Address upstream failures revealed in #11043 (#11050)

* Explicitly set date_range unit in CFTimeIndex resample tests

* Explicitly set date_range unit in backend test

* Explicitly set date_range unit in conventions tests

* Explicitly set date_range unit in iris conversion tests

* Adjust formatting tests for new pandas str dtype

Author: spencerkclark

xarray/tests/test_backends.py

@@ -1486,7 +1486,7 @@ def test_encoding_unlimited_dims(self) -> None:
                 pass
 
     def test_encoding_kwarg_dates(self) -> None:
-        ds = Dataset({"t": pd.date_range("2000-01-01", periods=3)})
+        ds = Dataset({"t": pd.date_range("2000-01-01", periods=3, unit="ns")})
         units = "days since 1900-01-01"
         kwargs = dict(encoding={"t": {"units": units}})
         with self.roundtrip(ds, save_kwargs=kwargs) as actual:

xarray/tests/test_cftimeindex_resample.py

@@ -16,6 +16,7 @@
 )
 from xarray.coding.cftimeindex import CFTimeIndex
 from xarray.core.resample_cftime import CFTimeGrouper
+from xarray.core.types import PDDatetimeUnitOptions
 from xarray.tests import has_pandas_3
 
 cftime = pytest.importorskip("cftime")
@@ -141,7 +142,7 @@ def test_resample_with_tick_resample_freq(freqs, closed, label, offset) -> None:
     origin = "start"
 
     datetime_index = pd.date_range(
-        start=start, periods=5, freq=_new_to_legacy_freq(initial_freq)
+        start=start, periods=5, freq=_new_to_legacy_freq(initial_freq), unit="ns"
     )
     cftime_index = xr.date_range(
         start=start, periods=5, freq=initial_freq, use_cftime=True
@@ -178,7 +179,7 @@ def test_resample_with_non_tick_resample_freq(freqs, closed, label) -> None:
     origin = "start_day"
 
     datetime_index = pd.date_range(
-        start=start, periods=5, freq=_new_to_legacy_freq(initial_freq)
+        start=start, periods=5, freq=_new_to_legacy_freq(initial_freq), unit="ns"
     )
     cftime_index = xr.date_range(
         start=start, periods=5, freq=initial_freq, use_cftime=True
@@ -231,7 +232,9 @@ def test_calendars(calendar: str) -> None:
         calendar=calendar,
         use_cftime=True,
     )
-    pd_index = pd.date_range(start="2004-01-01T12:07:01", periods=7, freq="3D")
+    pd_index = pd.date_range(
+        start="2004-01-01T12:07:01", periods=7, freq="3D", unit="ns"
+    )
     da_cftime = da(xr_index).resample(time=freq, closed=closed, label=label).mean()
     da_datetime = da(pd_index).resample(time=freq, closed=closed, label=label).mean()
     # TODO (benbovy - flexible indexes): update when CFTimeIndex is a xarray Index subclass
@@ -245,6 +248,7 @@ class DateRangeKwargs(TypedDict):
     start: str
     periods: int
     freq: str
+    unit: PDDatetimeUnitOptions
 
 
 @pytest.mark.parametrize("closed", ["left", "right"])
@@ -256,7 +260,9 @@ class DateRangeKwargs(TypedDict):
 def test_origin(closed, origin) -> None:
     initial_freq, resample_freq = ("3h", "9h")
     start = "1969-12-31T12:07:01"
-    index_kwargs: DateRangeKwargs = dict(start=start, periods=12, freq=initial_freq)
+    index_kwargs: DateRangeKwargs = dict(
+        start=start, periods=12, freq=initial_freq, unit="ns"
+    )
     datetime_index = pd.date_range(**index_kwargs)
     cftime_index = xr.date_range(**index_kwargs, use_cftime=True)
     da_datetimeindex = da(datetime_index)

