h5py 3.0+ triggers TestHDF5BasicIO Error

[rmcgibbo]

It looks like clifford has recently been failing to build in nixpkgs because of the following test failure. I looked in the issues here, but didn't see this reported. Here's a link to the log in the nix build system: https://hydra.nixos.org/build/134004734.

I believe that this failure results from bumping h5py from 2.10.0 to the latest release, 3.1.0.

=================================== FAILURES ===================================
_____________________ TestHDF5BasicIO.test_write_and_read ______________________

self = <clifford.test.test_io.TestHDF5BasicIO object at 0x7fffa0dc5580>
tmp_path = PosixPath('/build/pytest-of-nixbld/pytest-0/test_write_and_read0')

    def test_write_and_read(self, tmp_path):
        file_name = str(tmp_path / "test.ga")

        basis_names = np.array(layout.basis_names, dtype=str)

        mv_array = ConformalMVArray([random_point_pair() for i in range(1000)]).value
        write_ga_file(file_name, mv_array, layout.metric, basis_names, compression=True,
                      transpose=False, sparse=False, support=False)

        data_array, metric_2, basis_names_2, support = read_ga_file(file_name)

        np.testing.assert_equal(data_array, mv_array)
        np.testing.assert_equal(layout.metric, metric_2)
>       np.testing.assert_equal(basis_names, basis_names_2)
E       AssertionError: 
E       Arrays are not equal
E       
E       Mismatched elements: 5 / 5 (100%)
E        x: array(['e1', 'e2', 'e3', 'e4', 'e5'], dtype='<U2')
E        y: array([b'e1', b'e2', b'e3', b'e4', b'e5'], dtype=object)

test_io.py:35: AssertionError

https://docs.h5py.org/en/latest/whatsnew/3.0.html

The interface for storing & reading strings has changed - see Strings in HDF5. The new rules are hopefully more consistent, but may well require some changes in coding using h5py.

[eric-wieser]

Duplicate of #387, I think?

[rmcgibbo]

Ah sorry. Closing,