") result = dti.insert(0, item) assert result.freq is None def test_insert(self): idx = DatetimeIndex(["2000-01-04", "2000-01-01", "2000-01-02"], name="idx") result = idx.insert(2, datetime(2000, 1, 5)) exp = DatetimeIndex( ["2000-01-04", "2000-01-01", "2000-01-05", "2000-01-02"], name="idx" ) tm.assert_index_equal(result, exp) # insertion of non-datetime should coerce to object index result = idx.insert(1, "inserted") expected = Index( [ datetime(2000, 1, 4), "inserted", datetime(2000, 1, 1), datetime(2000, 1, 2), ], name="idx", ) assert not isinstance(result, DatetimeIndex) tm.assert_index_equal(result, expected) assert result.name == expected.name idx = date_range("1/1/2000", periods=3, freq="M", name="idx") # preserve freq expected_0 = DatetimeIndex( ["1999-12-31", "2000-01-31", "2000-02-29", "2000-03-31"], name="idx", freq="M", ) expected_3 = DatetimeIndex( ["2000-01-31", "2000-02-29", "2000-03-31", "2000-04-30"], name="idx", freq="M", ) # reset freq to None expected_1_nofreq = DatetimeIndex( ["2000-01-31", "2000-01-31", "2000-02-29", "2000-03-31"], name="idx", freq=None, ) expected_3_nofreq = DatetimeIndex( ["2000-01-31", "2000-02-29", "2000-03-31", "2000-01-02"], name="idx", freq=None, ) cases = [ (0, datetime(1999, 12, 31), expected_0), (-3, datetime(1999, 12, 31), expected_0), (3, datetime(2000, 4, 30), expected_3), (1, datetime(2000, 1, 31), expected_1_nofreq), (3, datetime(2000, 1, 2), expected_3_nofreq), ] for n, d, expected in cases: result = idx.insert(n, d) tm.assert_index_equal(result, expected) assert result.name == expected.name assert result.freq == expected.freq # reset freq to None result = idx.insert(3, datetime(2000, 1, 2)) expected = DatetimeIndex( ["2000-01-31", "2000-02-29", "2000-03-31", "2000-01-02"], name="idx", freq=None, ) tm.assert_index_equal(result, expected) assert result.name == expected.name assert result.freq is None for tz in ["US/Pacific", "Asia/Singapore"]: idx = date_range("1/1/2000 09:00", periods=6, freq="H", tz=tz, name="idx") # preserve freq expected = date_range( "1/1/2000 09:00", periods=7, freq="H", tz=tz, name="idx" ) for d in [ Timestamp("2000-01-01 15:00", tz=tz), pytz.timezone(tz).localize(datetime(2000, 1, 1, 15)), ]: result = idx.insert(6, d) tm.assert_index_equal(result, expected) assert result.name == expected.name assert result.freq == expected.freq assert result.tz == expected.tz expected = DatetimeIndex( [ "2000-01-01 09:00", "2000-01-01 10:00", "2000-01-01 11:00", "2000-01-01 12:00", "2000-01-01 13:00", "2000-01-01 14:00", "2000-01-01 10:00", ], name="idx", tz=tz, freq=None, ) # reset freq to None for d in [ Timestamp("2000-01-01 10:00", tz=tz), pytz.timezone(tz).localize(datetime(2000, 1, 1, 10)), ]: result = idx.insert(6, d) tm.assert_index_equal(result, expected) assert result.name == expected.name assert result.tz == expected.tz assert result.freq is None # TODO: also changes DataFrame.__setitem__ with expansion def test_insert_mismatched_tzawareness(self): # see GH#7299 idx = date_range("1/1/2000", periods=3, freq="D", tz="Asia/Tokyo", name="idx") # mismatched tz-awareness item = Timestamp("2000-01-04") result = idx.insert(3, item) expected = Index( list(idx[:3]) + [item] + list(idx[3:]), dtype=object, name="idx" ) tm.assert_index_equal(result, expected) # mismatched tz-awareness item = datetime(2000, 1, 4) result = idx.insert(3, item) expected = Index( list(idx[:3]) + [item] + list(idx[3:]), dtype=object, name="idx" ) tm.assert_index_equal(result, expected) # TODO: also changes DataFrame.__setitem__ with expansion def test_insert_mismatched_tz(self): # see GH#7299 # pre-2.0 with mismatched tzs we would cast to object idx = date_range("1/1/2000", periods=3, freq="D", tz="Asia/Tokyo", name="idx") # mismatched tz -> cast to object (could reasonably cast to same tz or UTC) item = Timestamp("2000-01-04", tz="US/Eastern") result = idx.insert(3, item) expected = Index( list(idx[:3]) + [item.tz_convert(idx.tz)] + list(idx[3:]), name="idx", ) assert expected.dtype == idx.dtype tm.assert_index_equal(result, expected) item = datetime(2000, 1, 4, tzinfo=pytz.timezone("US/Eastern")) result = idx.insert(3, item) expected = Index( list(idx[:3]) + [item.astimezone(idx.tzinfo)] + list(idx[3:]), name="idx", ) assert expected.dtype == idx.dtype tm.assert_index_equal(result, expected) @pytest.mark.parametrize( "item", [0, np.int64(0), np.float64(0), np.array(0), np.timedelta64(456)] ) def test_insert_mismatched_types_raises(self, tz_aware_fixture, item): # GH#33703 dont cast these to dt64 tz = tz_aware_fixture dti = date_range("2019-11-04", periods=9, freq="-1D", name=9, tz=tz) result = dti.insert(1, item) if isinstance(item, np.ndarray): assert item.item() == 0 expected = Index([dti[0], 0] + list(dti[1:]), dtype=object, name=9) else: expected = Index([dti[0], item] + list(dti[1:]), dtype=object, name=9) tm.assert_index_equal(result, expected) def test_insert_castable_str(self, tz_aware_fixture): # GH#33703 tz = tz_aware_fixture dti = date_range("2019-11-04", periods=3, freq="-1D", name=9, tz=tz) value = "2019-11-05" result = dti.insert(0, value) ts = Timestamp(value).tz_localize(tz) expected = DatetimeIndex([ts] + list(dti), dtype=dti.dtype, name=9) tm.assert_index_equal(result, expected) def test_insert_non_castable_str(self, tz_aware_fixture): # GH#33703 tz = tz_aware_fixture dti = date_range("2019-11-04", periods=3, freq="-1D", name=9, tz=tz) value = "foo" result = dti.insert(0, value) expected = Index(["foo"] + list(dti), dtype=object, name=9) tm.assert_index_equal(result, expected)