(fix): handle fill_value

Author: ilan-gold

src/zarr/core/buffer/core.py

@@ -470,7 +470,9 @@ def all_equal(self, other: Any, equal_nan: bool = True) -> bool:
         # every single time we have to write data?
         _data, other = np.broadcast_arrays(self._data, other)
         return np.array_equal(
-            self._data, other, equal_nan=equal_nan if self._data.dtype.kind not in "USTO" else False
+            self._data,
+            other,
+            equal_nan=equal_nan if self._data.dtype.kind not in "USTOV" else False,
         )
 
     def fill(self, value: Any) -> None:

tests/test_v2.py

@@ -245,10 +245,16 @@ def test_default_filters_and_compressor(dtype_expected: Any) -> None:
             assert arr.metadata.filters[0].codec_id == expected_filter
 
 
-def test_structured_dtype() -> None:
+@pytest.mark.parametrize("fill_value", [None, (b"", 0, 0.0)], ids=["no_fill", "fill"])
+def test_structured_dtype(fill_value, tmp_path) -> None:
     a = np.array(
         [(b"aaa", 1, 4.2), (b"bbb", 2, 8.4), (b"ccc", 3, 12.6)],
         dtype=[("foo", "S3"), ("bar", "i4"), ("baz", "f8")],
     )
-    za = zarr.array(a, chunks=2, fill_value=None, zarr_format=2)
+    za = zarr.create(
+        shape=(3,), path=tmp_path, chunks=(2,), fill_value=fill_value, zarr_format=2, dtype=a.dtype
+    )
+    if fill_value is not None:
+        assert (np.array([fill_value] * a.shape[0], dtype=a.dtype) == za[:]).all()
+    za[...] = a
     assert (a == za[:]).all()