Fix comparison of strings in HDF5 files

tests/test_reference_runs/test_pre_deployment.py

@@ -89,15 +89,19 @@ def validate_file(
             elif out_ds.dtype != ref_ds.dtype:
                 changed.append((dsname, f"Dtype: {ref_ds.dtype} -> {out_ds.dtype}")) # noqa
             else:
-                nanable = np.issubdtype(ref_ds.dtype, np.floating) \
-                          or np.issubdtype(ref_ds.dtype, np.complexfloating)
+                floaty = np.issubdtype(ref_ds.dtype, np.floating) \
+                        or np.issubdtype(ref_ds.dtype, np.complexfloating)
 
                 # Compare data incrementally rather than loading it all at once;
                 # read in blocks of ~64 MB (arbitrary limit) along first axis.
                 for chunk_slice in iter_sized_chunks(ref_ds, 64 * 1024 * 1024):
                     ref_chunk = ref_ds[chunk_slice]
                     out_chunk = out_ds[chunk_slice]
-                    if not np.allclose(ref_chunk, out_chunk, equal_nan=nanable):  # noqa
+                    if floaty:
+                        eq = np.allclose(ref_chunk, out_chunk, equal_nan=True)
+                    else:
+                        eq = np.array_equal(ref_chunk, out_chunk)
+                    if not eq:
                         # If just 1 entry, show the values
                         if ref_ds.size == 1:
                             r, o = np.squeeze(ref_chunk), np.squeeze(out_chunk)