Linting

virtualizarr/accessor.py

@@ -1,10 +1,5 @@
 from pathlib import Path
-from typing import (
-    TYPE_CHECKING,
-    Callable,
-    Literal,
-    overload,
-)
+from typing import TYPE_CHECKING, Callable, Literal, Optional, overload
 
 from xarray import Dataset, register_dataset_accessor
 
@@ -43,7 +38,9 @@ def to_zarr(self, storepath: str) -> None:
         """
         dataset_to_zarr(self.ds, storepath)
 
-    def to_icechunk(self, store: "IcechunkStore") -> None:
+    def to_icechunk(
+        self, store: "IcechunkStore", append_dim: Optional[str] = None
+    ) -> None:
         """
         Write an xarray dataset to an Icechunk store.
 
@@ -55,7 +52,7 @@ def to_icechunk(self, store: "IcechunkStore") -> None:
         """
         from virtualizarr.writers.icechunk import dataset_to_icechunk
 
-        dataset_to_icechunk(self.ds, store)
+        dataset_to_icechunk(self.ds, store, append_dim=append_dim)
 
     @overload
     def to_kerchunk(

virtualizarr/tests/test_writers/test_icechunk_append.py

@@ -0,0 +1,80 @@
+from typing import TYPE_CHECKING
+
+import pytest
+
+pytest.importorskip("icechunk")
+
+import numpy as np
+import numpy.testing as npt
+from xarray import Dataset, open_dataset
+from xarray.core.variable import Variable
+from zarr import group  # type: ignore[import-untyped]
+
+from virtualizarr.manifests import ChunkManifest, ManifestArray
+from virtualizarr.writers.icechunk import dataset_to_icechunk
+from virtualizarr.zarr import ZArray
+
+if TYPE_CHECKING:
+    from icechunk import StorageConfig  # type: ignore[import-not-found]
+
+
+@pytest.fixture(scope="function")
+def icechunk_storage(tmpdir) -> "StorageConfig":
+    from icechunk import StorageConfig
+
+    storage = StorageConfig.filesystem(str(tmpdir))
+
+    # TODO instead yield store then store.close() ??
+    return storage
+
+
+def gen_virtual_dataset(file_uri: str):
+    manifest = ChunkManifest({"0.0": {"path": file_uri, "offset": 6144, "length": 48}})
+    zarray = ZArray(
+        shape=(3, 4),
+        chunks=(3, 4),
+        dtype=np.dtype("int32"),
+        compressor=None,
+        filters=None,
+        fill_value=None,
+    )
+    ma = ManifestArray(
+        chunkmanifest=manifest,
+        zarray=zarray,
+    )
+    foo = Variable(data=ma, dims=["x", "y"])
+    return Dataset(
+        {"foo": foo},
+    )
+
+
+def test_set_single_virtual_ref_without_encoding(
+    icechunk_storage: "StorageConfig", simple_netcdf4: str
+):
+    import xarray as xr
+    from icechunk import IcechunkStore
+
+    # generate virtual dataset
+    vds = gen_virtual_dataset(simple_netcdf4)
+
+    # create the icechunk store and commit the first virtual dataset
+    icechunk_filestore = IcechunkStore.create(storage=icechunk_storage)
+    dataset_to_icechunk(vds, icechunk_filestore)
+    icechunk_filestore.commit(
+        "test commit"
+    )  # need to commit it in order to append to it in the next lines
+
+    # Append the same dataset to the same store
+    icechunk_filestore_append = IcechunkStore.open_existing(
+        storage=icechunk_storage, mode="a"
+    )
+    dataset_to_icechunk(vds, icechunk_filestore_append, append_dim="x")
+
+    root_group = group(store=icechunk_filestore_append)
+    array = root_group["foo"]
+
+    expected_ds = open_dataset(simple_netcdf4)
+    expected_array = xr.concat(
+        [expected_ds["foo"], expected_ds["foo"]], dim="x"
+    ).to_numpy()
+    npt.assert_equal(array, expected_array)