def test_invalid_scalar_index(adata, index):
    # https://github.com/theislab/anndata/issues/619
    with pytest.raises(IndexError, match=r".*index.* out of range\."):
        _ = adata[index]
def test_unions(self):
        for code, tp in self.formats.items():
            class X(Union):
                _fields_ = [("x", c_char),
                            ("y", tp)]
            self.assertEqual((sizeof(X), code),
                                 (calcsize("%c" % (code)), code))