Remove legacy netcdf test and supporting sanitization code

Per: #474 (comment)

Author: alexander0042

src/herbie/core.py

@@ -22,7 +22,6 @@
 from urllib.parse import urlparse
 
 import cfgrib
-import numpy as np
 import pandas as pd
 import requests
 import xarray as xr
@@ -52,58 +51,6 @@
         "Curl is not in system Path. Herbie won't be able to download GRIB files."
     )
 
-
-_INT32_MIN = np.iinfo(np.int32).min
-_INT32_MAX = np.iinfo(np.int32).max
-
-
-def _sanitize_attr_value(value):
-    """Convert attribute values so they are compatible with NetCDF3 writers."""
-
-    if isinstance(value, np.integer):
-        value = int(value)
-        if value < _INT32_MIN or value > _INT32_MAX:
-            return float(value)
-        return value
-    if isinstance(value, np.floating):
-        return float(value)
-    if isinstance(value, np.ndarray):
-        return [_sanitize_attr_value(v) for v in value.tolist()]
-    if isinstance(value, list):
-        return [_sanitize_attr_value(v) for v in value]
-    if isinstance(value, tuple):
-        return tuple(_sanitize_attr_value(v) for v in value)
-    if isinstance(value, (np.datetime64, np.timedelta64)):
-        if np.isnat(value):
-            return None
-        return value.item() if hasattr(value, "item") else value
-    return value
-
-
-def _sanitize_attrs(obj):
-    """Ensure attributes are serialisable by NetCDF writers."""
-
-    obj.attrs = {k: _sanitize_attr_value(v) for k, v in obj.attrs.items()}
-
-
-def _sanitize_variable(obj):
-    """Sanitize both attributes and encoding for an xarray Variable."""
-
-    _sanitize_attrs(obj)
-
-    if not hasattr(obj, "dtype"):
-        return
-
-    dtype = obj.dtype
-    if dtype is None:
-        return
-
-    if np.issubdtype(dtype, np.datetime64) or np.issubdtype(dtype, np.timedelta64):
-        obj.attrs.pop("_FillValue", None)
-        if hasattr(obj, "encoding"):
-            obj.encoding["_FillValue"] = None
-
-
 def wgrib2_idx(grib2filepath: Union[Path, str]) -> str:
     """
     Produce the GRIB2 inventory index with wgrib2.

tests/test_hrdps.py

@@ -81,23 +81,4 @@ def test_hrdps_xarray():
     )
     H.xarray(remove_grib=False)
     assert H.get_localFilePath().exists()
-    H.get_localFilePath().unlink()
-
-
-def test_hrdps_to_netcdf():
-    """Check that a xarray Dataset can be written to a NetCDF file.
-
-    It is important that I have haven't put any python objects in the
-    xarray Dataset attributes.
-    """
-    H = Herbie(
-        latest,
-        model="hrdps",
-        product="continental/2.5km",
-        variable="TMP",
-        level="AGL-2m",
-        overwrite=True,
-        save_dir=save_dir,
-    )
-    ds = H.xarray(remove_grib=False)
-    ds.to_netcdf(save_dir / "test_hrdps_to_netcdf.nc")
+    H.get_localFilePath().unlink()