PanicException derives from BaseException, so `except Exception` let a
library bug through. Every call from the bindings into the library now
runs under catch_unwind and a panic becomes InternalError (RuntimeError)
naming the object. Tests: a hidden hook panics inside the guard; and the
v4 chunk indexes are compared with h5py from Python — with the library
fix reverted, ds[0:30] of the implicit-index dataset now raises
InternalError instead of aborting the test run.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
ds[key] read the whole dataset and sliced it in numpy, and knew six
dtypes. Keys (ints, positive-step slices, Ellipsis, one increasing index
list, compound field names) now map onto hyperslab selections, and the
facade's read_selection bytes become the numpy buffer without a copy
(PyArray::from_vec viewed as the dtype). dtype mapping follows h5py for
all integer/IEEE float widths and byte orders, bool, enum, complex, fixed
and variable-length strings, vlen sequences, opaque, array types and
(nested, padded) compounds; anything it cannot describe exactly is a
TypeError. Attributes return what h5py returns; groups and files gain
the rest of the h5py mapping interface. Reads run under py.detach.
tests/test_read_vs_h5py.py compares >500 reads with h5py 3.16 on an
h5py-written file, checks errors match, that a damaged chunk outside the
selection is never touched, and 8 threads reading at once.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
