Remove typing statements not supported by 3.8

xesmf/data.py

@@ -2,17 +2,17 @@
 Standard test data for regridding benchmark.
 """
 
-from typing import Any
+from typing import Union
 
 import numpy as np
 import numpy.typing as npt
 import xarray
 
 
 def wave_smooth(  # type: ignore
-    lon: npt.NDArray[np.floating[Any]] | xarray.DataArray,
-    lat: npt.NDArray[np.floating[Any]] | xarray.DataArray,
-) -> npt.NDArray[np.floating[Any]] | xarray.DataArray:
+    lon: Union[npt.NDArray, xarray.DataArray],
+    lat: Union[npt.NDArray, xarray.DataArray],
+) -> Union[npt.NDArray, xarray.DataArray]:
     """
     Spherical harmonic with low frequency.
 

xesmf/frontend.py

@@ -3,7 +3,7 @@
 """
 
 import warnings
-from typing import Any, Dict, Hashable, List, Literal, Optional, Sequence, Tuple
+from typing import Any, Dict, Hashable, List, Literal, Optional, Sequence, Tuple, Union
 
 import cf_xarray as cfxr
 import numpy as np
@@ -270,8 +270,8 @@ def polys_to_ESMFmesh(polys) -> tuple[Mesh, tuple[Literal[1], int]]:
 class BaseRegridder(object):
     def __init__(
         self,
-        grid_in: Grid | LocStream | Mesh,
-        grid_out: Grid | LocStream | Mesh,
+        grid_in: Union[Grid, LocStream, Mesh],
+        grid_out: Union[Grid, LocStream, Mesh],
         method: str,
         filename: Optional[str] = None,
         reuse_weights: bool = False,
@@ -492,7 +492,7 @@ def __call__(
         keep_attrs: bool = False,
         skipna: bool = False,
         na_thres: float = 1.0,
-        output_chunks: Optional[Dict[str, int] | Tuple[int, ...]] = None,
+        output_chunks: Optional[Union[Dict[str, int], Tuple[int, ...]]] = None,
     ):
         """
         Apply regridding to input data.
@@ -629,7 +629,7 @@ def regrid_array(
         weights: sps.coo_matrix,
         skipna: bool = False,
         na_thres: float = 1.0,
-        output_chunks: Optional[Tuple[int, ...] | Dict[str, int]] = None,
+        output_chunks: Optional[Union[Tuple[int, ...], Dict[str, int]]] = None,
     ):
         """See __call__()."""
         if self.sequence_in:
@@ -693,7 +693,7 @@ def regrid_dataarray(
         keep_attrs: bool = False,
         skipna: bool = False,
         na_thres: float = 1.0,
-        output_chunks: Optional[Dict[str, int] | Tuple[int, ...]] = None,
+        output_chunks: Optional[Union[Dict[str, int], Tuple[int, ...]]] = None,
     ) -> DataArray | Dataset:
         """See __call__()."""
 
@@ -718,7 +718,7 @@ def regrid_dataset(
         keep_attrs: bool = False,
         skipna: bool = False,
         na_thres: float = 1.0,
-        output_chunks: Optional[Dict[str, int] | Tuple[int, ...]] = None,
+        output_chunks: Optional[Union[Dict[str, int], Tuple[int, ...]]] = None,
     ) -> DataArray | Dataset:
         """See __call__()."""
 

xesmf/smm.py

@@ -3,7 +3,7 @@
 """
 import warnings
 from pathlib import Path
-from typing import Any, Tuple
+from typing import Any, Dict, Tuple, Union
 
 import numba as nb  # type: ignore[import]
 import numpy as np
@@ -13,7 +13,7 @@
 
 
 def read_weights(
-    weights: str | Path | xr.Dataset | xr.DataArray | sps.COO | dict[str, Any],
+    weights: Union[str, Path, xr.Dataset, xr.DataArray, sps.COO, Dict[str, Any]],
     n_in: int,
     n_out: int,
 ) -> xr.DataArray:
@@ -56,7 +56,7 @@ def read_weights(
 
 
 def _parse_coords_and_values(
-    indata: str | Path | xr.Dataset | dict[str, Any],
+    indata: Union[str, Path, xr.Dataset, Dict[str, Any]],
     n_in: int,
     n_out: int,
 ) -> xr.DataArray:

xesmf/util.py

@@ -1,5 +1,5 @@
 import warnings
-from typing import Any, Generator, List, Literal, Tuple
+from typing import Any, Generator, List, Literal, Tuple, Union
 
 import numpy as np
 import numpy.typing as npt
@@ -10,9 +10,7 @@
 LAT_CF_ATTRS = {'standard_name': 'latitude', 'units': 'degrees_north'}
 
 
-def _grid_1d(
-    start_b: float, end_b: float, step: float
-) -> tuple[npt.NDArray[np.floating[Any]], npt.NDArray[np.floating[Any]]]:
+def _grid_1d(start_b: float, end_b: float, step: float) -> Tuple[npt.NDArray, npt.NDArray]:
     """
     1D grid centers and bounds
 
@@ -191,7 +189,7 @@ def grid_global(
 
 def _flatten_poly_list(
     polys: List[Polygon],
-) -> Generator[tuple[int, Any] | tuple[int, Polygon], Any, None]:
+) -> Generator[Union[Tuple[int, Any], Tuple[int, Polygon]], Any, None]:
     """Iterator flattening MultiPolygons."""
     for i, poly in enumerate(polys):
         if isinstance(poly, MultiPolygon):
@@ -248,7 +246,7 @@ def simple_tripolar_grid(
     nlats: int,
     lat_cap: float = 60,
     lon_cut: float = -300,
-) -> tuple[npt.NDArray[np.floating[Any]], npt.NDArray[Any]]:
+) -> Tuple[npt.NDArray, npt.NDArray]:
     """Generate a simple tripolar grid, regular under `lat_cap`.
 
     Parameters