xarray/tests/test_conventions.py

@@ -280,7 +280,7 @@ def test_dataset(self) -> None:
         expected = Dataset(
             {"foo": ("t", [0, 0, 0], {"units": "bar"})},
             {
-                "t": pd.date_range("2000-01-01", periods=3),
+                "t": pd.date_range("2000-01-01", periods=3, unit="ns"),
                 "y": ("t", [5.0, 10.0, np.nan]),
             },
         )
@@ -422,7 +422,7 @@ def test_decode_cf_with_drop_variables(self) -> None:
         )
         expected = Dataset(
             {
-                "t": pd.date_range("2000-01-01", periods=3),
+                "t": pd.date_range("2000-01-01", periods=3, unit="ns"),
                 "foo": (
                     ("t", "x"),
                     [[0, 0, 0], [1, 1, 1], [2, 2, 2]],

xarray/tests/test_dataarray.py

@@ -7002,7 +7002,7 @@ def test_to_and_from_iris(self) -> None:
         # to iris
         coord_dict: dict[Hashable, Any] = {}
         coord_dict["distance"] = ("distance", [-2, 2], {"units": "meters"})
-        coord_dict["time"] = ("time", pd.date_range("2000-01-01", periods=3))
+        coord_dict["time"] = ("time", pd.date_range("2000-01-01", periods=3, unit="ns"))
         coord_dict["height"] = 10
         coord_dict["distance2"] = ("distance", [0, 1], {"foo": "bar"})
         coord_dict["time2"] = (("distance", "time"), [[0, 1, 2], [2, 3, 4]])
@@ -7073,7 +7073,7 @@ def test_to_and_from_iris_dask(self) -> None:
 
         coord_dict: dict[Hashable, Any] = {}
         coord_dict["distance"] = ("distance", [-2, 2], {"units": "meters"})
-        coord_dict["time"] = ("time", pd.date_range("2000-01-01", periods=3))
+        coord_dict["time"] = ("time", pd.date_range("2000-01-01", periods=3, unit="ns"))
         coord_dict["height"] = 10
         coord_dict["distance2"] = ("distance", [0, 1], {"foo": "bar"})
         coord_dict["time2"] = (("distance", "time"), [[0, 1, 2], [2, 3, 4]])

xarray/tests/test_formatting.py

@@ -10,7 +10,7 @@
 import xarray as xr
 from xarray.core import formatting
 from xarray.core.indexes import Index
-from xarray.tests import requires_cftime, requires_dask, requires_netCDF4
+from xarray.tests import has_pandas_3, requires_cftime, requires_dask, requires_netCDF4
 
 
 class CustomIndex(Index):
@@ -297,6 +297,7 @@ def test_diff_array_repr(self) -> None:
         )
 
         byteorder = "<" if sys.byteorder == "little" else ">"
+        str_dtype = "str" if has_pandas_3 else "object"
         expected = dedent(
             f"""\
         Left and right DataArray objects are not identical
@@ -317,8 +318,8 @@ def test_diff_array_repr(self) -> None:
             label    (x) int64 16B 1 2
         Indexes only on the left object:  ['y']
         Differing indexes:
-        L   x                    Index(['a', 'b'], dtype='object', name='x')
-        R   x                    Index(['a', 'c'], dtype='object', name='x')
+        L   x                    Index(['a', 'b'], dtype='{str_dtype}', name='x')
+        R   x                    Index(['a', 'c'], dtype='{str_dtype}', name='x')
         Differing attributes:
         L   units: m
         R   units: kg
@@ -501,6 +502,7 @@ def test_diff_dataset_repr(self) -> None:
         )
 
         byteorder = "<" if sys.byteorder == "little" else ">"
+        str_dtype = "str" if has_pandas_3 else "object"
         expected = dedent(
             f"""\
         Left and right Dataset objects are not identical
@@ -525,8 +527,8 @@ def test_diff_dataset_repr(self) -> None:
             var2     (x) int64 16B 3 4
         Indexes only on the left object:  ['y']
         Differing indexes:
-        L   x                    Index(['a', 'b'], dtype='object', name='x')
-        R   x                    Index(['a', 'c'], dtype='object', name='x')
+        L   x                    Index(['a', 'b'], dtype='{str_dtype}', name='x')
+        R   x                    Index(['a', 'c'], dtype='{str_dtype}', name='x')
         Differing attributes:
         L   title: mytitle
         R   title: newtitle