attrs() silently omitted any attribute whose datatype had no AttrValue variant
— including every Python bool, which h5py stores as an enum — plus complex,
compound and reference attributes, and cast unsigned 64-bit arrays to
I64Array so values above i64::MAX came back negative.
- numpy/h5py-style booleans (an enum of exactly FALSE=0 / TRUE=1 over an
integer base) decode as I64 / I64Array of 0/1.
- AttrValue::U64Array keeps unsigned arrays unsigned. Behaviour change: an
unsigned array attribute no longer arrives as I64Array; the netCDF-4 CF
helpers (_FillValue, valid_range) and the Python bindings handle it.
- AttrValue::Raw { datatype, shape, data } carries any other attribute
verbatim (also used when a value fails to decode as its declared type), so
the attribute list is always complete. Decodable with data_read against the
datatype; Python receives {"dtype", "shape", "data"}.
- Both new variants are writable, so attributes round-trip between files.
h5py interop tests cover reading 13 attribute kinds and h5py reading back a
compound and a u64 attribute written by clawhdf5.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
