Updates for Zarr 3 Dtypes (#10456)

Co-authored-by: Deepak Cherian <[email protected]>

Author: ianhi

xarray/tests/__init__.py

@@ -130,6 +130,20 @@ def _importorskip(
 has_rasterio, requires_rasterio = _importorskip("rasterio")
 has_zarr, requires_zarr = _importorskip("zarr")
 has_zarr_v3, requires_zarr_v3 = _importorskip("zarr", "3.0.0")
+has_zarr_v3_dtypes, requires_zarr_v3_dtypes = _importorskip("zarr", "3.1.0")
+if has_zarr_v3:
+    import zarr
+
+    # manual update by checking attrs for now
+    # TODO: use version specifier
+    # installing from git main is giving me a lower version than the
+    # most recently released zarr
+    has_zarr_v3_dtypes = hasattr(zarr.core, "dtype")
+
+    requires_zarr_v3_dtypes = pytest.mark.skipif(
+        not has_zarr_v3_dtypes, reason="requires zarr>3.1.0"
+    )
+
 has_fsspec, requires_fsspec = _importorskip("fsspec")
 has_iris, requires_iris = _importorskip("iris")
 has_numbagg, requires_numbagg = _importorskip("numbagg")

xarray/tests/test_backends.py

@@ -73,6 +73,7 @@
     has_scipy,
     has_zarr,
     has_zarr_v3,
+    has_zarr_v3_dtypes,
     mock,
     network,
     requires_cftime,
@@ -2437,7 +2438,7 @@ def test_read_non_consolidated_warning(self) -> None:
     def test_non_existent_store(self) -> None:
         with pytest.raises(
             FileNotFoundError,
-            match="(No such file or directory|Unable to find group|No group found)",
+            match="(No such file or directory|Unable to find group|No group found in store)",
         ):
             xr.open_zarr(f"{uuid.uuid4()}")
 
@@ -2519,6 +2520,7 @@ def test_manual_chunk(self) -> None:
                 assert_identical(actual.load(), auto.load())
 
     @requires_dask
+    @pytest.mark.filterwarnings("ignore:.*does not have a Zarr V3 specification.*")
     def test_warning_on_bad_chunks(self) -> None:
         original = create_test_data().chunk({"dim1": 4, "dim2": 3, "dim3": 3})
 
@@ -2927,7 +2929,9 @@ def test_append_with_existing_encoding_raises(self) -> None:
 
     @pytest.mark.parametrize("dtype", ["U", "S"])
     def test_append_string_length_mismatch_raises(self, dtype) -> None:
-        skip_if_zarr_format_3("This actually works fine with Zarr format 3")
+        if has_zarr_v3 and not has_zarr_v3_dtypes:
+            skip_if_zarr_format_3("This actually works fine with Zarr format 3")
+
         ds, ds_to_append = create_append_string_length_mismatch_test_data(dtype)
         with self.create_zarr_target() as store_target:
             ds.to_zarr(store_target, mode="w", **self.version_kwargs)
@@ -2940,8 +2944,12 @@ def test_append_string_length_mismatch_raises(self, dtype) -> None:
     def test_append_string_length_mismatch_works(self, dtype) -> None:
         skip_if_zarr_format_2("This doesn't work with Zarr format 2")
         # ...but it probably would if we used object dtype
+        if has_zarr_v3_dtypes:
+            pytest.skip("This works on pre ZDtype Zarr-Python, but fails after.")
+
         ds, ds_to_append = create_append_string_length_mismatch_test_data(dtype)
         expected = xr.concat([ds, ds_to_append], dim="time")
+
         with self.create_zarr_target() as store_target:
             ds.to_zarr(store_target, mode="w", **self.version_kwargs)
             ds_to_append.to_zarr(store_target, append_dim="time", **self.version_kwargs)