(chore): add test

Author: ilan-gold

tests/test_metadata/test_v2.py

@@ -316,3 +316,16 @@ def test_zstd_checksum() -> None:
         arr.metadata.to_buffer_dict(default_buffer_prototype())[".zarray"].to_bytes()
     )
     assert "checksum" not in metadata["compressor"]
+
+
+def test_structured_dtype_fill_value_serialization(tmp_path):
+    group_path = tmp_path / "test.zarr"
+    root_group = zarr.open_group(group_path, mode="w", zarr_format=2)
+    root_group.create_array(
+        name="structured_headers",
+        shape=(100, 100),
+        chunks=(100, 100),
+        dtype=np.dtype([("foo", "i4"), ("bar", "i4")]),
+    )
+
+    zarr.consolidate_metadata(root_group.store, zarr_format=2)